Primary Science 5 Student Book PDF

PRIMARY
SCIENCE
5
Student
Book
P U B L I S H I N G
GLOBAL EDUCATION
Juxon House, 100 St. Paul’s Churchyard EC4M 8BU, London, UK
www.globalbridgepublishing.com | info@globalbridgepublishing.com
P U B L I S H I N G
Global Bridge Publishing is a part of Global Education.

© Global Bridge Publishing 2017
All Rights Reserved. No part of this book may be reproduced or utilized

in any form or by any means, electronic or mechanical, including
photocopying, recording, or by any information storage and retrieval
system, without permission in writing from the publisher.
ISBN 978-1-911533-16-0
9 781911 533160
About the Book
The Global Bridge Science Series has been developed for use in Primary Science curriculum. The
subjects in this book have been arranged in a graded approach; moving from simple to complex
(the constructivist approach).
The book is designed to be student friendly so that students enjoy science. The book uses colour
graphs, pictures and tables to make information clear and easy to remember.
Subjects are explained in simple language through clear sentences with carefully drawn
illustrations. There are plenty of examples, activities, multiple-choice questions to improve
students’ understanding in science. The activities are arranged to engage different learning styles
(such as the multiple-intelligence learning style) and encourage student-centered learning.
Multiple-choice tests at the end of each section cover the material in the section. Uses of scientific
concepts in daily life are included together with pictures. In topics related to math, simple numbers
are used to make calculations easier. It is our sincere hope that teachers will find this book useful.
We wish you every success on your journey into the enjoyable world of science.
How To Study Science?

Science is the subject that helps you to learn about the things that are happening around you. To
learn science better, following points can be helpful for you.
1. Science is learned by reading, searching and doing.
2. Read the topics before class.
3. Science topics are usually related to each other, so try to understand each topic before going
to next one.
4. Do not try and memorize every scientific concept. In science, understanding the concepts is
important.
5. Listen to your teacher carefully. Participate in class discussions.
6. Ask your teacher when you do not understand.
7. During laboratory, follow the instructions of your teacher.
8. Read the assigned material after class.
9. Do homework regularly. Homework gives you the opportunity to learn how science works.
10. Participate in science projects.
Contents
Chapter 1 MY BODY
1. Nutrients and a Balanced Diet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2. Digestion of Food . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3. Excretion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4. Substances That Are Harmful to Your Health . . . . . . . . . . . . . . . . . . . . 33
Chapter 2 THE STATES OF MATTER

1. The Effects of Heat on Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
2. The Changing States of Water in Nature . . . . . . . . . . . . . . . . . . . . . . . 52
Chapter 3 FORCE AND MOTION

1. Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
2. Let’s Get To Know Magnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
3. Friction Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Chapter 4 ELECTRICITY IN YOUR LIFE

1. Simple Electric Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Chapter 5 THE EARTH, THE SUN, AND THE MOON
1. Journey Through the Cosmos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2. Motion of the Earth and the Moon. . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Chapter 6 THE WORLD OF LIVING THINGS

1. Classification of Living Things . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
2. The Environment You Live In . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Chapter 7 LIGHT AND SOUND

1. Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
2. Sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
1. Nutrients and a
Balanced Diet
2. Digestion of Food
3. Excretion
4. Substances That Are

Harmful To Health
CHAPTER 1 | MY BODY 7
1. NUTRIENTS AND
A BALANCED DIET
1. Why Do Living Things Need Food? 2. The Contents of Food and Function
of Nutrients
One of the differences between living things
and non-living things is that living things grow and
Nutrients are important substances for living
develop. What factors do you think are connected
things.
to a living thing’s growth? Would a young living
thing grow if it didn’t eat? There may be more than one kind of nutrient in
the foods you eat everyday, at meals and between
Living things must eat to grow. They also need
meals.
energy for their daily activities. Living things get
the energy they need from nutrients.
Living things must eat:

▸ to grow.
▸ for their bodies to be renewed and developed.
▸ to produce the energy they need.
▸ to carry out their bodily functions, such as,
respiration, circulation, and excretion.
Foods can contain more than one kind of nutrient.
Nutrients play important roles in keeping your

body healthy and control the way it grows.
WE MUST EAT TO GROW AND You should eat a wide range of different types
DEVELOP of food, in order to stay healthy. Nutrition is the
science that studies food and how the body uses it.
There are six groups of nutrients: carbohydrates,
proteins, fats, vitamins, water, and minerals.
You must eat to be able to carry out activities like doing

sports and studying.
8 PRIMARY SCIENCE 5 STUDENT BOOK

Carbohydrates
Vitamins Water
Nutrients Your
Body Needs
Soda
Fats Minerals
▶ Proteins Proteins
After water, proteins are the most abundant

substance in your body. The main function of
proteins in the body is to build and repair tissue.
Proteins are also important for mending broken
bones, repairing cuts and bruises and fighting off
disease.
Proteins are found in both animal-based and
plant-based products.
Protein is found in some plants (beans,
chickpeas and lentils) in grains (wheat, rye, barley
and nuts) in animal-based foods (milk, cheese,
egg, fish, and meat).
Animal-based foods containing protein
Plant-based foods containing protein
▶ Carbohydrates
Carbohydrates are the main source

of energy for your body. Carbohydrates
are mostly found in foods that come
from plants such as: wheat, rice, corn,
oats, potatoes, and sugar cane. Your
body obtains carbohydrates when you
eat foods such as: macaroni, breakfast
cereals, corn, rice, bread, beans, and
potatoes. Carbohydrates are quickly
and easily turned into energy in your
body.
Foods containing carbohydrates
Carbohydrates in Food
You need: Lugol’s solution (ask your teacher to supply this), an eye dropper, various foods – bread, rice,
corn, potato chips, potatoes, apple, butter, peanuts, milk, cheese, starch.
Lugol’s solution
Preparation:
1. Take a small amount of each food and place it on a tray.
2. Place one or two drops of Lugol’s solution onto each food. If the food contains carbohydrate, it will
turn blue or purple.
3. Which foods in your experiment contain carbohydrate? What did you observe?
...................................................................................................
...................................................................................................
Careful: Don’t eat the foods that you dropped Lugol’s solution onto.

▶ Fats
Fats act as a fuel, to provide the energy

necessary for your body. If you Don’t have
enough carbohydrates, fats are used as
secondary sources of energy in your body.
You need fat for your body to grow and
develop.
Fats can be found in both animal-based
and plant-based foods. A great quantity of oil
(fat) is found in the seeds and fruits of plants
such as: sunflowers, corn, olives, peanuts,
sesame nuts, almonds, walnuts, hazelnuts,
and pumpkins seeds.
Animal-based foods that are rich in fat
include: meat, fish, milk, cheese, and butter.
Fats in Food
You need: Paper, pen/pencil, toothpicks, various foods – potato chips, potatoes, apple, butter, peanut,
cheese.
Preparation:
1. Draw a circle on the paper for each type of food. Write the name of each type of food under the
circle. Take a small amount of each food and drop or squash it into its labelled circle.
2. Wait five to ten minutes for it to dry. Hold the paper up to the light. If the food is fatty, the paper will
be translucent to light.
3. Which types of food in your experiment contain fat?
...................................................................................................
...................................................................................................
▶ Vitamins Some vitamins can be stored in the body, but
some cannot. This means you need to get enough
Your body needs vitamins to work properly. vitamins regularly, every day.
They control/regulate functions in the body. They
also make the body strong to protect it against
diseases. Fruits and vegetables are rich in vitamins.
Like all foods, vitamins also have a role in growth
and development. VITAMIN THEIR FUNCTION
There are six main types of vitamins found
in your body. The table below shows these six
vitamins, as well as some of the foods that are rich
This vitamin plays a very important
in these vitamins.
role in eyesight especially at night.
A
In addition, it helps your body fight
infections.
These vitamins are a group. They are

Fruits and vegetables are some of the foods you need important in metabolic activity. They
to eat to get enough vitamins. B also have an important role in making
blood. They help the heart, muscles
VITAMIN FOUND IN THESE FOODS
and other body parts work well.
Liver, milk, eggs, wheat, green beans,

A tomatoes, carrots, walnuts, and This vitamin is important for healthy
pistachios. muscles, bones, joints, teeth, and
gums. It helps your body heal, after
C
you are wounded.
Grains, milk, yogurt, cheese, eggs, This vitamin also increases your
B
meat, and vegetables body’s resistance to infection.
Oranges, lemons, tangerines,
tomatoes, strawberries, cabbage,
C celery, potatoes, rose hips,
blackberries, and dark green leafy This vitamin strengthens bones and
D
vegetables teeth. All bones need vitamin D.
Liver, milk, cheese, eggs, fish, fish oil,

D
butter, and vegetables
This vitamin protects your body or-
E gans from damage and is important
for healthy blood.
Grains, eggs, milk, cheese, yogurt,
E
meat, and vegetables
This vitamin is important for healthy
Liver, meat, green vegetables, blood. When your body is wounded,
K
K rice, corn, tomatoes, strawberries, this vitamin helps to stop the bleed-
peaches, and bananas ing.

▶ Water 3. Balanced and Healthy Nutrition
Water is an important Your body needs all the nutrients for growth,
substance for animal development, repair, regulation, and energy. This
and plant life. All living means you should eat enough of a variety of foods
things need water to at every meal. Eating enough of the foods that your
survive. The human body needs at the correct time interval is called
body consists of 70% balanced nutrition.
water. Your body has
many functions and
needs water to carry out
many of them. Without Water is necessary for
water, your body would the continuation of living
stop working properly. things’ bodily functions.
For example, your blood
contains water, and it carries oxygen to the organs
of your body. If there is no oxygen, your organs
would not be able to produce energy and they
would die. In a balanced diet, more carbohydrates, proteins,
and fats should be eaten than vitamins and
You get the water you need by drinking it. In minerals. You should drink an average of 8 cups
addition, you also get some water from the food
of water a day. This should be increased when the
you eat. There is a lot of water in fresh fruits and
weather is hot and when you are doing sports.
vegetables, especially in melons and watermelons.
If you don’t get enough nutrients, you will
▶ Minerals become sick and unhealthy more often. A healthy
diet means, not just eating the right foods, but also
Minerals regulate your body functions. You get avoiding unhealthy foods. Foods with artificial
minerals from the food you eat and drink: water, colours and carbonated soft drinks can damage
mineral water, fruit juice, vegetables, and fruits. our health. Eating a lot of fast food like hamburgers,
When you Don’t get enough minerals, you will have pizza, and chips is a bad eating habit. You should
problems with your health. For example, if you don’t take care not to eat too much of these kinds of
have enough minerals your bones will weaken. foods.
Minerals let you grow, develop, and stay healthy!
Examine the table of nutrients and their functions
4. Food and Technology
given below.
Technological developments have increased the
variety of foods and drinks available to humans.
New fruit juices, breakfast cereals, milk products,
Primary function Nutrient
candies, chocolates, mayonnaise, sauces, and
Carbohydrate frozen foods are some of the foods that are
Energy supply available because of technological developments.
Fat When you use these kinds of foods, pay attention
to the expiration date and whether it was made by
Growth and repair Protein a trusted company. If so, and the food makes you
sick, you should be able to easily complain. This
will make them more careful. You should also read
Vitamins
the contents information, printed on the package.
Regulation Water
Minerals You should buy fresh fruit and vegetables, and
only eat fruit and vegetables which are in season.
1
WHY DO LIVING THINGS EAT?
A B C D
E F G H
Soda
I J K L
Answer the questions below about the pictures above.
1. Which are plant-based foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2. Which are animal-based foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. Which come from neither an animal nor a plant source? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. Which are produced from wheat? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5. Which are produced from meat? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6. Which are produced from milk? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7. Which come from the sea? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8. Which are fruits? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9. Which are dried foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2
THE CONTENTS OF FOOD AND FUNCTIONS OF NUTRIENTS
Write down the types of nutrients present in each picture below.
1 2 3
.......................... .......................... ..........................
4 5 6
.......................... .......................... ..........................
7 8 9
.......................... .......................... ..........................
3
THE CONTENTS OF FOOD AND FUNCTION OF NUTRIENTS
Fatima is studying her science homework. Her father is helping her. Fatima is making a concept map to
show different kinds of foods and their use/function. Help Fatima by completing the map below.
Providing Energy Regulating in

Prote
Vitamins
s Fat Minerals
Carbohydrate

4
Living things must eat. Complete the sentences below to explain the reasons why living things eat, one
sentence is given as an example.
Living things eat ...
1. .... to get the energy they need to run.
2. .... to ____________________________________________________________________________________________.
3. .... to ____________________________________________________________________________________________.
4. .... to ____________________________________________________________________________________________.
5. .... to ____________________________________________________________________________________________.
6. .... to ____________________________________________________________________________________________.
5
Write a “T” for true/correct sentences and an “F” for false/incorrect sentences.
1. [......] Very small living things don’t need to eat.
2. [......] You get nutrients from food.
3. [......] Living things don’t use energy when they are asleep.
4. [......] All foods have the same taste.
5. [......] Energy is not found in vitamins and minerals.
6. [......] Milk is a plant-based food.
7. [......] Living things can’t live if they can’t eat.
1
1. A mother is encouraging her children to eat 5. In the table below, various foods are grouped
natural foods. according to whether they are plant products
or animal products.
Which food do you think this mother is not
Which pair is incorrectly matched?
encouraging them to eat? CCC
Plant products Animal products
A) Tomatoes B) Water
A) Vegetables Milk
C) Chocolate D) Honey
B) Fruit Meat
C) Honey Pickles
D) Sunflower seed oil Eggs
2. I. Water
II. Vitamins
III. Minerals
What do the substances above have in
common?
A) They provide energy for the body.

6. Nutrients that have a role in the functions and
B) They are found in large amounts in all
activities of body organs are called regulatory
foods.
nutrients.
C) They are only important for the development
In which of the following pairs, are nutrients
of bones and teeth.
with a regulatory function shown together?
D) They have a regulatory function in the body. DDD
A) Carbohydrates - Fats
B) Proteins - Fats
C) Carbohydrates - Proteins
3. Which of the foods below has more fat than D) Vitamins - Minerals
the others?
A) Hazelnut B) Apple
C) Melon D) Bread
4. Which of the following are things you should 7. I. It is the most common nutrient found in
avoid to keep a balanced meal? your body.
DDD II. It is in the regulatory nutrients group.
A) Eating a lot of fatty foods and foods made
from flour. Some information is given above about a
certain nutrient.
B) Eating foods that are high in energy.
Which of the following is this nutrient?
C) Eating only a little. AAA
A) Water B) Carbohydrate
D) Eating enough of the foods that your body
needs. C) Minerals D) Proteins

2. DIGESTION OF FOOD
1. Transportation of Nutrients ▶ How Does Digestion Happen?
What happens to food after you eat it? Let’s look Digestion begins when food is taken into the
at your daily activities. You walk to school, play mouth. It finishes when waste is expelled from the
sports and study. You use energy to do all of these anus. The activities that happen between these
things. Energy is necessary for breathing and for two events digest the food. The activities that
your heart to pump blood, as long as you are alive. make food digestion possible can be summarised:
Energy is produced in
every part of your body.
You need oxygen and
nutrients to produce
energy.
Nutrients and oxygen
are transported through
your body by your blood.
Mouth
After food is taken into
your body, it is broken
down into very small Gullet
pieces in the digestive
organs, so that it can
pass into your blood.
This process is called You use energy to carry out
digestion. your daily activities.
Digestion takes place in the digestive organs
and structures. The digestive organs form a canal Stomach
that starts at the mouth and ends at the anus.
This canal is called the alimentary canal or the
digestive tract. Organs that digest your food are Large
found in the digestive tract. There are other organs Small Intestine
Intestine
that also help with digestion.
On the next page, the functions of the digestive
organs and structures are explained. Carefully
examine the shape and function of these organs
and structures.
Broken down Digestive organs
food
digestion
process
Food
od
Blo
In the Mouth:
MODEL OF DIGESTIVE ORGANS
Digestion begins as food is taken into the mouth.
The food taken into the mouth is crushed and cut
into small pieces by the teeth. As the food is being
chewed in the mouth, it is mixed with saliva. Saliva
makes food moist, soft and slippery, which makes
it easier to swallow. mouth
In the Gullet (Food Pipe): Gullet

Food in the mouth is pushed towards the gullet
(Food pipe)
by the tongue. As the gullet slowly contracts, the
food moves to the stomach. liquids
stomach
In the Stomach:
The stomach muscles contract and slosh, mix
small
and squeeze the food. Some liquids are produced
liquids intestine
in the stomach, and these liquids separate the food
into much smaller pieces. The food then passes
from the stomach into the small intestine, in the
form of a soup.
In the Small Intestine:

The food is mixed with different liquids in
large
the small intestine. These liquids completely
breakdown the food into very small pieces. In this intestine
way the nutrients are changed into a form in which
they can pass into the blood. As the food moves anus
along, the nutrients pass into the blood from the
small intestine. faeces
In the Large Intestine:

The helpful nutrients are absorbed from the food
in the small intestine, leaving a waste pulp behind.
This waste pulp passes into the large intestine.
Water and minerals are absorbed from this pulp The digestive organs digest the food by working like a
in the large intestine. This pulp, called faeces, is machine.
expelled from the body at the anus and digestion
is complete.

DIGESTIVE ORGANS
The organs that take place in the digestion of food.
1
MOUTH
Teeth, the tongue, and the
structures that make saliva are
found in the mouth.
GULLET
(FOOD PIPE)
The gullet is
a long tube
from the
mouth to the
stomach.
STOMACH
In the stomach, the food is
broken down into smaller
pieces.
It is the largest digestive
organ and is situated below 2
the chest.
SMALL INTESTINE
LARGE INTESTINE The small intestine is a long
The large intestine is a tube. folded-up tube structure.
It looks similar to the small
intestine, but shorter. The
opening at the end is called the
anus.
anus 5
6
DIGESTIVE ORGANS AND STRUCTURES
Write down the name of the organ under each picture. Match the digestive organs with the question
marks inside the body.
............................................ ............................................
?
............................................ ?
............................................
............................................

7
TRANSPORTATION OF NUTRIENTS
Complete the sentences by using the best word from the list below.
nutrients blood tongue digestion
saliva energy heart mouth
1. We use ................ to perform our daily activities. 5. The ............... is the beginning of the digestion
system.
2. ........................ is the term for breaking down
food into small enough particles, that the 6. When food is mixed with .......................... it is
nutrients can pass into the blood. moistened and made slippery.
3. Oxygen and ........................ are necessary to 7. Food is pushed towards the gullet by the
produce energy. ......................... .
4. After being digested, nutrients pass into the 8. The .................. is not a digestive organ.
.............. .
8
DIGESTIVE ORGANS AND FUNCTIONS
The scrambled words listed below are related to digestion. Unscramble them and write them in the
rows shown by the arrows.
ALLSM TESINNETI
MACHSTO
GESDITION
OTHTO
GELAR TINEINTES
TUGLLE
THMOU
AUNS
2. Our Teeth and Their Functions
Hard, solid foods need to be broken down into Permanent teeth begin to grow after milk teeth
Zambak Publishing
small pieces by the teeth, so that they can be have fallen out, at about age 7 or 8. The following
swallowed and digested easily. However, tearing, are the four kinds of teeth:
breaking, and crushing food into tiny pieces can’t 1. Incisor
all be done by just one kind of tooth. Our teeth
2. Canine teeth
look different from one another and have different
functions. There are four kinds of teeth which can 3. Molars
be grouped according to their shape and function. 4. Wisdom teeth
Incisors Molars
These are the sharp The large teeth at the back
teeth at the front of of the mouth. Molars’ wide
the mouth. They are chewing surface make it
good for biting and easy to crush and grind
tearing food. food on them.
Canine Teeth Wisdom Teeth

These are pointed These are shaped like the
teeth, they are good molars. They come through
for ripping and tearing the gum between the ages of
food. 18 and 22.

