FUN ACTIVITY SURVIVAL OF THE SPECIES

APPARATUS AND Scissors, glue, pictures of animals,

MATERIALS and manila cards.

STEPS
1. Select some examples of how animals ensure the survival of their young.
2. Draw or print some pictures of your choice of animals and their young.
Paste them on the folded manila cards as shown below.
3. Paste the pictures showing how the animals ensure the survival of their young
on each fold.

Animals take care of their young

Animals feed their young

Animals take care of their young Animals feed their young

4. Exhibit your work