3. Dental Health and Care ▶ How Should You Brush Your Teeth?
The health of the mouth and teeth are important First, choose a soft to medium toothbrush. Look
for your health. This is because the teeth and at the pictures below, follow the steps that show
mouth are related to the other digestive organs. If you how to brush your teeth.
you do not take care of your teeth, they will decay.
▸ Move the brush in an upward and downward
Tooth decay can be caused by direction.
▸ food left between the teeth, especially sugary ▸ Make small circular motions.
foods. ▸ Brush the inner surfaces of teeth in the same
▸ food or drink that is too acidic. way.
▸ foods that are excessively hot or cold.
▸ using teeth to break down the shells of hard
foods, like hazelnuts and walnuts.
▸ placing sharp items in the mouth.
Healthy teeth Unhealthy teeth
There are several diseases that can result from

not taking care of your mouth and teeth.
These are some of the rules that help to prevent
these diseases, and protect against oral and dental
health.
▸ Sufficient minerals and vitamins A, C and
D should be taken, especially during your
childhood.
▸ Your teeth should not be used to break down
hard-shelled food.
▸ Too much sugary and acidic foods should be
avoided.
▸ Foods like apples and carrots should be eaten
by biting them.
▸ You should see the dentist at least twice a year.
▸ Your teeth should be properly brushed every
morning before breakfast and every evening
before going to bed.
9
YOUR TEETH AND THEIR FUNCTIONS
Some characteristics of teeth are given below. Use arrows to match the characteristics to the box, for
the appropriate kind of tooth. Draw a picture of the kind of tooth described by the frame.
h
Incisors Canine Teet
ripping food
Useful for
biting and
tearing food.
Have a wide
surface Grind
food
Break food
into small
pieces Pointed teeth
Molars th
Wisdom tee
Grow between
the ages of 18
and 22.

10
DENTAL HEALTH AND CARE
The pictures below show the proper way to brush your teeth. Under the pictures, write down three
pieces of advice about brushing teeth and choosing a toothbrush.
After eating food, enamel on the ___________________________________ ___________________________________

outside of your teeth softens. ___________________________________ ___________________________________
If you brush you teeth when the ___________________________________ ___________________________________
enamel is soft you will damage ___________________________________ ___________________________________
them. After eating, wait for about ___________________________________ ___________________________________
an hour before brushing your teeth. ___________________________________ ___________________________________
11
DENTAL HEALTH AND CARE
In the boxes below, write down three causes of tooth decay and three ways to prevent tooth decay.
CAUSES OF PROTECTION FROM

TOOTH DECAY: TOOTH DECAY:
.................................................... ....................................................
.................................................... ....................................................
.................................................... ....................................................
.................................................... ....................................................
2
1. Which of the following does not have a role in 4. Which of the following information about the
breaking down food into small pieces to pass functions of the incisors and the canine teeth
into the blood? is correct?
AAA BBB
A) Large intestine B) Mouth Canine teeth Incisors
C) Stomach D) Small intestine A) Tear Crush
B) good for ripping food biting and tearing
food
C) Crush Break through
D) Break into Crush
small pieces
2. Imagine you are a dentist.
Which of the advice below, about dental
health, should you not give to a patient?
A) Foods with a shell shouldn’t be broken

with the teeth. 5. Digestive organs and structures are matched
B) Teeth should be brushed regularly, twice a with their functions below.
day. Which matching function is incorrect?
C) Very hot or very cold food shouldn’t be CCC
eaten. A) Mouth → The first place where food is broken
down.
D) If your teeth look alright, you shouldn’t go
to the dentist. B) Gullet → Makes it possible for food to pass
from the mouth to the vessels.
C) Small intestine → The place where digested
food passes into the blood.
D) Large intestine → Makes it possible for
waste matter to be expelled from the anus.
3. Which of the following about molars is 6. I. Very hot and very cold food shouldn’t be
incorrect? eaten.
CCC
II. The foods you eat should be fresh.
A) They grow after age 30.
III. Food should be well chewed.
B) They have wide chewing surface.
Which of the above should you do to protect
C) They have a role in breaking up and crushing the health of your digestive organs?
food. DDD
A) I and II B) II and III
D) An adult has a total of 8, four in the upper
jaw and four in the lower jaw. C) I and III D) I, II and III

2
7. 10.
Mouth I
Gullet II
Large intestine III
A part of the small intestine is shown in the

picture above.
Small intestine IV
Which of the following information about this
Look at the picture above. organ is incorrect?
From which numbered organ do nutrients DDD
pass into the blood? A) Digested nutrients are absorbed here.
B) Its a digestive organ.
A) I B) II C) III D) IV
C) Its a structure in the shape of a long, thin
tube.
D) No digestive activity occurs in this organ.
8. Which organ is not a part of digestive system?
A) Heart B) Stomach
C) Large Intestine D) Small intestine 11. What is the name of the event in which food is
broken down and passes into the blood?
DDD
A) Breathing B) Excretion
C) Circulation D) Digestion
9. Which of the following is the function of the

molars in the digestion of food?
A) Crushing food.
12. How many kinds of teeth, according to their
B) Ripping food. shape and function, are there in the mouth of
C) Cutting food. a healthy adult?
D) Mixing food. A) 5 B) 4 C) 3 D) 2
3. EXCRETION
1. Excretory Organs and Structures

Do you know what function kidneys have in your body? Waste materials
are produced by the body’s activities. The process of removing the waste
products from the body is called excretion. There are four organs and
structures in your body that are responsible for removing waste products.
Excretion is made possible by the kidneys, ureters, urinary bladder, and
urethra.
1
2
URETER
A tube that
carries urine
KIDNEYS from the kidney
Humans normally have to the bladder.
two kidneys. The kidneys
are shaped like beans.
They are located to the
right and left of the spine
at waist level. The kidneys
remove waste matter from
the blood by filtering it. 3
BLADDER
URETHRA The bladder is an organ that is
This is a short tube shaped like a bag, here urine is
which carries urine collected and stored for a time.
from the bladder out
of the body.
4

▶ The Health of Your Kidneys
The kidneys are among the most important

organs in your body. If the kidneys Don’t carry out
their function properly, harmful waste will build-up
throughout your body , placing your life in danger.
This means you must take care of your kidneys.
Taking care of your kidneys:
▸ You should drink a lot of fresh water, especially
in hot weather when you lose a lot of water by
sweating.
▸ Don’t eat very salty or spicy foods.
▸ Don’t let your body get too cold, especially
around the waist. Clothes that leave the waist
uncovered can be harmful for the health of your
kidneys.
▸ Keep your body clean, wear clean clothes, and
bathe frequently.
▸ Your hands should be washed with hot water
and soap after using the toilet.
▸ Pain or burning during urination should not be
ignored. See a doctor if you experience these
symptoms.
Take care to protect the health of your kidneys,

you only have one pair.
12
EXCRETION
Write down the name of the organs and structures shown under each picture.
13
EXCRETION
1. The harmful gas that is expelled when you exhale.

2. Waste material expelled through the skin.
3. The structure through which digestive waste is
expelled.
4. Organ that cleans your blood by filtering out
harmful substances.
5. Waste material filtered from your blood by your
kidneys.
6. The activity of expelling from your body the waste
filtered out of your blood.
7. The liquid that you need to drink a lot of to keep
your kidneys healthy.
8. Excretory organ where urine is stored for a time.
9. The tube through which urine is expelled.
10. The tube that transports urine from your kidneys
to your urinary bladder.

4. SUBSTANCES THAT ARE
HARMFUL TO YOUR HEALTH
1. The Harm Done by Cigarettes and Alcohol Look at the pictures below. Which pair of lungs
is healthy? Which pair do you want to have?
People have been using harmful substances for
many centuries. However, if a person starts using
these harmful substances they become habits;
this means that the brain starts to think it needs
these substances. However, over time, they cause
terrible health problems.
Harmful substances affect the health of the
body negatively. Today, the most widely used A smoker’s lungs A non-smoker’s lungs
harmful substances are cigarettes and alcohol.
“Passive smokers” are the name given to people
who don’t smoke, but who are affected by the
smoke from people smoking around them. Passive
▶ The Harm Done by Cigarettes
smokers are affected by cigarettes in the same
Cigarettes are the most common harmful habit way that smokers are. Passive smoking is most
in the world. damaging for babies and children. It will cause
long term health problems into their adult life.
There are more than four thousand (4000)
harmful substances in cigarettes. These substances
harm cigarette smokers. Most of this harm is done
in the respiratory organs. However, the whole body
is affected by the poisons found in cigarettes,
because they are transported around the body
through the blood. Even carbon monoxide, the
gas that comes out of car exhausts, is found in Cigarette smoking
cigarettes. can destroy your
lungs, preventing you
breathing by yourself.
A list of the damage that cigarettes cause: You also spoil the
air for people around
▸ Cigarettes are the source of 90% of lung you.
cancers and cancer of the larynx.

Cigarettes do great harm to the environment.
▸ Cigarettes are one of the main causes of
heart disease and circulatory problems. Cigarettes pollute
clean air for people
in your community.
▸ Cigarettes are the cause of some stomach If accidentally
illnesses and digestive problems. dropped, they cause
environmental
disasters, like fires.
▸ If pregnant women smoke it can cause birth
defects and low birth weight.
▶ The Harm of Alcohol
Just like cigarettes, it has Decide whether the following statements are true
been proven by scientific (T) or false (F).
studies that alcohol has many
harmful effects. Alcohol 1) There are about four thousand harmful
increases people’s problems. substances in cigarettes.
2) Alcohol does a lot of damage to society and
families, as well as individuals.
3) Cigarette smoking is the most widespread
harmful habit.
A list of some diseases caused by alcohol; 4) Its easy to give up drinking alcohol and
smoking.
▸ It reduces a person’s ability to think for
many hours. This may cause them to harm
themselves or others.
▸ It badly affects a person’s ability to control
their own body. This may cause them to harm
themselves or others.
▸ It is the main cause of cirrhosis of the liver.
▸ It damages the brain.
▸ It causes digestive problems. It leads to
gastritis and intestinal illnesses. The liver of someone with cirrhosis.
▸ It prevents some vitamins being absorbed by
the body. The senses of sight, hearing, and
touch are weakened.
▸ It increases blood pressure.
▸ It damages the kidneys.
▸ It is the reason for blood diseases.
A healthy person’s liver.
Drunk driving is one of the biggest causes of Cigarettes kill your lungs.
traffic accidents.

14
MY BODY
Some of the characteristics of substances that are harmful to health are given below. Identify which
characteristics belong to alcohol, and which to cigarettes by writing “Alcohol” or “Cigarettes” in the space
at the beginning of the sentences.
1. [........... ........] It increases the risk of lung and laryngeal cancer many times over.
2. [........... ........] Passive smokers are the non-smokers near a smoker, who are forced to breathe the
smoke coming from the smoker’s lungs.
3. [........... ........] These people have problems with balance and with judging how to drive correctly.
4. [........... ........] It is one of the main causes of forest fires.
5. [........... ........] It is the most common harmful habit in the world.
6. [........... ........] Its smoke and ash dropped in the environment pollute the air.
7. [........... ........] It damages the kidneys, causing cirrhosis.
8. [........... ........] It contains poisonous gases, like carbon monoxide.
15
THE HARM DONE BY ALCOHOL
Below are an alcoholic’s liver and brain. The liver and brain want to explain to their owner the damage
done by drinking alcohol. Write down what they will explain.
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
16
MY BODY
Write down the answers to the questions below in the correct places in the crossword puzzle.
1. All food and drink that goes into your body.
2. The name of the organ into which food goes after leaving the
gullet (food pipe) during digestion.
3. The process in which harmful substances are expelled from
your body.
4. The name of an organ that cleans your blood by filtering out
harmful substances.
5. The break down of food in your body, allowing nutrients to pass into your blood.
6. 90% of lung cancers and 99% of cancers of the gullet originate from this harmful substance.
7. Something your body needs for activities like walking, running, talking, and thinking.

17
MY BODY
Find and circle the given words in the puzzle.
ENERGY VITAMINS
MILK FISH
STOMACH SMALL INTESTINE
KIDNEY NICOTINE
CARBOHYDRATE LARGE INTESTINE
BREAD BLOOD
S M A L L I N T E S T I N E Y NUTRIENT
MINERAL
O I U A H A U V E S O F I S H EGG
MOLAR
E N E R G Y T L F A T V C E K
WATER
D E G G R P R O T E I N O S I BODY
D R T E I M I L K H E R T T D
NUTRITION
I A B I N I E X C R E T I O N
PROTEIN
G L O N D D N D L E O F N M E FAT
EXCRETION
E O D T V I T A M I N S E A Y SPORTS
NATURAL
S U Y E R B O D S U G A R C Y
T W A S T E S I P N C M E H B
DIET
I N U T R I T I O N R O E C L SUGAR
DIGESTION
O O N I N A T U R A L L D G O WASTE
N R A N H E A L T H T A I U O GRIND
HEALTH
W A T E R L A T S I B R E A D
O N C A R B O H Y D R A T E S
1
1. I. Urinary bladder 3. I. Driving while drinking alcohol is a crime.
II. Ureter II. The organs most affected by alcohol are
III. Urethra the liver and the brain.
Which of the excretory organs listed above has Which of the following choices about the
the shape of a pipe? statements on alcohol above are correct?
BBB CCC
A) I only B) II and III A) Only I is true.
C) I and III D) I and II B) Only II is true.
C) They are both true.
D) They are both false.
4. Which of the following organs is not involved

in digestion?
BBB
A) Mouth B) Urethra
C) Small intestine D) Stomach
2.
Organ Function
Lungs Breathing
Stomach I
5. Which of the following is a description of bal-
Kidney II
anced nutrition?
Ureter III DDD
A) Large quantities of carbohydrates are taken
Some organs and their primary functions are into the body to meet the body’s energy
shown in the table above. needs.
Which of the following should go in the spaces B) More food is eaten than the body needs for
I, II and III? its growth, repair, and daily energy require-
BBB ments.
I II III C) Less food is eaten than the body needs for
A) Breathing Digestion Excretion its growth, repair, and daily energy require-
ments.
B) Digestion Excretion Excretion
D) Enough food is taken into the body to meet
C) Excretion Breathing Digestion
daily energy requirements, as well as what is
D) Digestion Excretion Breathing needed for growth and repair.

1. The Effects of Heat on Matter
2. The Changing States of Water in Nature
CHAPTER 2 | THE STATES OF MATTER 39

1. THE EFFECTS OF HEAT
ON MATTER
What Is Heat Transfer?

If you leave a cold teaspoon in a cup of hot
tea and touch it later, you will notice that its
temperature has increased.

This means that when substances of different
temperatures are in contact with each other, they
transfer heat. Hot substances lose heat, cold When a hot piece of iron is in contact with cold water,
substance absorb heat. This goes on until the heat energy is transferred from the hot iron to the cold
water.
substances reach the same temperature.
The ice in the glass absorbs heat from the surroundings

and becomes liquid water.
Heat Transfer
You need: A large and a small beaker, two thermometers, cold water and hot water.
Preparation:
1. Pour the same amounts of cold and hot water into the beakers. Pour the hot water into the small
beaker, and pour the cold water into the large beaker.
2. Place the small beaker into the larger one.
3. Measure the temperatures inside each beaker every minute and record them in the table below.
4. Observe what happens to the temperature of water in each beaker.
Time (min.) 1 2 3 4
Temp. of water in large

beaker (°C)
Temp. of water in small

beaker (°C)

1. Expansion and Contraction If you heat a metal object, its volume will
increase. If you cool it, its volume will decrease.
Does heat effect only the temperature of matter?
Does heat have other effects
▶ Does Heat Change the Volume of Matter?

The rail roads are made
of iron. In the summer the
Sun heats the rails up,
causing them to increase
their volume. This is called
expansion.
As well as temperature Space for expansion on When substances heat up they Thermometer
change, heat also causes rail tracks. expand.
expansion of materials.
Expansion doesn’t only happen to solids; liquids
and gases also expand when heated. For example,
when hot milk boils, its volume increases and it
flows out of the pan.
The same thing happens to the liquid inside
thermometer tubes. When it is heated by the
surroundings, it expands. You notice this expansion
as a change in the liquid level on the measurement
scale. When the surroundings cool, the liquid
contracts and you see the level drop.
Gas substances also expand. For example, if
you blow up a balloon and place it in hot water, you
will see the balloon swell up more. This shows that
Expansion of rail tracks in the summer. the air inside it has expanded, causing an increase
in its volume.
If, instead, you place the balloon in cold water,
you will see the balloon volume decreasing, as the
air inside it contracts.
Gaps at the ends of steel bridges to allow expansion of

the material A balloon in hot water. A balloon in cold water.

▶ Be Careful With Contraction and Expansion! To fix the lenses in the
metal frame, the frame is
When people manufacture things, or use first heated, and then the
materials, they must be careful to allow for lenses are placed inside.
expansion and contraction. As the frame cools down
it contracts and holds the Metal framed glasses
lenses firmly.
If you pour hot water into a cold glass, the glass
will crack. This is because the cold glass expands
very quickly with hot water.
Substances which are heated and cooled are
always expanding and contracting. Over a long time
this causes them to weaken. For example, rocks
are affected by the changes in temperature of the
seasons. Over the ages they crack, break off, and
then break down into soil and sand.
When engineers plan houses, they must calculate

the expansion and contraction of concrete, metals
and other materials in the buildings.
Car tyres are filled with air. In the summer the
air in the tyres expands, making them much harder
than in the winter months. In this case, some of the
air must be released. In the winter, the tyre must be
filled with more air, since they have contracted and
become flatter.
Rocks break down under the effects of heating

and cooling.
Expansion of Metals
You need: Metal ball and ring device, heater.

Preparation:
1. Pass the ball through the ring. When they are
at the same temperature, the ball just passes
through the ring.
2. Now, heat the ball and try to pass it through the
ring again.
3. What do you observe? Explain.
......................................................................................................................................................
......................................................................................................................................................

What should you do to ▶ Can Evaporation Occur in Cold Weather?
open a glass jar of food?
Why do wet clothes dry even if there is no
sunshine?
Glass jars
2. Evaporation and Condensation

Matter can change
from one state into
another, this is called
a change of state.
Changes of state are
caused by heat.
freezing condensation
After rainfall the wet streets dry after a while,
even when the weather is cloudy.
melting evaporation
As you can see, water evaporates at all
Solid Liquid temperatures. Other liquidsGasalso evaporate at all
A melting icicle temperatures.
▶ Evaporation and Heat freezing cond
▶ Does the Amount of Heat Affect Evaporation?
Just like cologne and water, when liquids evap-
The water in lakes melting
and seas evaporates much eva
orate they absorb energy from their surroundings.
more in the summer than the winter.
melting Solid Liquid
If you drop water on your clothes, they dry much
Solid Liquid faster if you stand in sunlight.
The amount of liquid evaporating is much greater
freezing if the surroundings are hot. This means that as the
surroundings heat up, evaporation speeds up.
melting
▶ Condensation and Heat
Solid Liquid Solid Liquid
If you place some cold water in a glass, after
a while you will see tiny water droplets on the
outer surface of the glass. This is called frost,
freezing
condensation
and is caused when the water vapour in the air
cools on the glass surface and changes to water.
A change of state from a gas to a liquid is called
Liquid Gas
Gas Solid
condensation. Liquid
Cologne evaporates
condensation
evaporation
Liquid Gas Liquid Gas
Gas
evaporation
The substance loses heat when it condenses. ▶ Are Boiling and Evaporation Different?
This heat is given to the surroundings.
The differences between evaporation and
The colder the surroundings are, the faster the
boiling are listed in the table below:
condensation is.
Evaporation Boiling
When the liquid starts

boiling, there is water vapour
Always occurs on
everywhere. Vapour forming
Water vapour condenses the surface of a
inside the water causes
on cold glass liquid.
bubbles which rise to the
3. Boiling water surface.
When you heat water, it warms up, and you see

water vapour coming off the surface. As the water
The temperature of a boiling
heats up, the amount of evaporation increases.
liquid doesn’t change.
Points inside the liquid at temperatures above
The heat given to it is
boiling point expand rapidly, causing bubbles An evaporating
not used to increase the
inside the liquid. These rise to the surface. When liquid may have
liquid temperature, only to
the water is at a temperature of 100°C the surface a changing
change it into vapour. The
starts to bubble. temperature.
liquid stays at the same
The water temperature stays at 100°C until all temperature until all water
the water has been changed into steam. When has been used up.
bubbles are formed all over the water and very fast
evaporation is seen; boiling is occurring. Now the
pressure of the steam at the liquid surface matches
the pressure of the atmosphere. Evaporation Boiling occurs at a fixed
occurs at all temperature that is
temperatures. characteristic of each liquid.
Boiling water: Bubbles within the body of the water Evaporation and condensation

freezing conde
melting evap
Solid Liquid
4. Melting and Freezing ▶ Do Liquids Change Into Solids?
Substances change from one state to another. A change of state from a liquid into a solid is
A change from a solid state to a liquid state is called freezing. For example, if you place some
called melting. For example, if you take an ice tray water into the freezer it will change into ice.
out from the freezer and place it on a table, in time, melting
On very cold days, when it rains, you can see
it will melt and become a liquid.
frozen water on the ground.
Solid Liquid
freezing
Solid Liquid
condensation
melting evaporation
Liquid Gas
Gas
Solid Liquid Gas
Melting ice
evaporation
Liquid Gas
melting
Solid Liquid
On cold days water freezes on the branches of plants
freezing When a substance changes from a liquid state

▶ Is Heat Needed to Melt Solids? into a solid state it loses heat to its surroundings.
Heat
Solid is needed for melting to occur. Place a
Liquid
cube of ice into a glass. Now allow it to stand inside
a container of water. After a while, you will notice
that the water in the container cools down as the
condensation Liquid wax
ice melts. This means that a solid substance, which
drops change
melts, absorbs heat from its surroundings.
into solid
Liquid Gas
Gas wax, as they
flow down the
candle
evaporation
Liquid Gas
Butter melting in a pan A melting iceberg

Boiling Point and Condensation Point
Liquids absorb heat and evaporate at all

temperatures. As the temperature increases, the
amount of evaporation also increases. This reaches
a point where the temperature increases all over
the liquid and evaporation increases. Some points
in the liquid will have temperatures greater than the
surface temperature. These points turn into vapour
and explode, sending bubbles to the surface of the
water. For any pure liquid, the temperature at which
this bubbling happens is called the boiling point,
water boils at 100°C. Even if heating continues
there will be no temperature increase.
Comparing boiling points of two different liquids
The Boiling Points of Some Liquids
Liquid Boiling Point
Water 100 °C
Ethyl alcohol 78 °C
Acetone 50,5 °C
Water boils at 100 °C
Ether 35 °C
When a gas cools, it starts to change from gas
state into liquid state at a certain temperature. This
certain temperature is called condensation point.
The boiling point temperature of a liquid does not
There are many liquids around you. They all depend on the amount of liquid; only on the type of
have different properties, so their boiling points are liquid. For example, a glass of water and a bucket
also different. full of water have the same boiling point.
melting evaporation
Solid Liquid Gas
Changes of state of matter

melting
Solid Liquid
Melting Point and Freezing Point ▶ Are Melting and Freezing Point Temperatures
the Same?
If a solid substance is heated, its temperature Ice melts at 0°C, but water also freezes at 0°C.
increases. At a certain temperature, it starts to Each substance has the same melting and freezing
melt. For example, in a freezer the temperature temperatures. Melting and freezing are reverse
of a piece of ice is below 0°C. If it is taken out processes.
and placed in a warm room, it starts absorbing
heat. The temperature of the ice increases until it
reaches 0°C, at this point it starts melting. While
it melts this temperature (point) does not change.
freezing
water 0°C
melting
Ice absorbs heat, and then melts
The temperature at which a pure solid starts to Some melting and freezing points are given in
melt is called its melting point. the table below:
If a liquid cools, its temperature decreases. At The Melting and Freezing Points of
a certain temperature, the liquid changes state Some Pure Substances
from liquid into a solid. This certain temperature is Melting and Freezing
called freezing point. For example, when water is Pure Substance
Points
cooled to 0°C it freezes to form ice.
Ethyl Alcohol –117 °C
Ether –116 °C
Acetone –95 °C
Mercury –39 °C
Water 0 °C
Lead 327 °C
Copper 1084 °C
Water freezes at 0 °C Iron 1535 °C

1
THE EFFECTS OF HEAT ON MATTER
Write T (true) or F (false) in the brackets at the side of each of the following statements.
1. (......) A change in state from a solid state into a liquid state is called melting.
2. (......) A change in state from a liquid state into a gas state is called boiling.
3. (......) A change in state from a liquid state into a solid state is called freezing.
4. (......) The temperature at which a liquid freezes is called its freezing point temperature.
5. (......) Every substance has the same melting - freezing point temperature.
6. (......) The boiling point temperature is the same for every substance.
7. (......) Substances don’t freeze at their melting temperatures.
8. (......) Water freezes at 0 °C, ice melts at 0 °C.
2
Fill in the blanks with the correct words.

1. ...................... happens when a solid substance absorbs heat and changes melting
into a liquid. freezing
melting point
2. The melting point of a solid is called its .............................................. . temperature
3. .................... happens when a liquid substance loses heat to its surroundings
and changes to a solid. freezing point
temperature
4. The freezing point of a liquid is called its ............................................ .
substance
5. Melting and freezing point temperatures are the same for a ............................
3
Answer the questions below.

1. What is melting?
.....................................................................................................................................................
2. What is freezing?
.....................................................................................................................................................
3. What is boiling?
.....................................................................................................................................................
4. What is condensation?
.....................................................................................................................................................

1
1. Which of the choices below about water is 4. I. Its temperature increases.
incorrect? II. It may change from a liquid to a solid.
BBB
A) It freezes at 0 ºC. III. Its size changes.
B) When you cool water it boils. If heat is given to a substance, which of the
above may occur?
C) It evaporates at all temperatures. AAA Isý maddeleri etkiler
A) I and III B) I and II
D) It boils at 100 ºC.
C) II and III D) I, II and III
5.
2. Mariam twists the metal lid of the
jar, but cannot open it.
What advice can you give to help
her?
AAA Isý maddeleri etkiler

A) Heat the metal lid
B) Heat the glass jar
C) Cool both the metal lid and jar
D) Cool the metal lid
Ahmad is trying to pull a metal ball through a
metal ring.
What should he do to succeed?
I. Cool the ball
3. Bahaddin tries to place II. Heat the ball
a metal marble inside a
III. Cool the metal ring
bottle. But the marble is AAA
slightly bigger than the A) I B) I and III
opening.
C) III D) II
Which of the following
should Bahaddin do to
get the marble inside the
bottle?
CC Isý maddeleri etkiler 6. Which of the below is caused by evaporation?
A) Place the bottle in ice for a while BBB
A) Butter changing into a liquid
B) Heat the marble
B) Cologne spreading everywhere after it is
C) Place the marble in ice for a while and heat
dropped
the bottle
C) Water changing into ice
D) Place the bottle in ice for a while and heat
the marble D) The melting of a candle

1
7. I. Increase in mass 10. Which of the following events causes water on
II. Increase in volume the ground to rise upwards in the atmosphere?
CCC
III. Increase in temperature A) Expansion B) Melting
If you heat up a piece of iron on a heater, C) Evaporation D) Freezing
which of the above changes will you see?
A) I only B) I and II
C) I and III D) II and III
11. I. Freezing
II. Evaporation
III. Condensation
8. What changes does a cooling object cause in IV. Melting
its surroundings? Which of the above is caused by losing heat?
DDD DDD Isý maddeleri etkiler
A) It gains heat from its surroundings A) I only B) II only
B) It cools its surroundings C) II and III D) I and III
C) It doesn’t cause any change in its
surroundings
D) It gives heat to its surroundings
12. I. Melting
II. Freezing
III. Evaporation
IV. Condensation
9. Liquid in glass thermometers are used in
homes and schools. Which special property of Which of the above is caused by heat
liquids make them work? absorption?
A) Evaporation B) Boiling A) I and II B) III and IV

C) Expansion D) Freezing C) II and IV D) I and III

1
13. Hakan wants to separate 16. Metal A is placed on top
two glasses, of the same of metal B, as shown in
material that are stuck the figure. A short time
inside each other. later, the temperature of
Which of the choices metal A drops and that
below will help him? of metal B increases.
BBB Which of the following statements is incorrect?
A) Place the first glass in hot water and the DDD
second glass in ice water. A) Heat has passed from metal A to metal B.
B) Place the first glass in ice water and the B) At the beginning, the temperature of metal
second glass in hot water. A was higher.
C) Place the first glass in cold water and the C) Heat will keep flowing until the temperatures
second glass in cold water. of both metals are the same.
D) Place the glass 1 in hot water and pour D) Heat has passed from metal B to metal A.
some cold water in glass 2.
14. If a hot teapot is placed on a cold table, which 17.

of the following will happen?
A) Heat won’t flow.

B) The teapot will gain heat, the table will lose
heat.
C) The teapot will lose heat, the table will gain
heat.
Which of the changes of state is shown in the
D) The teapot’s temperature will increase.
photograph?
A) Evaporation - Condensation
B) Boiling - Melting
C) Evaporation - Freezing
D) Freezing - Melting
15. Which device should you use to measure the

temperature of a room?
BBB
A) Balance B) Thermometer
C) Calorie D) Joule

2. THE CHANGING STATES
OF WATER IN NATURE
▶ The Different States of Water in Nature 3. Hail: Hail is a frozen raindrop. It can form in
clouds where strong, fast, swirling air currents push
the drops through very cold temperatures. This
The weather is not always sunny. It can be
cools down the raindrops below freezing point, and
cloudy, rainy, snowy or foggy. Have you ever
they form lumps of ice called hailstones. These
wondered how weather conditions happen?
can sometimes be very large and dangerous.
Water sources like seas, lakes, rivers, and
streams are found in the liquid state. The Sun heats
up the water on the surfaces of these sources.
When water absorbs enough energy from the Sun,
it changes into a gas state and rises upwards
through the air. This process is called evaporation.
As water vapour rises it comes into contact with a
cold layer of air, and changes state into tiny liquid
droplets. This process is called condensation.
These droplets and steam form into the clouds you
see in the sky.
1. Water in its liquid

state: The air inside the Hail stones
clouds cools down, the
tiny droplets of water
bump into one another 4. Fog: This is water in its gas state. Sometimes,
to make larger drops of warm water in its gas (vapour) state comes into
water. When the drops contact with a layer of colder air near the ground.
become large and heavy This causes the vapour to change into tiny droplets
enough, they cannot stay of water near the ground. As these water droplets
in the air and fall to the are so tiny they, can float in the air and are called
ground as rain. Rain fog.
2. Water in it is solid
state: If clouds come
into contact with a very
cold layer of air, the water
vapour freezes before
it can change into the
liquid state. This means
it changes from its gas
state directly into the
solid state; producing tiny Snow
ice crystals. A snow-flake may be made of a single
ice crystal or a few of them which join together.
These are so heavy that they cannot stay in the
Fog
atmosphere, and fall to the ground as snow.

▶ The Water Cycle
Water, covers about three quarters (71%) of

Earth’s surface.
Rivers, seas and oceans are always
evaporating. The steam rises into the air as
tiny water droplets, later they fall as rainwater,
returning to the land. So, there is a natural
balance between water in the atmosphere and
land. In the hot summer months there is more
water evaporation, leaving less land water
resources. In the cold winter months there is
more water condensation in the atmosphere,
causing more rainfall. In springtime snow melts
and joins the rainfall, causing more flowing land
water. This water reaches water resources such
as lakes and seas. In this way, the amount of
land water resources are balanced.
This movement and change in state of water
in the atmosphere is called the water cycle.
For the water cycle to continue there must be
continuous evaporation of tonnes of water. This
needs a such a large amount of energy that only
the Sun can provide it
The water cycle

4
THE CHANGING STATES OF WATER
Fill in the empty spaces in the sentences with the correct word from the list below.
water vapour water condensation
water cycle the Sun
1. The movement of water between Earth’s surface and the atmosphere is called the ............................ .
2. ................................. is when a substance in the gas state changes into its liquid state.
3. Steam condenses and forms ................................. in the upper atmosphere.
4. The water cycle is formed with the help of ................................. .
5. There is always a fixed amount of ................................. in the air.
Water Cycle
You need: Heater, beaker, water, glass dish, some ice.

Preparation:
1. Fill the beaker with some water.
2. Cover the beaker with the glass dish and place ice on it.
3. Heat the beaker slowly.
4. Observe what happens to the water.
Write down what you observe.
............................................... . . . . . . . . . . . . . . . . . .
............................................... . . . . . . . . . . . . . . . . . .
............................................... . . . . . . . . . . . . . . . . . .

2
1. Which of the sentences below about the Sun is 4. Which of the sentences below is incorrect?
incorrect?
A) Rain is part of the water cycle.
A) It only affects the growth and development
B) As you travel upwards in the atmosphere,
of animals.
the temperature decreases.
B) It is a light and heat source.
C) Water vapour is not found inside fog.
C) It sends light rays onto Earth’s surface.
D) Condensation and evaporation are reverse
D) It is the source of most of our energy on processes.
Earth.
2. Water found in the liquid state on Earth’s 5. I. Snow - Rain

surface changes into water vapour and rises in II. Rainbow - Lightning
the atmosphere.
III. Cloud - Fog
Which of the sources below can provide this IV. Hail stones - Ice
amount of heat energy?
AAA Su halden hale girer Which of the above is an example of water’s
A) The Sun gas state?
B) Fuels A) I B) II C) III D) IV
C) Nuclear energy
D) Geothermal energy
6. I. Snow
II. Rain
III. Fog
3. Which of the following choices is not a part of In which of the above types of weather do
the water cycle? substances fall from the sky?
DDD BBB Su halden hale girer
A) Freezing B) Evaporation A) I only B) I and II
C) Condensation D) Boiling C) I and III D) II and III

5
HEAT AND TEMPERATURE
Put ‘T’ for true/correct or ‘F’ for false /incorrect in the spaces shown at the start of each sentence.
1. (......) There is no difference between heat and temperature.

2. (......) The measurement unit of heat is the degree Celsius.
3. (......) The water cycle is caused by solar energy.
4. (......) The water in the atmosphere usually falls to Earth’s surface as rain or snow.
5. (......) A cold object in contact with a hot object causes heat to flow from the cold object towards the
hot object.
6. (......) Water evaporates only at 100 °C, its boiling point.
7. (......) Heat flows from a hot substance to a cold substance.
6
HEAT AND TEMPERATURE
Match the answers in the table with the correct statements below.
1. (......) The movement of water between Earth’s

surface and the atmosphere.
Condensation Evaporation Water cycle
2. (......) It happens when water vapour rises in the 1 2 3
atmosphere and changes to water droplets
in the layer of cold air.
3. (......) Our heat and light source. The Sun
4
4. (......) When water absorbs heat and changes to a
gas state.
5. (......) There is always a fixed amount of this in the Heat Temperature Water vapour
air. 5 6 7
6. (......) When a substance absorbs heat it increases.
7. (......) A kind of energy.

7
Do You Know?
An object that it released from rest

drops quickly because of acceleration
due to gravity.
When millions of raindrops fall at Have You Thought About
the same time, they don’t touch one These Points?
another, even if they are blown about by
the wind... A scientist has taken thousands of
photographs of ice crystals, but he
couldn’t find any that were the same...
8
Write ‘T’ for true/correct and ‘F’ for false/incorrect at the beginning of the sentences below.
........ 1. Clouds are formed when water vapour in the air condenses.
........ 2. When you go upwards through the atmosphere the temperature increases.
........ 3. The movement of water between Earth’s surface and the atmosphere is called the water cycle.
........ 4. The amount of water evaporating is always greater than the amount of water falling as rain.
........ 5. The name given to the change of state of water from a gas into a liquid is called evaporation.
........ 6. When steam in the atmosphere freezes in cold air to form crystals, it causes snow to form.
........ 7. The Sun is the source of energy for Earth’s surface.
........ 8. Ocean, sea, river and lake water are all evaporated by the Sun.
........ 9. After it rains, the rain water evaporates again.
........ 10. The Sun provides heat and gives out light.

9
THE CHANGE OF STATE OF MATTER AND ITS IDENTIFICATION
Fill in the blanks with the correct words from the list below.
temperature
water cycle
hail
heat
heat flows rain and snow
cool down
Sun heats melts

light
1. Substances that absorb heat increase their ................................. .
2. ................................. from a hot object towards a cold object.
3. The movement of water in the atmosphere is called the ................................. .
4. Surface water evaporates due to the energy of the ..................................
5. The water in the atmosphere usually returns as ................................. to the ground.
6. The Sun both provides................................. and ................................. us.
7. ..................................... is a frozen raindrop.
8. After sweating you ........................ this is because the sweat takes ........................ from your body.
9. If you hold a piece of ice in your hands, the ice absorbs heat from your hands and ............................ .

1. Forces
2. Let’s Get To Know Magnets
3. Friction Force
CHAPTER 3 | FORCE AND MOTION 59

1. FORCES
What is force? When do you apply a force on

objects?
When you push or pull an object, you apply a
force. A more general definition of force is as
follows:
Force is an effect which can:
You apply force when you A magnet pulls the pins.
▸ start motion comb your hair.
▸ stop motion
▸ change the direction of motion 1. Contact Forces
▸ change the speed of motion
The force caused by contact between two
▸ change the shape of an object
objects is called contact force. If you have two
objects applying force by touching each other, then
Force is a push or pull on an object
the objects apply contact forces upon each other.
Pulling
Pushing force
force
Contact forces
There are many examples of how forces affect When you push, pull, hold, or, lift an object by
objects around you. touching, you are applying contact forces.
Force causes an object to Force can cause an object to

move. change its shape.
When you kick, you apply a If you push the cart, you When you hold a glass you apply a contact force.
force on the ball. move it.

2. Non-Contact Forces
To move an object, a force does not always have
Which of the choices below about forces is
to be in contact with an object. Some forces may
incorrect?
cause objects to move, without any contact with
it. This type of force is called a non-contact force. A) The force that acts towards the centre of the
Earth is called gravitational force.
Objects, which are released from rest at a height,
fall to the ground by the action of a non-contact B) A force is needed to push, pull, bend, and
force called gravitational force. squeeze objects.
C) The action that causes objects to move, stop,
A stone released from rest at a height, a piece of
change their speed and shape is called a
fruit falling from a tree, a drop of rain, a water drop
force.
from a tap, all fall due to the action of gravitational
D) Pressing a television button is an example of
force.
a non-contact force.

Which of the following statements about

forces is correct?
Gravitational force pulls objects towards the ground. A) Air has a friction force.
B) Magnetic forces only act on iron.
C) Forces can increase the mass of an object.
Materials like iron, nickel, and cobalt can D) The magnetic force is a contact force.
be made to move by the non-contact force of
magnetism.

I. Dough
II. Sponge
III. Spring
Non-contact forces
Which of the above objects return to their
normal shape after being squashed by a force?
If you rub your hair with a balloon or a comb,
then hold either of them near to your hair, they will A) I and II B) II and III
cause your hair to rise. This is a non-contact force.
C) I and III D) I, II and III

1
FORCES
Look at the pictures below. Underneath them, write down if the force which causes the movement is a
contact or non-contact force.
1 2 3
.......................... .......................... ..........................
4 5 6
.......................... .......................... ..........................
7 8 9
.......................... .......................... ..........................

1
1. Which of the children below is using the 4. Which of the following is an example of a
action of a force to stop a moving object? non-contact force?
AAA Kuvvetler DDD
A) Ahmad is catching a falling apple A) Lifting up a rubber
B) Hassan is pushing a chart B) Opening a window
C) Zahra picks up fruit from the table C) Closing a bag
D) Murad is opening a cupboard door D) Dropping a walnut on the floor
2. The gravitatitonal force is a kind of ............... . 5. Which of the following choices is an example
of a non-contact force?
Which of the following correctly completes
the sentence above? A) Pushing a trolley
CCC Kuvvetler
A) Contact force B) Holding a book
B) Pushing force C) Picking up a teapot
C) Non - contact force D) A leaf falling to the ground
D) Touching
3. 6. Two groups of children play tug-of-war. Each

group holds one end of a rope and try to pull
the other group over a line drawn between
them.
What type of effect does the force have on
each group of children?
I II III
A) Pushing B) Pull
In which of the above pictures does a
non-contact force act? C) Push - Pull D) Slowing down
BBB Kuvvetler
A) III only B) I and II
C) II and III D) I and III

1
7. I. Increase in speed 10. When a force is applied to an object it causes

II. Increase in mass it to ...........I......... or to ...........II.......... .
III. Change in shape Which of the following is the correct order to
complete the sentence above?
Which of the above effects may be caused by AAA Kuvvetler
a force? I II
DDD Kuvvetler
A) I only B) I and II A) change its shape move
C) II and III D) I and III B) increase its mass change its shape
C) movement increase its mass
D) change its shape increase its mass
8. Which of the choices below about gravity is 11. I. Sitting on a chair

incorrect?
BBB Kuvvetler II. Pressing the brakes of a car
A) It acts towards the centre of the Earth III. Falling of a stone from a height
B) It is a contact force The actions above are due to contact forces
and non-contact forces. Which of the choices
C) It is the force that causes apples to drop
below correctly groups them?
onto the ground BBB Kuvvetler
D) It is a force that acts on all objects on the Contact forces Non-contact forces
Earth
A) II and III I
B) I and II III
C) II I and III
D) III I and II
9. Which of the events below is slowed down by

gravity?
CCC Kuvvetler
A) A ball rolling down a slope
B) A child sliding down from the top of a hill on
skies.
C) A stone thrown upwards
D) An orange falling from a tree

2. LET’S GET TO KNOW
MAGNETS
Magnets attract materials made of iron, nickel If two magnets are brought together, the same
and cobalt. These materials are called magnetic type of poles push each other away or repel.
materials. Magnets don’t attract other types of
materials. This means we can use magnets to
separate magnetic materials from non-magnetic
materials. For example, sand and iron filings can
be separated by a magnet.
Magnets are found in nature and can also be
manufactured. Magnets are classified by their
shapes such as: cylindrical magnets, bar magnets,
ring magnets, horse shoe magnets, U-shaped .
magnets. Look at the picture below. What types of
magnets do you see?
The same poles (like poles) repel each other
Opposite poles pull towards each other or attract.
If two magnets are

brought near each other,
sometimes they will push
each other and sometimes
they will pull each other.
Whether they push or pull
each other depends on the
The opposite poles (unlike poles) attract each other
part of a magnet called its The magnetic force is
poles. Each magnet has strongest at the poles.
two different poles.
The force of a magnet is strongest at its ends. If a magnet is cut in half, its magnetic properties
Each magnet has a north (N) pole on one end and don’t change. Each half will just form a new magnet
a south (S) pole on the other end. and new north and south poles.


Magnets have many technology and everyday
uses.
▸ On cupboard doors
▸ Fridge doors
▸ Bag clips and mobile phone cases
▸ Decorations for fridge doors
▸ Technology products like loudspeakers and
compasses
Magnets may affect the working of computers,
mobile phones, credit cards, and TV monitors. They
must be kept away from these types of technology
items.
A compass needle is a magnet.
A magnet applies a non-contact force to separate

iron filings.
The Earth has magnetic poles, so you can use

compasses to find direction.
Magnetic Force
You need: Two bar magnets, a piece of string.

Preparation:
1. Suspend a magnet at its centre using a string on a support.
2. Let it line up in the north-south direction.
3. Mark the poles N and S on the magnets (If they are not marked).
4. Bring the S pole of the other magnet near the S pole of the suspended one. Do they repel each other?
5. Repeat step 4 with the N pole. What do you observe?

CAREFUL!
Magnets may damage some high technology goods
like TV’s, computer screens, credit cards, cell phones
and CD’s. Don’t bring these goods near magnets.
2
LET’S FIND OUT ABOUT MAGNETS
artificial loudspeaker attract repel
magnets two little contact iron

Fill in the blanks with the correct words from the list above
1. When a magnet is cut in half .......................... magnets are formed.

2. .......................... damage some technology items.
3. The two like poles of a magnet.......................... each other, the opposite poles of a magnet ..........................
each other.
4. Magnets are found inside a ..........................
5. Magnets attract .......................... , cobalt, and nickel materials.
6. .......................... magnets are manufactured in different shapes depending on what its use will be.
7. Magnets act on materials by a non .......................... force.
3
LET’S FIND OUT ABOUT MAGNETS
Read the sentences below and place a , if it is correct and a  if it is incorrect.
 1. The N pole of a magnet attracts the N pole of another magnet.
 2. Magnets are found in nature.

 3. Magnets act on all materials with a contact force.
 4. Magnets don’t attract iron materials.
 5. Magnets have one N pole and one S pole.
 6. Magnets are not used in everyday life.
 7. Magnets damage some technological goods.
 8. Magnets don’t attract wood, rubber or paper objects.

2
1. In which of the following items are magnets 4. I. Wood
not used? II. Iron
A) Fridge decoration III. Glass
B) Loudspeakers Which of the materials above are not attracted

to magnets?
C) Compasses
A) I only B) I and III
D) Pencils
C) II and III D) I, II and III
5. Every magnet has a north (N) and a south (S)

pole. The same poles repel each other, while
the opposite poles attract each other.
2. Which of the following choices about magnets Which of the shapes below can be made by
is incorrect? bar magnets?
DDD MIknatýslarý tanýyalým
A) Magnets apply force upon each other. A) NNN SSS SSS NNN
N S S N B) SSS NNN NNN SSS
S N N S
B) Magnets act by non-contact forces.
C) NNN SSSS D) NNN SSS NNN SSS
N S N S
C) When magnets are broken, they lose their N
SSS
magnetic properties. NNN
S
N
D) Each magnet has two poles.
6. A magnet is cut in half,

N S as shown in the diagram.
3. In the diagram below, which of the magnets

Which of the following choices is correct
repel each other?
about the magnets produced?
BBB
N SA) S N N S S N A) One half of the magnet will have a north
N N S SS S N N
pole, the other half will have a south pole.
S
N SB)
N NSN S
S S SNN
N S
S N
N N S
B) Each half of the magnet will have a north
N N S S
S NC) S
NSS S NN
S NNS S
SSN
N N N
NN S
S S N pole and a south pole at each end.
C) The magnet lost its properties when it was
S N ND) SS N NNN S NS
SS SN
N N NS S
cut in half.
N SS
S
N
N
S N
S SS
N
NN S N D) The two halves of the magnet cannot be
S N S N cut in half again.
N S N S
S N S N
S N S N
2
7. Which of the goods below may be damaged if 10. Which of the forces, shown in the diagrams, is
placed close to a magnet? an example of a contact force?
AAA CCC
A) Computer B) Glass A) B)
C) Knife D) Rubber
C) D)
8. A pupil drops iron

filings into a glass
of water. A bar
magnet has been
placed under the
glass, as shown in
the diagram. When
the pupil moves the
magnet, the iron filings also move.
Which of the questions below cannot be
answered using this experiment?
CCC
A) Can a magnet affect the iron filings
through glass?
B) Can a magnet attract iron filings?
C) Can magnetic forces travel through a
vacuum?
D) Can magnets affect magnetic substances
in water?
11.
N S N S N S S N
The arrows above show how the magnets in

the diagram attract and repel each other.
9. Which of the items below use magnets to I. Different poles attract.
work? II. Same poles repel.
AAA
A) Fridge door III. Magnets don’t affect each other.
B) Electric bulb Which of the sentences above are incorrect?

AAA
C) Tap A) III only B) I and III
D) Hammer C) II and III D) I and II

3. FRICTION FORCE
1. Friction Force It is difficult to push a heavy box along the floor,

this is because there is a friction force between the
Friction force makes movement difficult for box and the floor.
an object. This force is caused when an object
touches a surface, like the ground.
Friction force makes it difficult to move the box
2. Air and Water Friction

A friction force acts:
When you are walking or running, there is a
▸ On a moving object to stop or it slow down. friction force between your feet and the ground.
▸ Between two surfaces. There is also a friction force between the air and
▸ In the opposite direction to the motion. your body.
You can feel the friction force caused by the air,
if you do an experiment.
Friction force always acts in the opposite

direction to the motion of the object.
Different types of surface can make moving an
object difficult or easy.
Air Friction
You need: Two pieces of paper of the same size.

Preparation:
1. Screw one of them up into ball by crumpling it up, as
shown in the figure.
2. Release the crumpled paper ball and the sheet of paper
Paper ball
from the same height at the same time.
A sheet of paper
3. Which of them falls first? Why?

Cars, planes and mo- Reducing friction:
torbikes are designed to
Friction causes the parts of a
decrease the effect of
machine which rub against each
air friction. This makes
other to heat up and wear out.
vehicles go faster.
Therefore, oil is used to re-
Parachutes are de- duce friction. Using roller bear-
signed to use as much ings, wheels, and balls are oth-
air friction as they can, er ways of reducing friction.
to slow them down. as Smooth surfaces have low fric-
Parachutists use the air
much as possible tion, but rough surfaces have high
friction to slow down.
friction. So smoothing also reduces friction.
Water friction also affects water vehicles; making
it difficult for them to speed up. The fish’s body is smooth and slippy; this reduc-
es water friction.
Sea creatures are designed to reduce water friction

Water friction
Birds also have a body shape that reduces air
Water vehicles are designed to decrease water friction, resistance. Their feathers are also designed to use
so that vehicles can move faster. the air friction.
3. Friction Forces in your Life
Uses of Friction;
▸ Walking on the
ground
Meteorites, enter the
▸ Writing on a surface
Earth’s atmosphere at
▸ Cleaning the floor high speeds, are burnt
▸ Swimming up as they enter, and are
▸ Flying destroyed. The Moon
Friction forces sometimes make our lives doesn’t have any air at-
difficult, but sometimes they make our lives easier. mosphere, so meteorites
keep hitting it, causing gi-
Snowy ground has a low friction, so it is difficult ant holes on it. If Earth did
to drive a car on snowy ground. This is because the not have an atmosphere,
friction between the snowy surface and the car’s it would have the same
tyre is too low. Birds have a body
problem as the Moon.
shape and surface
Friction can be increased using a chain, this will which reduces air
help the car drive better on ice. resistance.

4
FRICTION FORCE
Why can’t people walk easily on ice? ____________ Why must a chain be fitted to car tyres on
___________________________________________________________________ snowy roads? ____________________________________________
___________________________________________________________________ ___________________________________________________________________
Direction of
motion
Sandpaper Glass Cloth
The boy has difficulty in pushing the furniture. Place the surfaces above in order of highest
What advice can you give him to lower the friction to lowest friction, for the car to drive
friction? over.
___________________________________________________________________ _____________________________________________________________________
___________________________________________________________________ _____________________________________________________________________
Friction of Air and Water
You need: 2 clear bottles, 2 marbles, water.

Preparation:
1. Fill one of the bottles with water.
2. Place the bottles on the same surface.
3. Hold the marbles at the same level from the tops of the bottles.
Water
4. Release the marbles at the same time, so that they fall into the bottles.
5. Observe carefully what happens.
What did you observe? Which marble landed on the bottom first? Why?
.......................................................................................................................................................

3
1. Which of the choices below is not helped by 4. Which of the following is designed to increase
friction? air friction?
CCC
I. Car
A) Stopping a car with its brakes.
II. Parachute
B) Holding a person walking down a sloped III. Plane
surface to stop them from falling and BBB
rolling down it. A) I only B) II only
C) Machine parts wearing out by rubbing C) I and III D) II and III
against each other.
D) Reading a book.
2. Which of the following decreases friction?

I. Spreading oil on a surface over which an
object is to be pulled.
II. Smoothing a surface over which an object
will move.
III. Roughening a surface over which an 5. Noor places two similar
object will move. bottles next to each
AAA other, filling one with
A) I and II B) I only liquid and leaving the
C) I and III D) II and III other empty. She then
drops two marbles from
the same height into the
open tops of both
bottles at the same time.
Which of the choices below about Noor’s
experiment is incorrect?
CCC
3. I. Ship A) The marbles reach the bottom of the
II. Plane bottles at different times.
III. Car B) The marble that falls into the empty bottle
reaches the bottom first.
Which of the vehicles above has both air and
water friction acting on it? C) Air resistance is greater than liquid
AAA resistance.
A) I only B) I and II
D) The liquid resistance slows down the
C) II and III D) I, II and III motion of the marble.

5
FORCE AND MOTION
P A R A C H U T E M W Y X T D
D T Z X F C O N T A C T T A S
P L A N E M D X A L Y Q P V C
X G M G H I Z K Q P L P U L L
L A O W F R I C T I O N N M T
W A T E R R E S I S T A N C E
A M I A W E M G R O U N D M R
T A O R C S N Z O G G C T H O
E X N V J I Z X N O R T H Y L
R G F O A S O U T H Y H V D L
O B J E C T T A Q Y G N T F P
T W M T Y A W J Q G A A M O U
A V M A G N E T I S M H J R S
I Y H F Y C Q A K D X O W C H
R Q M S P E E D U P G T Z E J
FRICTION FORCE GROUND SOUTH

NORTH AIR PLANE CONTACT
WATER PARACHUTE SPEED UP MAGNETISM
PUSH OBJECT MOTION PULL
1. Simple Electric Circuits
CHApTeR 4 | eleCTRICITy IN yOuR lIfe 75

1. SIMPLE ELECTRIC CIRCUITS
1. Let’s Change the Brightness of a Light Bulb Look at the circuits below. What are the
differences between the brightnesses of the
lamps?
A simple electric circuit includes a cell, a bulb, The first includes only one light bulb and one
a switch, and connection cables. These parts are cell. In the second circuit there are two light bulbs.
called circuit components. This makes both bulbs less bright than the bulb in
the first circuit diagram.
To light up a bulb in a simple circuit, all the com-
ponents must work. The properties and values of
the components in the circuit change the bright-
ness of the light bulb. This means that the bright-
ness of the light bulb changes in each circuit.
Open circuit
As there are many light bulbs, the cell in the

circuit may not have enough energy to light up the
bulbs.
Closed circuit
The brightness of bulbs in a simple circuit de-

pends on the number of bulbs and the number of
cells. As the number of bulbs in the circuit increas-
es, each light bulb gets less energy. This means
each light bulb shines less brightly.
The cell in the circuit may not have enough energy to

light all the bulbs

Let’s Change the Brightness of the Bulbs
You need: 3-4 bulbs, connection cables, dry cells, switch.

Preparation:
1. Set up a simple electric circuit.
2. Connect the bulbs one by one to the circuit and observe the changes in the bulbs.
▶ Changing the Number of Cells

In this type of circuit, increasing the number of cells will
make the light bulbs shine brighter. Decreasing the number
of cells will make the bulbs less bright. When this happens,
the bulbs are said to be dimmer. In the first circuit there is one
cell and one light bulb. In the second circuit one more cell is
added. So, the brightness of the light bulb increased.
Look at the brightness of the bulbs below.
Let’s Change the Number of Cells
You need: 2 dry cells, connection cables, bulbs, switch.

Preparation:
1. Set- up a simple electric circuit.
2. Connect the dry cells one by one to the circuit and observe the changes in the bulbs.

2. Electric Switches and Circuit Switches All electrical devices have a plug. This is fitted
into an electric socket on the wall. In this way, the
electrical devices are connected to the city elec-
tricity (mains supply).
Electric appliances used in houses work with
mains electricity. Electricity is made in power
stations and is brought to homes by thick metal
wires called cables.
Electric socket
Electric switch
Electric switches are placed on the walls to
Electric energy is carried to cities through thick cables.
switch the lamps in the rooms on or off. When a
People use electricity by connecting the ends of switch is closed in a house circuit, the circuit is
these cables into electrical switches and sockets. said to be completed. A complete circuit works.

3. Let’s Look at Circuit Symbols
There are different types of circuit components.
Each component has its own symbol that identifies
it.
▸ Symbols are simple, easy to draw, take up little
space and can easily be recognised.
▸ Circuit symbols are recognised and agreed on
all over the world.
There are many different types of cells/batteries and

light bulbs.
The following table shows the symbols used for ▶ Let’s Draw A Simple Circuit Diagram
the components in simple circuits.
In a circuit diagram, only circuit symbols are
used. Pictures of the circuit components are not
used.
Circuit element Picture Symbol
A circuit diagram is drawn by placing the
positions of all circuit components in the right
order, using their symbols.
A circuit photograph is shown below; its circuit
Cell diagram is drawn below the photograph.
+_
Open switch
Switch
Closed switch
Light bulbs
A simple electric circuit
switch
cells
Electric cable cables
+
–
+
light bulb –
A circuit

A photograph of another simple electric circuit
made of two batteries, three bulbs, a switch, and
connecting cables. Below the photograph is its
circuit diagram. In which of the circuits below will the bulbs
light up? Why? Explain your reason.
A)
.............................................................................
A simple electric circuit
.............................................................................
B)
+ +
– –
+ +
– –
.............................................................................
A circuit diagram to show the circuit in the photograph
above. .............................................................................
▶ Let’s Make Some Circuits Work C)
There may be many reasons why a simple circuit

doesn’t work or its light bulb doesn’t shine.
Some of the reasons why circuits don’t work are
explained below: .............................................................................
▸ The bulb may be burnt out .............................................................................
▸ The cell may be used up.
▸ There may not be enough cells in the circuit. D)
If the switch is open, the circuit has not been
completed, so it won’t work.
▸ The light bulb may not be connected well in its
socket.
▸ If the wires are snapped inside their covers, the .............................................................................
circuit has not been completed.
.............................................................................

The switch is closed, but there is no cell. This circuit doesn’t work because the switch is open.
So this circuit doesn’t work.
A circuit with a broken wire doesn’t work. The switch is closed, but there is no bulb.
A broken wire is usually hard to find, since wires are So this circuit doesn’t work.
placed inside plastic covers.
There is a bulb, but the cells are connected opposite to There is a bulb and battery connected.
each other. So this circuit doesn’t work. The switch is closed, so the circuit works.

1
SIMPLE ELECTRIC CIRCUITS
Place the words on the notes below into the correct sentences. 1- 8
open ulb ite switch

light b oppos
al r r
identic dimme cell brighte
1. A ........................................ is a circuit component that lights up.
2. The buttons you press to turn on radios and TV’s has the same function that a ..................... does in a
simple circuit.
3. If the switch in a simple circuit is ................ the light bulb doesn’t light up.
4. If the number of batteries is fixed in a circuit, but the number of bulbs is increased, the bulbs become
................ .
5. If the number of bulbs is fixed in a circuit, but the number of batteries is increased, the bulbs become
................ .
6. A ................ is shown by the symbol in a circuit diagram.

+ _
7. Bulbs that are the same as each other are called ................ bulbs.
8. In an electric circuit, the batteries are placed with their ............................... poles connected.

2
SIMPLE ELECTRIC CIRCUIT SYMBOLS
The circuit diagram below has incorrect symbols drawn on it. Re-draw the circuit diagram with the
correct symbols.
+
–
3
SIMPLE ELECTRIC CIRCUIT
Match the correct circuit diagram to its photograph.
+ –
2 –
+
–
+
+ –
3 –
+ +
– –
+
+ –
4
Write T (true) or F (false) in the space at the start of the following statements.
[......] 1. The symbols for electrical components change from country to country.
[......] 2. A battery case is a box which can hold many cells.
[......] 3. If the number of batteries in a circuit is fixed, while the number of bulbs is increased, the
bulbs get dimmer.
[......] 4. If the switch in a circuit is open the bulb doesn’t light up.
[......] 5. A switch is shown by the symbol ( ) in a circuit diagram.
[......] 6. If the number of bulbs in a circuit is fixed, while the number of batteries is increased, the
bulbs get brighter.
[......] 7. The light bulbs in your room work from the mains electricity supply.
[......] 8. Electric buttons on the walls act in the same way as switches in simple circuits.
5
Look carefully at the circuit diagrams below. Write down whether the bulbs light up or not, giving your
reason.
......................................... .........................................
......................................... .........................................
......................................... .........................................
......................................... .........................................

6
Look at the circuit diagrams below and write down the number of circuit components present in each
circuit.
+– +– +– +–
–+ –+ –+ –+
Number of bulbs: ................ Number of bulbs: ................
Number of batteries: ........... Number of batteries: ...........
Number of switches: ........... Number of switches: ...........
7
Look carefully at the electric circuits and draw their circuit diagrams, using symbols.

8
THE ELECTRICITY IN YOUR LIFE
E L E C T R I C X B U L B P
N W D I A G R A M U X R X P
G E N E R A T O R L Q Y Z O
I P H X Q P S Y M B O L P S
N E G A T I V E W S P J Z I
E L E C T R I C S O C K E T
E U X A Z H C I R C U I T I
R Y W B L I G H T K U C Q V
Q H P L U B A T T E R Y Z E
X R Y E Q X S W I T C H R H
W T E L E V I S I O N P W J
SWITCH BATTERY BULB ELECTRIC
CIRCUIT GENERATOR SYMBOL LIGHT
BULB SOCKET CABLE DIAGRAM TELEVISION
ELECTRIC SOCKET NEGATIVE POSITIVE ENGINEER

1
1. A student is testing the effect of varying 3. Which of the following goods uses electrical
the number of batteries in a circuit on the energy to communicate?
brightness of the light bulbs. CCC
A) B)
To carry out this experiment, which of the
following pairs of circuits should he use?
+– +– +– +–
A)
C) D)
+– +–
B)
+– +–
C)
+– +– +–
D)
4.
+– +– +–
2. In which of the following circuits does the light
bulb switch on? Which of the following descriptions I to IV,
DDD about the circuit shown is correct?
A)
+–
B) +– +– I. It is an open circuit.
II. It is a closed circuit.
III. The light bulb is on.
+– +– +– +–
IV. The light bulb is off.
C) D) AAA
A) I and IV B) II and IV
C) I and III D) II and III

1
5. If one of the cells is +– +– 8. I. Allows electrical energy to travel to light bulb
removed from this II. Allows connection of a light bulbs
circuit what effect will it
III. Makes the circuit turn on and off
have on the circuit?
IV. Produces electrical energy
A) The bulb won’t light up.
Which of the above is the function of an electric
B) The bulb gets dimmer. cable?
C) The bulbs gets brighter.
A) III only B) I and II
D) No change in the circuit.
C) I only D) I, II, III and IV
6. Which of the matched pairs below is incorrect?
Component name Picture Symbol
A) Connecting cable
B) Bulb
C) Switch
D) Cell
+–
9.
II
I III
Which of the choices below gives the correct

names of the components in the order I, II and
7. Which of the symbols below is incorrect? III in the circuit diagram?
A) Switch - light bulb - Cell

B) light bulb - Cell -Switch
C) Cell - Switch - light bulb
D) Cell - light bulb - Switch

1. Journey Through the
Cosmos Moon
2. Motion of the Earth and Earth
the Moon Sun
CHApTeR 5 | THe eARTH, THe SuN, ANd THe MOON 89

1. JOURNEY THROUGH
THE COSMOS
1. The Shape of the Earth, Sun, and Moon
Ever since ancient times, man has wondered

about the Earth, the Sun, the Moon, and the stars
they saw in the sky at night.
There were many beliefs about the shape and
position of the Earth in ancient times, but they were
not based on scientific measurements.
Some of these beliefs were that Earth was the
shape of a flat tray, or that it was surrounded by a
To observe the Sun, Moon, and other heavenly bodies
protecting cover. very powerful telescopes are used.
The Earth has a spherical shape. A photograph

of the Earth shows that it looks like a big blue ball.
The Sun and Moon
are also spheres, like the
Earth. A photograph of
the Sun shows it looks
like a much bigger yel-
low ball. A photograph of
the Moon shows that it
In ancient times people believed that Earth was as flat looks like a much small-
as a tray. er yellow ball. This is be-
cause it acts like a mirror Photograph of the Earth
Through the ages people have built telescopes and reflects light from from space.
to find the shape, size, and distance apart of the the Sun.
Earth, Sun and Moon.
About 1000 years ago an astronomer called
Biruni believed that the Earth was a sphere and
used mathematics to work out its circumference
and radius. The value of the radius he calculated is
only 16.8 km different than the modern value.
Today our developed scientific society has
allowed man to find the size and shape of the
Earth, Sun, and Moon accurately by measurement.
Photographs of these nearby heavenly bodies
have been taken. Today there are many scientific
laboratories observing the stars. These are called
observatories. In these laboratories very advanced
telescopes are used to observe the Cosmos. Some
telescopes have been sent into space to observe
the heavens. They are fixed onto satellites and can
The Sun and Moon have spherical shapes.
observe the stars from space.
The Sun is so bright Although the Sun is so much larger than the
that it is harmful to look Earth, it looks smaller. The reason for this is that it
at it with the naked eye. is so far away. The Sun is tens of millions of times
You must wear special larger than the Moon, but they look the same size
glasses to look at it. to you. The reason is that the Moon is much closer
to the Earth. This means the giant Sun always looks
much smaller than it really is.
Never look at the Sun

without special glasses.
The volume of the Earth is 64 times greater than that of

the Moon.
2. Which is Farther Away? Sun
The size of the Sun is very much greater than

the Earth. The radius of the Sun is about 109 times
bigger than that of the Earth. This means the
volume of the Sun is about a million times as big as
that of the Earth. The Sun is larger than the Earth,
and the Earth is larger than the Moon. The size of
an object depends on how far away it is. About
Look at the picture below. Which is bigger, the 150 000 000 km
Sun or the airplane.
About
320 000 km Moon
Earth
When you look at an object from far off, it looks a lot The distance between the Earth and the Sun is very
smaller. This is why the Sun seems smaller than the much more than the distance between the Earth and
airplane. the Moon.

1
JOURNEY THROUGH THE COSMOS
Write T (true) or F (false) in the boxes shown for the following statements.
True False
People have sent rockets into space to

1. observe the cosmos.
2. The Earth is as flat as a plate.

3. Looking at the Sun doesn’t harm your eyes.
Photographs taken in space prove that
4. the shape of our Earth, Sun, and Moon are
spheres.
Thousands of years ago people believed that

5. the Earth was flat.
6. The Earth is greater than the Moon.
7. The Earth is larger than the Sun.
8. The Sun is bigger than the Earth.
When objects are far off they look bigger,

9. when you get nearer they look smaller.
The Sun is much further away from the Earth

10. than the Moon.
Scientists have built laboratories to observe

11. space. They are called observatories.
The instrument used to observe the stars is

12. called a telescope.
13. The Sun only warms up the Earth.

2
observatories bigger telescope space spherical
artificial satellites the Earth large small
Fill in the blanks with the correct words from the list above.
1. People have built ...................... to look at events in the night sky.
2. The instrument used to observe the cosmos is called a ...................... .
3. The Earth and heavenly bodies are in ...................... .
4. The Sun doesn’t only warm ...................... .
5. ...................... are launched into space by rockets.

An observatory
6. The shape of the Moon is...................... .
7. The Earth is ...................... than the Moon.
8. Distance affects whether an object appears ...................... or ...................... .
3

1. What did ancient people do to observe space?
......................................................................................................................................................
2. What were ancient people’s beliefs about the shape of the Earth?
......................................................................................................................................................
3. What made people believe that the Earth, Sun, and Moon were shaped like spheres?
......................................................................................................................................................
4. How are heavenly bodies observed?
......................................................................................................................................................
5. What are the shapes and sizes of the Earth, Sun, and Moon?
......................................................................................................................................................

1
1. Which one is the shape of the Earth? 4. About how far away is the Sun from the Earth
in km?
A) Sphere B) flat CCC
A) 50 million
C) Triangle D) Rectangle
B) 100 million
C) 150 million
D) 200 million
5.
2. Which of the following choices has placed the

sizes of the Earth, Sun, and Moon correctly?
A) Earth > Sun > Moon

B) Sun > Earth > Moon
C) Sun > Moon > Earth
D) Moon > Sun > Earth
A school girl designs small scale models of

the Earth, Sun and Moon. She places them at
small scale distances to complete the model.
Which of the heavenly bodies should be in
place of balls I, II, and III in this model?
CCC
I II III
3. What is the name given to a laboratory built to A) Earth Sun Moon
observe the stars? B) Sun Moon Earth
A) Mint B) Library C) Sun Earth Moon
C) Observatory D) Astronaut D) Earth Moon Sun

2. MOVEMENT OF THE EARTH
AND THE MOON
1. The Earth Never Rests axis
Objects on the surface of Earth make many dif-

ferent types of motion.
You live on the Earth’s surface, but you don’t feel
it moving. However, this does not mean that it is
at rest. The Earth never rests; it turns around itself
and also moves around the Sun. If you hold a ball at
the same position, but turn it around its own centre,
it is called spinning. This is the type of motion the
Earth carries out.
The Earth takes 24 hours to spin about its own centre.
Night-time Daytime
Daytime and night-time are caused by the Earth spinning

The motion of a Ferris wheel and carousel can be felt. about itself, turning towards, then away from sunlight.
As the Earth’s spins, darkness on its surface is
While spinning, a slowly lit up, as the surface slowly turns towards
complete rotation of the the sunlight. However, the bright surfaces are also
Earth about itself takes turning away from the sunlight, to become slowly
24 hours; this is called 1 darker. If the Earth didn’t spin about itself, one half
day. So 1 day = 24 hours. of it would always be night-time and the other half
During a single rotation, always daytime.
both daytime and night-
time will form. Daytime 2. The Sun and the Earth
forms on the side of the
Earth that faces the Sun, Early in the morning, when the Sun rises from
and is lit up by sunlight. the east it keeps on getting higher in the sky until
The side of Earth facing 12.00 pm, noon. After this, it sinks slowly into the
away from the Sun will west and disappears. If you observe this, you may
not be lit up by any of think that the Sun is moving. This is because you
The Earth spins about
the Sun’s light; it will be itself like a spinning ball. are looking at the Sun from different places in the
in darkness, this is night- sky. Really, it is the Earth that is moving around
time. itself.

The Earth spins about itself, but it also moves
around the Sun; a path around an object is called
Noon an orbit. The Earth takes one full year to orbit the
Sun. As the Earth orbits the Sun it causes four
Sunset seasons to form.
Sunrise
3. The Moon’s Movement
The Moon is always in motion. Like the Earth, it
has two types of motion. It spins about itself and at
the same time it moves around the Earth; the Moon
It appears that the Sun is moving all day long. orbits Earth.
When you take a journey in a car, the surround-

ing houses, trees, and hills appear to be moving.
However, it is you who are moving. The car can be
compared to the movement of the Earth and the
surroundings may be compared to the Sun.
In 24 hours both daytime and night-time are
formed. The face of Earth turning away from the
Sun is in night-time, the other face looking towards
the Sun is in daytime. This is always changing, be-
cause the Earth is always spinning. The beginning
of night-time and daytime have special names.
Sunrise is the time in the morning when the Sun
appears or full daylight arrives.
Sunset is the time when daytime is just chang- The Moon and stars
ing into night-time.
4
1 3
Moon
Earth
Sunset
The Earth spins in the direction from west to Sun
east. This means that the Sun rises in the east.
Since the Sun rises in the east, mornings in eastern
parts of any country start earlier than those in
The Earth spins about itself, causing night and day.
western parts. Noon is the brightest time of the 1. The Earth turns (spins) around itself
day; at this time the Sun is overhead. As it gets later 2. The Earth moves (orbits) around the Sun (red orbit)
in the afternoon, less and less sunlight comes onto 3. The Moon spins around itself
the same position and the sky gets darker. Late in 4. The Moon moves (orbits) around the Earth (blue orbit)
the afternoon, the Sun sets.
The Moon takes 29 Moon 1. New Moon Phase
days to orbit the Earth. When the Moon is be-
It also takes 29 days to Point
A tween the Sun and Earth,
A
spin about itself. This it is a shape called the
means observers on new Moon. In this phase
the Earth always see Earth
A the Moon is invisible.
the same face of the
Moon. A
A
The Moon is invisible during
the new moon phase.
4. The Shape of the Moon Changes

The Sun is a light source, this means it is always
observed to be a perfect round shape. The Moon is
not a light source, it just reflects the Sun’s light. On
different nights, the Moon appears to have different
shapes. If the Moon were a real light source, it The new Moon phase.
would always appear to be a perfect circle, like the
2. First Quarter Phase
Sun.
In the first quarter
phase, the right half of the
Moon can be seen on the
Earth. Its shape appears
Moon like the letter ‘D’. This
phase forms seven days
after the new moon.
Sun
Appearance of the Moon in
the first quarter phase.
Earth
Here light from the Sun brightens only half of the

Moon’s surface.
▶ The Phases of the Moon

The first quarter phase of the Moon.
If you observe the Moon at night during a month
you will observe that it has different shapes. These 3. Full Moon Phase
shapes of the Moon over a month are called the In the full Moon phase,
Moon’s phases. These are caused by the Moon the face of the Moon can
turning around the Earth. The Moon has four be fully seen. Sun-Earth-
phases: Moon are in a straight
line, with the Earth at the
1. New Moon
middle. The full Moon
2. First Quarter forms fourteen days after
3. Full Moon the new moon.
The appearance of the Moon
4. Last Quarter in the full Moon phase.

As the new moon
changes to the full Moon
phase more of the Moon’s
surface becomes lit up
by the Sun. As the full
Moon changes to the new
Moon, less of the Moon’s
surface is lit up by the
Sun.
The full Moon phase. Crescent
The crescent shape
of the Moon that occurs
4. Last Quarter Phase
between the last quarter
In the last quarter
and the full Moon phase.
phase, the left half of the
Moon can be seen on
Earth. Its shape appears
like a reversed letter ‘ D’.
This phase forms twenty
one days after the new
Moon.
The appearance of the Moon
in the last quarter phase.
For the person on the Earth in the diagram to see

a full Moon, which of the positions 1 to 4 must the
Moon be in?
The last quarter phase of the Moon. A) 1 B) 2 C) 3 D) 4
Phases of the Moon

4
MOTION OF THE EARTH AND THE MOON
FUNNY STORY
THE MOON IN THE WELL
One evening an old man went to a well to get some water. When
he opened the lid of the well, what did he see? The Moon was in
the well.
The frightened man shouted:
“Oh my goodness! The Moon has fallen into the well, quick! bring
a hook and rope!” His wife ran to get a hook and rope and the old
man tied the hook to the rope and threw it in the well. He swung
the rope around and, by chance, it caught on a stone. The old man
pulled it very hard, the rope snapped, the old man fell backwards
onto his back.
When he opened his eyes the first thing he saw was the Moon in the sky. Smiling happily,
the old man said:
– Oooh, thank goodness, it fell in, but I have pulled it out.
PUZZLE
Match the riddles below with the correct picture.
1. Inside burns fire, outside stone beds, on it
1001 heads.
2. A silver plate behind the hill.
3. It heats and burns,
It sleeps in the evening, wakes in the
morning.
DID YOU KNOW?

✔ The shape of the earth and its motion was first calculated by the
scientist Biruni.
✔ When the famous sailor Magellan and his crew started off from
Spain, they sailed always to the west. Magellan died on the
journey, but his crew went on to reach their starting place...

5
Answer the following questions.
1. How many types of motion does the Earth have? Explain.
......................................................................................................................................................
......................................................................................................................................................
2. How many hours does the Earth take to spin around itself? Which events does this cause?
......................................................................................................................................................
......................................................................................................................................................
3. Explain how day and night are formed?
......................................................................................................................................................
......................................................................................................................................................
4. Write down the reason why the Sun is seen at different places during the day.
......................................................................................................................................................
......................................................................................................................................................
5. How long does it take for the Earth to move around the Sun? Which events happen on the Earth during
this motion?
......................................................................................................................................................
......................................................................................................................................................
6. From which natural events were units of time like month, week, and hour formed?
......................................................................................................................................................
......................................................................................................................................................

6
Write T (true) or F (false) in the boxes at the side for the following statements.
True False
1. Sunlight reaches every place on the Earth at the same time.

The places the sunlight reaches on the Earth are in daytime, while the places
2. sunlight cannot reach are at night-time.
3. The Sun appears to move from east to west every day.

The reason the Sun appears at different places during the day is because the
4. Earth spins about itself.
5. The Earth is brightened slowly.

The earth orbits the Sun in 365 days and 6 hours. This period of time is called
6. a year.
7. The Earth is always stopping.
8. The Earth completes a full revolution around the Sun in one week.
9. The Earth completes a full spin about itself in one year.
When the Earth completes a full spin about itself, it causes day and night to be
10. formed.
11. The Moon has only two phases.
7
Match the photographs of the Moon with one of the explanations in the boxes below.
1. 2. 3. 4.
It looks like a In this phase the In this phase the Moon It looks like a reversed
letter ‘D’ to a person on Moon is invisible. It is looks like a plate. The letter
the Earth. between the Sun Earth is between the ‘ D ’ to a person on the
and Earth. Sun and Moon. Earth.

8
Fill in the blanks with the correct words from the list at the side.
1. The Earth is always in a state of ............................. . one day

2. One complete rotation of the Earth about itself is called ..................... . the Sun
the Earth
3. When the Earth has orbited the Sun once, ........................ has passed. motion one year
4. When the Earth spins once about itself ............................ are caused. ay
night and d
5. The Earth both ........................... and orbits ............................ .
spins about itself
6. The Moon orbits ........................... in four weeks.
9
Write down the correct phase of the Moon.

2
1. 4. Which of the following is correct?
A) The Earth’s only motion is spinning.

Moon
B) The Earth is fixed in space and people live
Earth on it.
C) Night and day last for the same amount of
Sun time all over the World.
D) When one side of the Earth faces the Sun,
the other side is at night-time.
Which of the following is incorrect about the
diagram above?
A) The Earth orbits the Sun.

B) The Sun orbits the Earth.
C) The Moon spins about itself.
D) The Moon orbits the Earth.
5. What name is given to one full orbit of the
Moon around the Earth?
A) Year B) Week
2. C) Month D) Day
6. Which of the following phases of the Moon

happens when the dark side of the Moon faces
To be able to see the new moon, which of the Earth, becoming invisible?
positions 1, 2, 3 or 4 should the observer be in? AAA
AAA A) New Moon B) Last quarter
A) 1 B) 2
C) Full Moon D) First quarter
C) 3 D) 4
7. What event causes the formation of night and

day?
3. What name is given to one full orbit of Earth A) The Earth orbits the Sun.
around the Sun? B) The Moon orbits the Sun.
A) Day B) Month C) The Moon orbits Earth.
C) Year D) Season D) The Earth spins about itself.
10
THE EARTH, THE SUN, and THE MOON
W W O R L D M F U L L M O O N
T W A S T R O N A U T F W X P
E A R T H M Y Z S T A R O Q H
L X Y F F U E L T A N K D L A
E S Q S U N A X R O C K E T S
S L D P Y Z R F O Q D Y O J E
C Q X H E A V E N L Y B O D Y
O B S E R V A T O R Y J X M P
P S O R L N E W M O O N J S L
E P S E J O D A Y N I G H T A
M A G E L L A N W Q Z V M V N
Y C W F M O O N F D D T I D E
S E A S O N Z J D A Y Y J W T
SUN OBSERVATORY WORLD SEASON PHASE
EARTH ASTRONAUT DAY PLANET NEW MOON
MOON ASTRONOMY YEAR NIGHT FULL MOON
SPACE ROCKET STAR MAGELLAN
TELESCOPE SPHERE
HEAVENLY
BODY

1. Classification of Living Things
2. The Environment You Live In
CHAPTER 6 | THE WORLD OF LIVING THINGS 105

1. CLASSIFICATION OF
LIVING THINGS
1. How Do You Classify Living Things? When you hear “living things”, you shouldn’t just
think of animals. There are also plants and other
When you go to a market you find the product groups of living things.
you are looking for without too much difficulty. At
the market, products are arranged in an orderly
2. Let’s Classify Plants
way, according to their characteristics, properties,
and the places where they are used. Plants are the most important things for the ex-
istence and continuation of life on Earth. Animals,
people and other groups of living things need oxy-
gen and food to survive. Almost all of the food and
oxygen on the surface of the Earth is produced by
plants.
Plants are spread
over a huge region
At supermarkets, products are placed on the shelves of the surface of the
according to their specific characteristics. Earth. At the same
When books are ar- time, plants also
ranged at libraries, they have some char-
are classified with their acteristics in com-
characteristics. mon. Pines, oaks,
daisies, roses, and
There are a lot of Water lily is a flowering water
wheat are examples
living things on Earth, plant.
of land plants found
both in number and in
in our surroundings;
species. Living things
while water lily and cattails are water plants. On-
have a lot of character-
ions, potatoes, apples, corn, spinach, and rice are
istics that are similar to,
plants that are raised in fields and gardens. You
but also different from,
Books in the library must know more examples for every group of
one another.
are shelved with their plants. At the same time, you may also know some
characteristics in mind. plants in more than one group; flowering plants
and non-flowering plants.
Animals have similar and different characteristics. Non-flowering plant

▶ Examples of Non-Flowering Plants
Non-flowering plants usually live in moist soils
and on the trunks of trees; they don’t have flowers.
The following are examples of non-flowering plants.
Moss
Moss grows on the bark of
the shady side of trees, and
on damp walls and stones.
Flowers are important to many living things.

Moss
Liverwort
This is another type of non-
flowering plant. It is green in
colour. It has a flat structure.
It grows in damp soil and on Flowering plants are
the trees. made up of roots, stems,
leaves, and flowers. When
Liverwort you want to examine the
Horsetail roots, you need to remove
This is a non-flowering the plant from the soil be-
plant with a straight struc- cause the root is the part
ture. Its stem has a cylindri- that usually stays under
cal shape. Horsetail grows in the ground.
fields, stream banks, and on
sloping ground. The parts of a
flowering plant
Horsetail
Ferns
Ferns have roots, stems, ▶ Root
and leaves. However, these
are not true roots and leaves. The root is the part of the plant that is under
Ferns grow in forests, at the the ground. Plant roots can have different shapes
base of trees, in damp places and properties. Some roots are consumed as food.
and on the banks of streams. Carrots are consumed as food.
Above ground, they have
large, green leaves. Ferns
▶ What Parts Does a Flowering Plant Have?

The different colours and smells of plants like
roses, daisies, and carnations beautify our lives.
Flowers are important not only to people, but to
insects and other animals as well. Bees produce a
delicious food from flowers called honey.
The roots of different plants.

▸ Roots hold plants in the ground. ▸ Flowers, leaves and fruit, the above ground
▸ Roots enable the plant to take water and parts of the plant, are supported by the stems.
minerals from the ground. ▸ Stems enable plants to keep upright.
▸ Extra food produced by the plant is stored in
some parts of the plant. The roots of carrots, ▶ Leaf
turnips and sugar beets are rich in nutrients. Leaves are one of the most important parts
These plants’ roots are consumed by people of the plant. Leaves are usually green in colour.
and by animals. They may exhibit many differences in shapes from
one another. For example, corn, sycamore, and
apple leaves are different in appearance from one
another.
Some roots store food. The root holds the

plant in the soil. Various plants’ leaves
▶ Stem
The stem is one of the parts of the plant found Leaves have very
above ground. The structure of the stem can important functions
change from plant to plant. In some plants, the in plants.
stem is soft, thin and green; these are herbaceous
▸ Leaves make
plants. Tomatoes, wheat, sunflowers, and eggplant
food. Plants
are examples of these plants.
produce food
with: water
absorbed The parts of a leaf
from the soil,
carbon dioxide taken from the air, and energy
coming from the Sun. This process is called
photosynthesis.
▸ Leaves are the
respiratory organs
Herbaceous-stemmed plants
of plants. Plants
Some plants’ stems are food release the oxygen
depots. Potatoes are plants that produced during
store nutrients in their stems. the day from the
These are the functions of stems leaves, and take
in plants. in carbon dioxide
as needed. At
▸ Stems transport water and
night, the opposite
minerals from the soil, by the
occurs: oxygen is
roots, to the other parts of
taken in and carbon dioxide is released.
the plant.
▸ Leaves transpire. Plants can’t use all of the
▸ In plants, food is produced
water taken in from the soil. A portion of
in the leaves. Yet the food Poplar, a woody- the water is expelled from the leaves. This
is used in every part of the stemmed plant phenomenon is called transpiration.
plant.

▶ Flower 2. Sepals: These are the green parts which
surround the flower. They protect the flower, espe-
One of the most cially during the budding stage.
important parts of a
plant is the flower. A 3. Male Reproductive Organ (Stamen): These
flower is the part of are the structures that produce pollen. Usually,
the plant which make they are positioned around the female part of the
seeds. These grow into flower.
new plants, once they
have dropped onto the 4. Female Reproductive Organ: This is the
soil. Therefore, flowers seed-producing part of the flower. It’s generally
are the reproductive Seeds are produced in
found in the centre of the flower.
flowers
structures of plants.
Flowers are made up of a number of different 5. Pedicel: This is the part that attaches the flo-
parts. wer to the branch.
3. Let’s Classify Animals

Similarities and differences are also found in
animals. These are used in the classification of
(stamen) animals. Observe the an-
imals living around you.
Examine these charac-
teristics.
▸ How they feed
▸ Where they live
▸ How they reproduce
(carpel)
▸ Body covering Frogs feed on insects.
▸ Does it have a spine.
In the structure of the flower, there are parts with Some of these characteristics are used by
different functions. scientists to classify animals. In addition to these,
there are other characteristics of animals that are
used for classification.
1. Petals: These are the colourful parts of flo-
wers. Petals attract insects to the flower, so they Animals are separated into two main groups:
can carry away pollen. They also give beauty to the vertebrate (with a spine) and invertebrate (without
surroundings. a spine).
Parts of Flowers
You need: Two different flowers, a magnifying glass.

Preparation:
1. Look at the flowers. Identify the male and female parts.
2. Observe the male and female parts of the flowers using a
magnifying glass.

▶ Vertebrates
You know that a skeleton is a structure that spine
enables a person to stand upright and achieve a
shape. One of the main parts of the skeleton is the
spine. The bones that make up your skeleton are
connected to your spine.
Some animals also have a spine in their back.
Animals with a spine are called vertebrates
those without a spine are called invertebrates.
Vertebrates are one of the two basic groups in the
classification of animals. A spine is found in some animals.

Vertebrates are separated into five groups. their offspring breathe with gills, and swim in
the water. Young frogs have a tail. They lose
1. Fish
their tails as they grow older; front and rear
2. Amphibians legs develop to take their place. Their gills
3. Reptiles disappear, and they begin to breathe with lungs
and through their skin. They have long sticky
4. Birds tongues to catch insects.
5. Mammals
1. Fish
▸ They live in water.
▸ Most of their bodies are covered with scales.
▸ They breathe with gills. They take oxygen from
the water, and release the carbon dioxide they
produce into the water.
▸ They move with the help of fins and tail.
▸ They reproduce with eggs.
As a frog larva matures, it loses its tail.
Frog larvae live in water. Once they have become

mature frogs, they continue to live both in water
and on land. Since frogs are a source of food for
many animals, they have many enemies to look out
for.
3. Reptiles
▸ There are species of
reptiles that live on
land, and other species
that live in water.
Fish are vertebrates ▸ Their bodies are
covered with hard
scales.
2. Amphibians
▸ They breathe with Snake
▸ Usually live near lakes, rivers, and streams. lungs.
There are also ▸ They reproduce with eggs.
species that live
in trees and in the ▸ Crocodiles, lizards,
grass. turtles and snakes are
animals in the reptile
▸ Their skin is slimy group.
and moist. ▸ Snakes do not have
▸ They breathe through legs. They move by
their skin and with their Frogs feed on insects. crawling on their
lungs. bellies. They feed on
small animals and on
▸ They feed on insects. Turtle
other animals’ eggs.
▸ Reproduce with eggs. Newly hatched offspring Some species are
are called larvae. After hatching from eggs, poisonous.
▸ There are species of
turtles that live on
land and others that
live in water. Land
turtles feed on plants.
Sea turtles feed on
sea creatures, such
as paddles. Turtles’
bodies are enclosed in Crocodile
a hard shell. Birds’ beaks and claws are Baby birds are looked
useful for catching food. after by their mothers.
▸ Crocodiles live in
rivers and lakes in ▸ Birds breathe with lungs.
hot regions. They live ▸ They reproduce with eggs. young fish and
both in water and amphibians that have hatched from eggs Don’t
on land. They are need their mothers’ care. But young birds need
carnivorous. They feed to be taken care of by their mothers.
Lizard
on mammals, birds,
and fish. They are well-camouflaged in water 5. Mammals
and can swim quickly.
▸ Mammals are also animals that live over a very
▸ There are different species of lizard. The small wide area. They are usually land animals, but
ones usually feed by catching insects with their some species live in seas and oceans.
sticky tongues.
▸ Whales, dolphins and seals are mammals
4. Birds that live in seas and oceans. While these
animals live in water and resemble fish in their
▸ Birds are living things that are distributed appearance, their young are born alive and feed
over a very wide part of the Earth’s surface. on their mother’s milk.
They can live in both cold and hot countries.
Penguins live in the South Pole and parrots live
in the tropics.
▸ Their bodies are covered with feathers. Most
birds can fly with their wings. penguins and
ostriches can’t fly.
Dolphins are mammals.
▸ Mammals’ bodies are covered with hair.

▸ They reproduce by giving birth to live young.
Penguins and ostriches can’t fly. ▸ Mammals, breathe through lungs, whether they
live in the water or not.
▸ The shape and strength of bird’s beaks
vary, depending on their method of feeding. ▸ In appearance, bats resemble birds. However,
Carnivorous birds like eagle and hawks have bats’ bodies are not covered with feathers, but
strong, sharp beaks and claws. Chickens eat with hair. Bats give birth to live young and feed
both meat and plants. Sea birds usually feed them milk. Therefore, bats are in the group of
on fish. flying mammals.

▸ Mammals care
for their offspring.
Newborn offspring
are cared for and
protected by their
mother until they
are old enough to
Omnivores
live on their own.
Bats are flying mammals.
▸ Mammals have
different methods ▶ Invertebrates
of feeding.
Animals like lions, There is no skeleton in the body of an invertebrate.
tigers, hyenas, This means they don’t have a spine, because that
wolves, foxes, is part of the skeleton. Animals that don’t have a
and jackals are spine or a skeleton are called invertebrates.
carnivorous; they Some invertebrate’s bodies have no internal or
are meat eaters external protective, hard structure. Other animals,
(carnivores). The offspring of mammals however, have a hard structure like a shell.
Sheep, cows, are cared for by their
horses, giraffes, mothers for a time.
zebras, deer, and
rabbits are herbivores; they are plant eaters
(herbivores). Some mammals, like bears and
mice eat both meat and plants and are called
omnivores; they are both plant and meat
eaters.
Some invertebrates
carnivores There are species of

invertebrates that live in water,
and others that live on land.
Earthworms, grasshoppers,
butterflies, spiders, bees, flies,
scorpions, snails, and ants are
some of the invertebrates that
live on the land. Earthworms
have a moist, slimy skin Earthworm
structure. They have no legs.
Above ground, they move by crawling, they also
move by tunnelling underground. Butterflies are
also invertebrates. Their colourful appearance
herbivores adds to their beauty.

Animals like flies, Fungi do not make
bees, and ants are their own food. Fungi,
called insects. These like people and animals,
living things have joint- consume food produced
ed legs. Their bodies by other living things.
have a hard covering. Mushrooms: There
are also many kinds of
Butterfly poisonous mushrooms.
Cultivated mushrooms Farmed mushrooms
are those eaten by people.
Cultivated mushrooms
are a kind of fungus.
Cultivated mush-rooms
are grown by people and
are not poisonous. These
mushrooms are both
Bees and grasshoppers are invertebrates. nutritious and tasty. You
The mussel is an invertebrate that lives in water. must not eat unknown
Inside their shell they have a soft body that is made mushrooms you find
Poisonous mushroom
up of two parts. They filter their food from the in fields, gardens, and
water. Jellyfish, sponges, and lobsters are some of forests. If you feel ill when you eat a mushroom,
the invertebrates that live in the sea. you should see a doctor immediately.
Jellyfish Mussels
Vertebrate and invertebrates have differences Mould fungus

in the way they feed and reproduce.
Mould is a kind of
fungus that causes some
4. Fungi types of foods to spoil. If
There are different kinds of fungi, they are bread, cheese, oranges,
mostly found in damp, fertile gardens and forests. lemon, apples, and many
However, fungi are not plants. Fungi have their own other fresh foods have
characteristics; they are a group of living things been left out for a while,
that is completely different from all others. a green or white layer Mouldy cheese is used
forms on them; this layer in the production of
penicillin
is called mould. It forms
more easily on food
that is warm and moist. Yeast is a fungus that is
so small, it can’t be seen. Yeast has a role in the
production of cheeses and in causing air bubbles
to form inside dough. The dough then rises, when
There are major differences between plants and fungi. left covered in a warm place.

Which of the choices below,
about the kind of fungus
shown in the picture, is
incorrect?
A) They are not plants.

B) Some are poisonous.
C) They produce their own
Yeast causes bread dough to rise. food, like plants.
D) They are nutritious.
The Benefits of Fungi 5. Microscopic Living Things

▸ Mushrooms have a high nutritional value. In addition to plants, animals, and fungi, there is
They are eaten as food. another group of living things -- microscopic living
▸ Fungi are used in the production of some things. These are so small, that it is not possible to
cheeses. see them without an instrument. Microscopic living
▸ Fungi are used in baking bread (they cause it things can be observed with a microscope.
to rise).
▸ They are used in the production of some
antibiotics, like penicillin. They are important
in the pharmaceutical industry.
Microscope Microscopic living things

The Dangers of Fungi There are many different kinds of these tiny
▸ Eating poisonous fungi can lead to serious life forms in the soil, air, and water. There are both
illness or even death. harmful and helpful kinds of these tiny life forms,
called micro-organisms or microbes. Helpful micro-
▸ They are the cause of spoilt food.
organisms enable us to make yogurt and cheese
▸ Fungi can cause disease in some from milk, and vinegar from grape juice. Harmful
agricultural products and plants. micro-organisms can cause many illnesses such
as; cholera, dysentery, and tetanus. Microbes can
enter the human body through food, water, air, skin,
or blood.
Fungi can damage agricultural products. Some micro-organisms can cause disease.

1
LET’S CLASSIFY PLANTS
A picture of a flowering plant is given below. Write down the names, characteristics, and functions of
the parts.
Name:
Characteristics and
Functions
Name:
Characteristics and
Functions
Name:
Characteristics and
Functions
Name:
Characteristics and
Functions

2
LET’S CLASSIFY ANIMALS
The photographs of various animals are shown below. Place the letter for each animal A-L, in the
groups they belong to at the bottom of the page.
A B C D
E F G H
I J K L
Mammal Reptile Bird Amphibian Fish
Example: B

3
Write T (true) or F (false) in the spaces given at the beginning of the following statements.
1. (......) Turtles belong to the reptile group.

2. (......) Reptiles reproduce with eggs.
3. (......) Penguins are flying birds.
4. (......) Birds beaks are different, according to how they feed.
5. (......) Whales, dolphins, and seals are marine mammals.
6. (......) Bats are not in the flying mammals group.
7. (......) Bears, mice and chickens eat only meat.
8. (......) Fish get oxygen through their gills.
9. (......) Frogs are vertebrates that live on both land and in the water.
10. (......) Mussels are vertebrates that live in the water.
11. (......) Butterflies and ants don’t have a spine.
12. (......) Crocodiles and birds belong to the group of vertebrates
4
Fill in the blanks in the sentences with correct words from the
list at the side.
1. Animals are separated into two groups: ........................ and eggs bees
.......................... .
lungs
2. Frogs reproduce with ............. . scales
3. Reptiles’ bodies are covered with hard ................. . fins
milk
4. Birds breathe with ................... .
invertebrate
5. Mammals feed their newborn young with ............. . earthworms s
6. Fish move with .............. .
gills
t e b r ates
7. Fish get oxygen through their .............. . ver
frogs snails
8. .................... live both on land and in the water.
9. ................... are invertebrates.
10. ....................... have a moist body and generally live in soil.
11. .................. are animals that move by crawling.

5
Answer the questions below with the names of the living things in the pictures.
1. Which are vertebrates? (...............................................................)

2. Which reproduce by giving birth? (...............................................................)
3. Which take care of their offspring? (...............................................................)
4. Which are in the bird group? (...............................................................)
5. Which breathe through lungs? (...............................................................)
6. Which feed on plants? (...............................................................)
7. Which live both on land and in the water? (...............................................................)
8. Which feed their young with milk? (...............................................................)
9. Which incubate their eggs? (...............................................................)
10. Which are invertebrates? (...............................................................)

6
FUNGI / MICROORGANISMS
Write T (true) or F (false) in the boxes next to the following statements.
True False
Living things that are so small, we can’t see them are called micro-
1.
organisms.
2. Diseases like cholera, and tetanus are caused by micro-organisms.
3. Micro-organisms have no benefits for people.
4. Micro-organisms have no role in making cheese or vinegar.
5. Mushrooms have no leaves or flowers.
6. The fungus that is eaten as food is called a mushroom.
7. Cultivated mushrooms have a very high nutritional value.
8. Yeast is used in baking bread and other baked products.
9. Harmful fungi are the cause of food becoming mouldy.
10. Some kinds of fungi cause a disease that leads to itchy hands and feet.
11. A large number of micro-organisms can be found in a small puddle.
12. Fungi can produce their own food, just like plants.
13. Fungi can multiply more easily in damp places.
14. There are no poisonous mushrooms.

Let’s Classify Plants
1
1. Which of the following is not in the group of 4. Which of the following is useful in making
living things? vinegar?
A) Animals B) Plants A) Micro-organisms

C) Minerals D) Fungi B) Mould
C) Cultivated mushrooms
D) Mushrooms
2. The students below are giving some

information about the classification of living
things. 5.
Which of the students is giving incorrect
information?
A) Classifying living things

makes it easier to study
them.
B) Animals are separated into

two groups: vertebrates
and invertebrates.
C)
Mammals give birth to live
The numbered parts in the picture above are
young and feed them milk.
the different parts of a plant.
Which of the following choices shows the
D) Plants are divided into parts of the plant incorrectly?
three groups: flowering, CCC
non-flowering and fungi A) I - Flower B) II - Fruit
C) III - Stem D) IV - Root
3. Which of the following plants are not grown on 6. Which plant part keeps it upright?
farms? DDD
A) Root B) Flower
A) Cotton B) Water lily
C) Leaf D) Stem
C) Sugar beets D) Barley

1 Let’s Classify Plants
10.
7. A bee is flying around to collect nectar from
flowers. First it lands on the part of the flower
that produces pollen. Then it lands on the part
of the flower that produces seeds.
A flow diagram showing plant classification is

given above.
According to this, which of the following can
be written in spaces I and II?
BBB
I II
A) Non-flowering Liverwort
According to this, which part of the flower did
B) Flowering Horsetail
the bee land on first and second?
CCC C) Flowering Violet
First Second
D) Rooted Plane tree
A) 1 2
B) 3 1
C) 4 3
D) 2 4
11. Plants make food by using water from the soil,
carbon dioxide from the air, and energy from
8. Some plants’ stems are soft, thin, and green. the Sun. This process is called photosynthesis.
These kinds of plants are called ........... plants. As a result of photosynthesis, sugar (food) and
oxygen are formed.
Which of the following terms should be written
in the blank space to complete the sentence In which part of the plant does the process
above? above take place?
BBB AAA
A) woody-stemmed A) Leaf B) Root
B) herbaceous-stemmed C) Flower D) Fruit
C) soft-stemmed
D) thin-stemmed
9. Which of the plants below is in the group of

flowering plants? 12. Which of the following is a desert plant?
BBB CCC
A) Moss B) Lily A) Water lily B) Ivy
C) Fern D) Horsetail C) Cactus D) Moss

Let’s Classify Animals
2
1. I. Seal 4. Which of the following is a flightless bird?
AAA
II. Butterfly
A) Ostrich B) Seagull
III. Snake
C) Swallow D) Crow
Which of the animals above is a reptile?
BBB
A) I only B) III only
C) I and II D) I and III
5. • It lives in water.
• Breathes through gills.
• Usually their bodies are covered with scales.
Which of the following animals have the
2. Some students give some information below characteristics given above?
about animals. DDD
A) Reptiles B) Birds
Which of the students gives incorrect
information? C) Mammals D) Fish
BBB
A)
Animals are divided into two groups:
vertebrates and invertebrates.
B) 6
Frogs give birth to their young and feed
them milk.
C) Lizards, crocodiles, snakes, and turtles

are included in the reptile group.
I II
D)
Birds incubate their eggs and take care
of their offspring.
III IV
Some living things live in the water. They look
like fish. Yet, they are not fish, they belong to
the mammal group.
Which of the animals in the photographs above
3 Which of the animals below is a reptile that is an example of the living things described in
moves by crawling on its belly? the paragraph?
CCC AAA
A) Chameleon B) Turtle A) I only B) II, III and IV
C) Snake D) Earthworm C) I, II and III D) I, III and IV

2 Let’s Classify Animals
7. I. Snail 9.
II. fish
III. Butterfly
Which of the animals in the list above is an
invertebrate?
CCC
A) I and II B) II and III
How many of the animals in the pictures above

are invertebrates?
CCC
A) 1 B) 2
C) 3 D) 4
8.
10. I. The shape and size of birds’ beaks vary,

depending on how they feed.
II. Birds’ bodies are covered with feathers.
Which of the following about the information
given above is correct?
DDD
A) Only I is true.
B) Only II is true.
C) Both are false.
D) Both are true.
Nilgun is working on the Science class
homework project assigned by her teacher.
On her poster she needs to give: the group,
method of feeding, and living place for an
animal.
Which of the following should Nilgun write as 11. Which of the information given below for
answers on her poster? mammals is incorrect?
AAA BBB
A) Mammal - Meat - At the North pole. A) Breathe through lungs.
B) Reptile - Meat - At the North pole. B) Only eat meat.
C) Mammal - Meat - In the forest C) The bat is a flying mammal.
D) Mammal - Plants - In the desert D) Their bodies are covered with hair.

Let’s Meet Fungi and Microscopic Living Things
3
1. Which of the living things below is in a different 4. Which of the following sentences about fungi
group from the others? is incorrect?
CCC CCC
A) Pine B) Daisy A) Fungi don’t have structures like roots and
stems.
C) Fungus D) Grass
B) Fungi can’t produce their own food.
C) Cultivated mushrooms grow naturally in
nature.
D) Some kinds of mushrooms are poisonous.
2. I. Causes food to become mouldy and spoil.

II. Eating the poisonous kinds leads to serious
illness or even death.
III. It is the cause of some plant diseases.
Which of the above are harmful effects of 5. Which of the following tools, given below, is
fungi? used to study microscopic living things?
AAA
DDD
A) I and II B) II and III A) B)
C) D)
3.
I II
Photos of two types of fungi are given above. 6. Which of the following is the reason why yeast
is added to bread before baking it?
Which of the choices below correctly matches BBB
the types of fungi. A) Penicillin, produced by the yeast, kills
DDD
microbes in the dough.
I II
B) Yeast causes the dough to rise and become
A) Mushroom Yeast
spongy, because it releases bubbles of gas
B) Mould Mushroom as it multiplies.
C) Yeast Mould C) Yeast gives flavour to bread.
D) Mushroom Mould D) Yeast prevents baked goods from spoiling.
2. THE ENVIRONMENT
YOU LIVE IN
1. The Habitats of Living Things in The Water plants, like water lilies, live in lakes and
Environment streams. These are also habitats for living things
like frogs, fish, and ducks.
Living things need suitable environmental con-
ditions to continue their lives. Animals like camels, gerbils, scorpions, and liz-
ards that can withstand dry, hot conditions live in
Suitable environmental conditions include: the desert.
▸ their ability to find food and grow Plants also live in different environments. For
▸ protection from animals that hunt them example, cacti can live in the desert, but most
▸ their ability to produce offspring plants cannot stand the dry, hot conditions.
▸ A healthy environment
The places where animals live are called their
habitats. The size and characteristics of habitats vary.
There are a lot of habitats around you. For
example, birds make nests in the branches of trees
in your environment, they find shelter, lay eggs,
raise their young and feed there.
Camels live in the desert.
2. How Living Things Feed

Living things need energy to continue living.
Plants carry out photo-
synthesis and produce
their own food. Some an-
imals feed on plants, oth-
ers feed on other animals.
All living things except
plants, meet their energy
Birds’ habitat needs by feeding on oth-
er living things, which in
For a small living turn feed on others. This
thing, like a worm, the forms a chain relation-
space under a rock is ship between them, called Some animals are plant
eaters.
a habitat. For a lion, a the food chain.
forest is a habitat.
Forests are habitats
for many very different
kinds of living things.
Tropical forests, are Forests are large habitats.
places where the
greatest variety of living things exist. Some animals are meat eaters.

Plants are found on the first 3. People and the Environment
step of the food chain.
Living things that feed on Every living thing has a habitat and meets its
plants have their place needs from that environment. Habitats are made
on the second step of up of different living and non-living things. Humans
the food chain. Living and the other living things in the environment have
things that eat meat a relationship and affect each other continuously.
are the third step of the
food chain.
All living things in the food chain
have a role to play. The absence of one of these
living things breaks the food chain; destroying the
balance of nature. Every living thing plays a role in
nature.
A land habitat A sea habitat

food chain food chain
Living and non-living things make up the environment.
Humans change the environment in which they

live. The environment is affected by human activi-
ties. An environment that isn’t used well, becomes
polluted.
Humans change the environment in which they live.
Environmental pollution includes air, water, and

soil pollution. Poisonous gases coming out of
homes workplaces, factory smokestacks, and car
exhausts pollute the air. Respiratory diseases may
develop in people who breathe this polluted air.

Trees from forests are used to make writing
paper. Wasting paper and not using both sides of
the paper causes more trees to be cut.
Forests are:
▸ the source of the world’s oxygen.
▸ the habitat of many living things.
▸ living things that prevent erosion.
Poisonous gases from factory smokestacks pollute the air.

▸ living things with economic value.
Filters should be placed Forests, which are so important to all living

on factory smokestacks and things, should not be destroyed. Behaviour that
industrial buildings should be could start forest fires should be avoided. One
built outside cities to prevent careless act could destroy a forest that will need
air pollution. High quality fu- decades to grow back again.
els, that don’t release poison-
ous gases, should be used in
homes and vehicles.
Detergents, used in homes and sewer water,
mix with water sources to pollute the water. Poi-
sonous gases found in the air are carried to the
ground in rainwater, and mix with water on the
Earth’s surface. These are two different ways that
water can be polluted. Living things can’t survive
in polluted streams and lakes. Humans who use
polluted water catch diseases like cholera. To pre-
vent water pollution, water should not be wasted.
The tap should not be left running when brushing
your teeth or washing your hands; it should only be
turned on when needed.
The soil is often polluted with paper, plastic bot-
tles, plastic bags, and tin cans. These will contin- You know that human activities damage air,
ue to pollute the soil for hundreds of years without water, and soil. Humans also do harm to plants
decaying. People must be aware that rubbish they and animals. Humans often destroy environments,
drop in the environment will continue to pollute the causing animals to die. Hunting is the main cause
soil for centuries. Other sources of soil pollution for the decrease in numbers of many kinds of
are poisonous gases in the air and some fertilisers.
animals; this has even caused the extinction of
many species of animals.
Some waste doesn’t decompose for a long time, this Excessive hunting has left some animals in danger of
pollutes the soil. facing extinction.

7
YOUR ENVIRONMENT
Three examples of land and water food chains are given below. However, there is an empty space where
a living thing should go in some links of the chains. Write an appropriate living thing in each empty space
of the chains.

8
YOUR ENVIRONMENT
Write T (true) or F (false) in the boxes at the side for the following statements.
True False
1. All habitats have the same climate, feeding, and living conditions.
High quality fuels, that don’t release poisonous gases, should be used
2.
to prevent air pollution.
3. The polar bear is an animal that can live in a hot climate.
4. Environmental pollution could be a cause of death for animals.
5. The forest is a bigger habitat than a schoolyard.
Waste from a factory, should be treated to make it harmless before it is

6.
released into the environment. This decreases water pollution.
7. Air, soil, and water are non-living things that make up the environment.
8. Plants meet their need for food by carrying out photosynthesis.
In a food chain, every link is a different living thing. One living thing is
9.
another living thing’s food.
10. Not every living thing has a place and a role in nature.
Its alright to throw away things like paper and banana skins on the
11.
ground.
12. Plastic and nylon bags thrown onto the soil Don’t cause lasting pollution.
13. Forests are the source of the oxygen you need to live.

4
1. Which of the living things, given below, is not 4. Which of the living things below feeds on both
matched with its habitat? meat and plants?
A) Camel - Desert A) Bison B) Crocodile

B) Bear - Zoo C) Bear D) Hawk
C) Lion - African plains
D) Squirrel - Forest
5. I. Air
2. Which of the living things, shown below, is not
II. Micro-organisms
the last link in a food chain made up of three
links? III. Water
Which of the above, found in the environment
A) B) is not a living thing?
AAA
A) II only B) I and II
C) II and III D) I and III
C) D)
6. Which of the following animals› natural habitat
is not the polar region?
BBB
A) B)
3.
A food chain is shown in the figure above.

C) D)
Which of the living things below goes into the
empty link in this food chain?
A) B)
7. Plant Rabbit ?
C) D) Which of the following should be in the food
chain above in the place marked with “?” ?
AAA
A) Fox B) Mouse
C) Sheep D) Gazelle

4
8. 11. The numbers of one kind of living thing in a
region has decreased.
Which of the following cannot have happened
in that region?
BBB
A) An increase in forest fires
B) A decrease in environmental pollution
C) A decrease in water sources
D) A decrease in food sources
Three of the four living things, shown above,

make up a food chain. Which of the living 12.
things is not in this food chain?
CCC
A) Owl B) Grain
C) Dolphin D) Mouse
9. Living things eat different types of food.

Which of the animals below is not correctly
matched with the food it eats? Which of the following is polluted first by the
DDD factory given above?
Animal Food CCC
A) Space B) Water
A) Squirrel Walnut
C) Air D) Soil
B) Rabbit Carrot
C) Frog Insect
D) Grasshopper Snake
13. Which of the following sentences about forests

is incorrect?
CCC
10. Which of the following is not a natural habitat A) They are the source of the world’s oxygen.
for living things? B) They are the source of food for living things.
DDD
A) River B) Sea C) They limit the habitats of living things.
C) Desert D) Zoo D) They keep the soil from eroding.

9
LET’S LOOK AROUND AND GET TO KNOW THE WORLD OF LIVING THINGS
Fill in the spaces below.
1 2 3
Life group : ............................. Life group : ............................. Life group : .............................

How does it feed? : ................. How does it feed? : ................. How does it feed? : .................
Where does it live? : ................ Where does it live? : ................ Where does it live? : ................
How does it reproduce? : .......... How does it reproduce? : .......... How does it reproduce? : ..........
4 5 6

7 8 9


10
LET’S LOOK AROUND AND GET TO KNOW THE WORLD OF LIVING THINGS
M I C R O S C O P I C U M V F
V A I N V E R T E B R A T E O
F I S H I P L A N T I Z M G O
A A N I M A L K X L N U K G D
V E R T E B R A T E S E T L C
F L O W E R V W A G E L F H H
U K M X A R U L A Y C Z R M A
C L A S S I F I C A T I O N I
B I R D T T P Y Y H X R G S N
K Z I R E A R T H W O R M E W
I N M M U S H R O O M P V P E
E N V I R O N M E N T U N A E
K K M W I Y N F O R E S T L B
L V L E Z T I Y R E P T I L E
H O R S E T A I L E A T T K E
CLASSIFICATION INSECT INVERTEBRATE FROG FOREST
ANIMAL SEPAL
MICROSCOPIC BIRD EARTHWORM
ENVIRONMENT EGG
REPTILE PLANT MUSHROOM
FISH BEE
VERTEBRATE HORSETAIL FLOWER FOOD CHAIN EAT

1. Light
2. Sound
CHAPTER 7 | LIGHT AND SOUND 135

1. LIGHT
1. How Does Light Spread Out?
To be able to see the things around you, you

need light. Light comes from either natural or man
made (artificial) sources. There are many kinds of
light sources with different properties.
A natural light source man-made light source
Some objects produce their own light. These

objects are called natural light sources; the Sun Light observed through straight and curved straws
is a natural light source. Man-made light sources
are called artificial light sources; a candle is an Light rays come from all directions on the light
artificial light source. source. This can be seen in the diagram of the
You have seen sunlight in foggy weather, torch- candle below. Light rays are shown as lines with
light in the night, or a car’s headlamps at night-time. arrows in diagrams. The arrows show the direction
The light appears as bright stripes that spread out- of travel of the rays.
wards and get further apart. This shows that light
travels in straight lines.
Light spreads out in straight lines.
If you look at a candle flame with a straight

straw you can see the candle’s flame. However,
if you look at the candle through a curved straw
you won’t see it. This experiment shows that light Light travels outwards in straight lines from all
travels in straight lines. directions of a light source

Observing How Light Travels
You need: A candle, three pieces of cardboard (size 10x10 cm),

a nail, three match boxes, and some thumbtacks.
Preparation:
1. Make small holes exactly in the middle of each piece of card
with a nail.
2. Fix the cards to the match boxes with thumbtacks. Set up the
materials as shown in the diagram.
3. Light the candle and arrange the cards so that you can see the candlelight through the holes.
4. Now, move the card in the middle to the right or left. Do you see the light from the candle? Explain
your observations?
When light rays travel outwards from a source, Light cannot travel through walls, wood, metal,
and there are no objects in the way, it spreads out and stone. These are called opaque substances.
in all directions. If the light source is placed inside When light falls onto some substances only part
a closed, black box, no light will be seen. However, of it can travel through them. For example; frost-
if you make pinholes anywhere in the box, light rays ed glass, clouds, fog, and very thin/tracing paper.
will spread out in straight lines from all directions. These are called translucent substances.
A diagram of a light ray is always a straight
line, showing the direction it is travelling in. Light
can only travel in a certain direction if there are no
objects in the way to stop it.
2. What Happens When Light Falls onto an

Object?
Light cannot travel through all substances.
transparent translucent opaque
The substances which allow light to pass through
are called transparent substances. For example,
light can travel through thin plastic and glass. Different amounts of light pass through each material.
Greenhouses are covered with plastic or glass so
that light can enter. The thickness of a material can change its trans-
parency.
Water is a transparent substance; if you are on
a boat near the sea shore and the sea is clear, you
can see fish below the surface and even the sea
floor below them. But if you go into deeper water
and look downwards, it will be more difficult to see
the sea floor clearly. This is because light cannot
travel through such a thick layer of water. It has
Greenhouses are covered with plastic or glass. become opaque.

On a cloudy day or in the fog, the surroundings
are not well lit, and you cannot see as far as on
a clear day. This is because the clouds or fog are
translucent.
Fog stops part of the light that falls onto it.

The size of an object affects the size of its shadow.
Observing your sur-
roundings helps you de- To make a shadow, an opaque object and a
cide which objects are light source are needed. Light rays that fall on the
transparent, translucent, object cannot travel through. This can be seen as
or opaque. For example, darkness on the screen. Complete darkness means
you can see that people no light is there. This is the shadow.
are opaque. However,
most light is invisible to
your eyes. This light can
pass through objects X-rays can travel through
that appear opaque to the softer parts of the
your eyes. However, the human body.
objects are transparent
to X-rays. An example of this type of invisible light
are X-rays. They are used in medicine and technol-
ogy to see into opaque objects.

Which of the following is a transparent substance?
A) Frosted glass B) Wood

C) Air D) Brick
3. Shadows

When you walk on the street on a sunny day,

something follows you. This dark shape follows
you everywhere, it is your shadow.
Light rays travel to an object. Some of them fall upon
If an object is big, its shadow is big. If the object the object to cause a shadow.
is small, it has a small shadow.
If the distance between the light source, object,
and screen is changed it affects the size of the
shadow.
1. When moving the light source away from the
object, the shadow on the screen gets smaller.

Umbra and penumbra
4. Sun and Shadows
2. When moving the object towards the light

source, the shadow on the screen gets bigger.

The Sun changes its place in the sky during the daytime
3. When moving the screen towards the object, The position of the Sun in the sky is always
the shadow on the screen gets smaller. moving. As the Sun changes position in the sky, it
also makes shadows on the ground move.
On a clear sunny day, if you fix a rod into the

ground and watch it all day, you will notice that the

length and position of its shadow changes over

the day. From dawn to noon the shadow of the

rod grows shorter and from noon to dusk it grows
longer.
Light rays that come from two different sources The changing position
cause differences in the shadow they produce. The and length of shadows can
experiment below shows two light sources falling be used to make a special
onto the same object. Two shadows appear on the type of clock called a
screen. The areas where the two shadows are on sundial. This helps people
top of each other is darker and is called the umbra. tell the time of day, but it
The rest of the shadow is not as dark and is called can only be used outside in
the penumbra. the sunlight.

5. Eclipses of the Sun and the Moon
▶ Eclipse of the Sun
An eclipse of the Sun is caused by the shadow
of the Moon on the Earth The Moon orbits Earth,
which orbits the Sun. During this motion, the Moon
gets between the Sun and Earth.
Lunar Eclipse
You can only see a

lunar eclipse at night
time.
Whenever the Earth,
Sun, and Moon lie
along a straight line,

one of these eclipses
occurs.

Solar eclipse Model of a lunar eclipse
At this time the

Moon’s shadow falls
onto some part of the
Earth
Earth’s surface. The Sun
Sun cannot be seen by
people in areas where Moon
this shadow falls. This
is usually called a so- Sun
Earth
lar eclipse.
Moon
Model of a solar eclipse
In a solar eclipse the In a lunar eclipse the
Moon is nearer the Sun Earth is nearer the Sun
than the Earth is. than the Moon is.
▶ Eclipse of the Moon
As the Moon orbits the Earth, it travels to the
side of the Earth facing away from the Sun. This
time the Earth is between the Sun and the Moon.
The shadow of the Earth falls onto the Moon, which In which natural event does the shadow of the
doesn’t get any sunlight. This means the Moon Moon fall onto the Earth?
cannot reflect light from the Sun, so it cannot be
A) Solar eclipse B) Lunar eclipse
seen. This is an eclipse of the Moon, which is usu-
ally called a lunar eclipse. C) Eclipse of a star D) Eclipse of the Earth

How are Eclipses Formed?
You need: A light source (i.e. a torch), a big ball and a small ball.
Preparation:
1. Imagine that the light source represents the Sun, the big ball represents the Earth and the small ball
represents the Moon.
2. Place them as shown in figure I. Turn on the light. Which ball is in the shadow?
3. Now, arrange them as shown in figure II. Where does shadow form on the ‘Earth’?
1
LIGHT
A school pupil builds an experiment to observe shadows. She

places an object between a light source and a screen, so that the
shadow of the object falls onto the screen.
Answer the following questions about this experiment.
1. How does the size of the shadow change when the light source
is moved towards the object?
......................................................................................................................................................
2. How does the size of the shadow change when the screen is moved away from the object?
......................................................................................................................................................
3. What must be done to increase the size of the shadow if the screen is fixed in position?
......................................................................................................................................................
......................................................................................................................................................
4. If you want to cause more than one shadow on the screen what must you do?
......................................................................................................................................................
5. How does changing the size of an object and its shape affect its shadow?
......................................................................................................................................................

2
LIGHT
opaque sundial umbra smaller
solar eclipse straight lines light rays
1. The light from a source travels in all directions as ............................ .
2. A ............................ is an instrument that uses the change in position and length of an object’s
shadow to measure time.
3. ............................ are the lines that show the direction of travel of light outwards from a source.
4. When an object is moved away from a light source its shadow gets ............................ .
5. If light comes out from a pinhole it forms an ............................ behind an object in its way.
6. A substance through which light cannot travel is called an ............................ substance.
7. When the Moon moves between the Sun and Earth a ............................ is caused.
3
LIGHT
If the sentences below are correct place a  and if they are incorrect place a .
 1. During a lunar eclipse, the Earth is nearer the Sun than the Moon.
 2. Light cannot pass through substances that are opaque.
 3. During eclipses of the Sun or Moon, all the surface of the Earth is visible.
 4. At noon, when the Sun is high in the sky, shadows are shortest.
 5. Glass, air, and water are examples of translucent substances.
 6. When a light source is brought near to an object, the size of its shadow
grows.

4
LIGHT

W O R D
H U N T
S O L A R E C L I P S E W X E
F U M B R A X Y D W Z L P L A
L U N A R E C L I P S E E P R
Y R A Y W L Z Y X M O O N L T
T R A N S P A R E N T M U A H
L X O F W O P A Q U E L M N M
S T R A I G H T L I N E B E W
W Z Y S U N S H A D O W R T H
L I G H T S O U R C E Y A L X
LIGHT SOURCE UMBRA TRANSPARENT

STRAIGHT LINE PENUMBRA OPAQUE
LUNAR ECLIPSE PLANET SUN

SOLAR ECLIPSE EARTH RAY
SHADOW MOON

5
LIGHT
Write down answers to the questions below.
What is light?
..................................................................................
..................................................................................
..................................................................................
..................................................................................
If there were no light sources,

what changes would there be in Explain the meaning of
your life? transparent and opaque.
............................................... ...............................................
............................................... ...............................................
............................................... ...............................................
...............................................
How does light make your life How does light travel? What
easier? happens when light falls on an
object?
...............................................
...............................................
...............................................
...............................................
...............................................
...............................................
...............................................
What can you do using light?

..................................................................................
..................................................................................
..................................................................................
..................................................................................

1
1. Which of the objects below doesn’t form an 4. Mustafa wants to show that light travels
umbra? in straight lines, so he carries out the three
activities below:
A) B)
I. He holds two sheets of cardboard parallel
to each other and makes a pinhole through
each of them. Next to these he holds a
torch.
II. He places a light source inside a black
box and closes it. He then makes pinholes
C) D) through the box.
III. He holds a torch next to a volleyball and
makes a shadow on the board.
Which of his experiments shows light travels
in straight lines?
A) I only B) II only
C) I and II D) I, II and III
2. In which of the mediums below can’t light

travel?
AAA
A) Rock B) Air
C) Space D) Glass
5. I. Thin objects
II. Opaque objects
III. Transparent objects
IV. Thick objects
Which of the objects above does light always
travel through?
3. AAA
A) III only B) II and IV
C) I and III D) I, II and IV

How can the shadow in this experiment be

made smaller?
A) Bring the object nearer the light source.

B) Bring the light source nearer the object.
6. Which of the objects below is opaque?
C) Take the screen further away from the
object. A) Air B) Notebook
D) Bring the object nearer the screen. C) Tea glass D) Glass window

1
7. 9. The four school pupils below tell you something
they know about light.
Which of the pupils is incorrect?
AAA
A)
Light is a type of
substance.
B) The shape of an object

affects its shadow. A
shadow looks like its object.
The picture shows the position of the Sun at C) Some objects produce
three different times of a day. The shadow of light, which then travels
the child changes all the day, so at each posi- away from it as rays. These
tion I, II and III his shadow has a different size. types of objects are called
Place the positions of the Sun in order, from natural light sources.
the position that causes the smallest sized
shadow of the child, to the position that D)
causes the largest sized shadow of the child. Light rays travel in all
CCC directions in straight lines.
A) I, II, III B) II, I, III
C) III, II, I D) III, I, II
8. Which of the choices below about the forma-

tion of shadows is correct?
BBB
A) Light forms shadows behind substances 10. Which of the choices below are the correct
through which it travels. orders of the Earth, Sun, and Moon during a
B) Light forms shadows behind opaque solar eclipse?
substances. CCC
A) Earth - Sun - Moon
C) When an opaque object is moved away
from a light source its shadow gets bigger. B) Sun - Earth - Moon
D) When an opaque object is moved towards a C) Sun - Moon - Earth

light source its shadow gets smaller. D) Moon - Earth - Sun

2. SOUND
1. Formation and Movement of Sound Sound waves, using air as a medium, cause
waves of sound which travel in all directions.
We hear sounds These waves spread forwards because vibrating
using our ears. When particles of the medium hit or strike particles in
an object moves front of them, making them vibrate. These particles
backwards and for- then strike those in front of them; this is how the
wards it vibrates. Newton’s cradle in the photograph works.
When an object vi-
brates, the air around
the object also vi-
brates. Vibrating air
produces sounds
which move in air, and
reach your ears. This
means that sound
travels in air in the form of waves, just like waves in
water; sound is a kind of energy.
Look at the picture below. How do water

waves move?
Natural sound sources

People, birds, bees, ducks and frogs are all
The spreading out of a sound wave from its source is living sound sources; they are also natural sound
like the spreading out of a water wave from its source. sources. There are also non-living natural sound
sources, such as the wind, thunder, and rain.
Every substance or object that makes a sound is Examples of man-made sound sources are: the
a sound source. Bees and mosquitoes make sound drums, flutes, music stereos, and machines. These
by vibrating their wings. only work when people use them.
To make sound two
things are needed; vi-
bration and a medium
through which it can
travel.
Mosquitoes cause sound by

vibrating their wings. Man-made sound sources

Sound sources can spread out and travel in
solid, liquid, or gas mediums to your ears. You can
hear the sound sources below:
▸ a telephone ringing on the table
▸ an alarm clock ringing
▸ programmes on the car radio
All these devices need air as their medium.
Sound travels in solid mediums
Sound travels fastest

through solids. This is because
particles in a solid are much
closer together than those in
a liquid or gas, allowing sound
waves to travel more quickly
Sound that travels in a gas medium through it.
Sound needs a medium to travel through. Sound

Sound also travels through liquid mediums. cannot travel through empty space. If an alarm
When you dive under water, you hear some sounds. clock is placed inside a vessel and all the air is
If you bang two stones together underwater, you taken out, you won’t hear the sound of the alarm
can hear their noise. Some underwater animals, from the clock.
like dolphins and whales, talk to each other by
making sounds under water. Since there is no air inside the vessel, there
will be no sound wave. There are no particles in
space to pass on the sound energy, so there are no
vibrations. Space is silent.
Sound can travel in liquid mediums
Sound can also travel in solids. You hear sounds

from outside your house all the time. Rain, thunder,
wind, people talking, and cars driving past. This
means the sound waves have travelled through
walls, doors and windows; which are solid. Also, if
you place your ear close to a table and gently tap it
with your fingers, you will hear the sound which has
travelled through the solid table to your ears. Sound cannot travel in space.

2. How Does Sound Spread Out in Each 3. Can You Stop Sound Spreading Out?
Medium?
The same event causes different sounds in A sound insulator
each medium. Different types of materials make is a substance that
different sounds. For example, ladies high heeled stops sound travel-
shoes make different sounds on wood floors to ling in a certain direc-
that they make on stone floors. tion. Sound insulators
protect people from
the harmful effects
of noise. This is very
important in buildings
such as libraries, cin- Sound insulation is very
emas, sound studios, important in sound studios.
and concert halls.
▶ Sounds and Their Mediums

When sound is spreading out in a medium and
it falls upon an object, some of it is reflected, some
of it is absorbed by the object, and the rest travels
through to the other side.
Different types of materials make different sounds.
Different objects, tea cups, plastic cups, water

glasses, and metal cups also produce different
sounds. For example, if you struck each of these
objects with a metal spoon, you may be able to
guess which object it was.
Sound falls upon an object
Sound from the same source behaves differently

when it falls upon different objects.
Some materials are better at decreasing the
The material an object is made of affects the amount of sound. Cotton wool and foam decrease
sound it makes. noise because they have a lot of empty spaces
inside their structures. Sound cannot travel through
empty space, because there are a lot less particles
Substances behave differently when sound and
to pass on the energy.
light are incident on them. Sound cannot travel
through empty space, but light can. Light cannot Some solids can be covered in sound insulation
travel through opaque objects, but sound can; materials, to reduce the amount of sound passing
sound can travel through all solids. through them.

You need: A wooden box, a glass case, a plastic bag or cardboard box.
Preparation:
1. Place a cell phone inside a wooden box and let it ring. Listen to the sound it makes.
2. Now place the cell phone inside a plastic bag and let it ring. Listen to the sound it makes carefully.
3. Now fill the plastic bag with cotton wool, foam and other soft materials that you think may help.
Place the bag, materials, and cell phone inside a cardboard box. Let the cell phone ring. Listen to
the sound it makes.
cell phone
You will notice that the more material you place in the plastic bag, the quieter the sound the cell phone
makes.
▶ Sound and Mediums

In some buildings, sound insulation is very Sound that makes
important. people uncomfortable is
called noise. There is a
lot of noise in big cities.
In big cities, people live
in blocks of flats. A lot of
noise is caused here by
people using household Busy roads and centres
appliances like: TV’s, vac- are noisy places.
uum cleaners, washing
machines, and music ste-
reos. The sounds all travel through walls and doors
into the flats around them, causing noise and mak-
ing people uncomfortable.
The sounds from traffic outside also travels
through windows and doors to make people
Good sound insulation is needed in TV studios so that
uncomfortable. Some work places and schools
noise from outside cannot be heard. also make a lot of noise and make people
uncomfortable.

Buildings must be insulated from noise pollu- ▶ Sound and Health
tion. Technology helps by making sound insulating
materials. As time goes by, the amount of noise in the
surroundings increases, since more technology
Technology uses the fact that sound cannot products are being produced. This noise affects
travel through empty space. people badly:
Double glazed windows reduce sound, because
there is empty space between two plane windows. Effects of noise:
▸ Ioss of hearing for short times
▸ increase in blood pressure, faster breathing,
increasing pulse
▸ behaviour problems, being nervous and
stressed
▸ doing less work, difficulty in thinking, working
more slowly
If people are forced to listen to loud noise for a

long time, they lose their hearing. This will cause
problems at work, since they cannot hear other
Sound insulation materials are used for buildings. people trying to warn them of danger. It will also
cause work accidents.
There are other ways to decrease the amount People at noisy workplaces must wear earmuffs
of noise: to protect their ears from hearing loss. Young
▸ build homes away from airports and factories. people must also be careful not to turn up the
volume on their music stereos or go to concerts
▸ stop people in vehicles from using their horns
where loud music is being played.
too much on the streets.
▸ wear protective ear covers in noisy work
places.
▸ cover buildings with sound insulating
materials.
▸ keep the volume of TV’s, radios, and music
stereos down.
Airports must be made outside city centres, away from living areas.

6
SOUND
Write down the answers to the questions below.
Write down the names of Which animal sound do you How can you communicate
the musical instruments that like best? with a deaf person?
you think have the nicest ............................................ ............................................
sounds.
............................................ ............................................
............................................
............................................ ............................................
............................................
............................................ ............................................
............................................
............................................ ............................................
............................................
Does sound make people uncomfortable?

Why?
............................................................................
............................................................................
............................................................................
............................................................................
7
SOUND
Write down the answers to the questions below.
1. If you see a friend on the street, what do you do to get her to notice you?
......................................................................................................................................................
2. place your ear on your desk, now tap your desk with your fingernails and listen to the sound. Now take
your ear away from your desk, and keep tapping your desk with your fingernails. do you hear better
when your ear is on the desk or off it? Why?
......................................................................................................................................................
3. Bang two stones together inside a container filled with water. listen to the sound with your ear near
the container and further away from it. Do you hear better when your ear is near the container or
further away from it? Why?
......................................................................................................................................................

8
SOUND
Some properties of light and sound are given below. Place an ‘X’ in the list when you think the description
best fits ‘Light’ or ‘Sound’. If you think it fits both place ‘X’ in both lists.
LIGHT SOUND
1. It is formed when matter vibrates. ................... ...................
2. It can be formed by different sources. ................... ...................
3. It spreads out in straight lines in all directions. ................... ...................
4. It moves differently in different substances. ................... ...................
5. It can travel through non-transparent mediums. ................... ...................
6. Its a type of energy. ................... ...................
7. It helps you hear. ................... ...................
8. It helps you see. ................... ...................
9. It can travel through transparent mediums. ................... ...................
10. Insulation can be made to stop it travelling. ................... ...................
9
SOUND
Tick (√) True or False for the following statements.
True False
1. Sound can travel through empty space.
2. Sound travels faster through solids.
You can hear sounds travelling through solid objects better if you put your ear on
3.
them.
4. Sound insulation can be made using materials like foam, sponge and wool.
5. Sound can cause pollution.
6. Light is a kind of energy.
7. Light travels in curved lines.

10
SOUND
Match the following pictures with the note describing them.
Liquids are one of the

mediums in which sound
can travel.
It is a device that is used to

make sound louder.
Sound doesn’t travel through

space.
This is an instrument used to

record light and sound.
Sound spreads out

as waves.
An event that shows

light travels in straight
lines.

11
SOUND

W O R D
H U N T
N O I S E L A T Y W S P A C E
U Q K O Q U I B R A T I O N M
E Y M U S I C K S J C P Q C E
K E K N G R A M O P H O N E D
B A Y D Z J U S N S A D U F I
A R L W A X J L A J Q S B A U
T U V I D E O K R E W L U K M
E W Z Q I N S U L A T I O N A
SOUND MUSIC MEDIUM

NOISE SPACE VIBRATION
BAT EAR IPOD

INSULATION VIDEO GRAMOPHONE
SONAR

12
SOUND
Place the words below into the correct places in the diagram.
Liquid medium Sound pollution stops Space Sound volume
when there is ........................................ decreases

too much
Sound
insulation
can cause
can change Technology

..................................
a property
can be used
can
Sound Recording
store
..........................
is related to Sound spreads out
can be can be can be cannot be
Solid medium Gas medium

............................. .............................

2
1. Which of the following is not a sound source? 4. In which of the following mediums can’t sound
travel?
A) Radio B) Desk
C) Bird D) Mobile phone A) Solid B) liquid
C) Gas D) Space
2. I. If people working in noisy workplaces wear 5. I. A substance

ear muffs they can protect their hearing. II. A type of energy
II. To build the sound systems for cinemas, III. It spreads out in liquids
theatres, concerts, and conference halls, IV. It travels through space
engineers are needed.
Which of the above information about sound
Which of the choices describe the two sen- is correct?
tences I and II above?
CCC CCC
A) Only I is true A) II only B) II and IV
B) Only II is true C) II and III D) I, II, III and IV
C) Both are correct
D) Both are incorrect
6. With improving technology, more devices and

machines are being made; which causes more
noise. This has several bad effects on people.
3. Which of the devices used to listen to sound Which of the sound sources below does not
below is the latest technology device? cause noise?
A) B) A) B)
C) D) C) D)

2
7. There is too much noise coming into a man’s 10.
house from outside, he wants to install sound
insulation in his house.
Which of the changes below won’t be good
insulation for his house?
DDD
A) Fixing double glazed windows in his home
B) Placing foam around his window frames
C) Covering his roof with wool and felt
D) Placing coloured glass windows in his house,
Three different devices are shown that produce
instead of transparent glass windows
or record sound.
Which is the correct order of the devices from
oldest technology to latest technology?
CCC
A) I, III, II B) II, III, I
C) III, II, I D) II, I, III
8. I. Using double glazed windows
II. Placing anti-knock beads in the exhaust
III. Manufacturing household devices, like
vacuum cleaners and washing machines,
which work more quietly.
Which of the activities above will decrease
noise pollution?
DDD
A) I only B) II only
9. • Behaviour problems, nervousness, and stress

• Not able to do much work, unable to con-
centrate, slower movement
• Deaf or loss of hearing for a short while
11. How can the noise from everyday household
All the problems above occur in a factory. machines be reduced?
What could be the reason for them?
BBB A) Insulate all buildings with sound insulation.
A) The factory is too large
B) Make sure all machines have sound insula-
B) The surroundings are very noisy tion around them.
C) Using ear muffs when working C) Try using ear muffs in the house.
D) Walking backwards and forwards to work D) Leave the house when they are working.

13
LIGHT AND SOUND
Did you know? Did you know?

Did you know that only a small Did you know that if you place a
amount of electric energy is microphone near a cicada the measured
changed to light by a normal sound volume will be 158 decibels. This
light bulb; the rest is changed is the same value as a grenade. The
into heat. In a natural light source, insect’s ears are designed so that they are
like a firefly, almost 100% of its protected inside a capsule. This design
energy is changed into light. protects its ears from hearing loss.
Did you know? Did you know?

▸ A penguin chick can tell who its ▸ Cuttlefish living near ocean beds
mother is in a crowd of thousands of communicate by scattering light from
penguins, by the sound of their skins in patterns.
her voice. ▸ When only a small amount of light
▸ Night hunting owls can reaches your iris it grows larger, if
fly silently at night, large amounts of light reach your iris it
because their soft fur grows smaller. This means it controls
is designed to trap how much light gets into your eyes.
empty space inside. ▸ It takes 8 minutes for the Sun’s rays
Sound cannot travel to reach Earth and 1.28 seconds for
well through empty light reflected from the Moon to reach
space, so the sound Earth.
is decreased.
▸ Bats can’t see
insects
on the
ground, but
they can hear them when
they fly off the ground into the air.

14
LIGHT AND SOUND
1. The Sun and fireflies are ............................ light sources.
2. The light leaving a source will travel in ............................ if they don’t fall on an object.
3. When a non-transparent object is placed in front of light rays, the light ............................ through.
4. The part of a screen that is totally dark is called an ............................ .
5. Sound doesn’t travel through ............................ .
6. At noon, shadows are ............................ . cannot travel

umbra
7. Light travels in ............................ . ns
all directio natural
8. To be heard from a long distance away, a person
e short
speaking uses a device called a ............................ .
megaphon
9. When the Moon is caught between the Sun and space faster
Earth a ............................ occurs.
straig
ht line
10. When the Earth is caught between the Sun and lunar eclip s
se
Moon a ............................ occurs.
e
solar eclips
11. Sound travels ............................ in solids than in air.

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PRIMARY

Global Bridge Publishing is a part of Global Education.

All Rights Reserved. No part of this book may be reproduced or utilized

How To Study Science?

4. Substances That Are Harmful to Your Health . . . . . . . . . . . . . . . . . . . . 33

Chapter 2 THE STATES OF MATTER

2. The Changing States of Water in Nature . . . . . . . . . . . . . . . . . . . . . . . 52

Chapter 3 FORCE AND MOTION

2. Let’s Get To Know Magnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Chapter 4 ELECTRICITY IN YOUR LIFE

2. Motion of the Earth and the Moon. . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Chapter 6 THE WORLD OF LIVING THINGS

2. The Environment You Live In . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

Chapter 7 LIGHT AND SOUND

4. Substances That Are

Living things must eat:

Foods can contain more than one kind of nutrient.

Nutrients play important roles in keeping your

You must eat to be able to carry out activities like doing

8 PRIMARY SCIENCE 5 STUDENT BOOK

After water, proteins are the most abundant

Animal-based foods containing protein

Plant-based foods containing protein

Carbohydrates are the main source

Foods containing carbohydrates

10 PRIMARY SCIENCE 5 STUDENT BOOK

Fats act as a fuel, to provide the energy

These vitamins are a group. They are

Liver, milk, eggs, wheat, green beans,

Liver, milk, cheese, eggs, fish, fish oil,

12 PRIMARY SCIENCE 5 STUDENT BOOK

Answer the questions below about the pictures above.

1. Which are plant-based foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2. Which are animal-based foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3. Which come from neither an animal nor a plant source? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4. Which are produced from wheat? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5. Which are produced from meat? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6. Which are produced from milk? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7. Which come from the sea? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. Which are fruits? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9. Which are dried foods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14 PRIMARY SCIENCE 5 STUDENT BOOK

Write down the types of nutrients present in each picture below.

Providing Energy Regulating in

16 PRIMARY SCIENCE 5 STUDENT BOOK

1. .... to get the energy they need to run.

1. [......] Very small living things don’t need to eat.

2. [......] You get nutrients from food.

4. [......] All foods have the same taste.

5. [......] Energy is not found in vitamins and minerals.

6. [......] Milk is a plant-based food.

7. [......] Living things can’t live if they can’t eat.

A) They provide energy for the body.

18 PRIMARY SCIENCE 5 STUDENT BOOK

1. Transportation of Nutrients ▶ How Does Digestion Happen?

In the Gullet (Food Pipe): Gullet

In the Small Intestine:

In the Large Intestine:

20 PRIMARY SCIENCE 5 STUDENT BOOK

After eating food, enamel on the _ _

Time (min.) 1 2 3 4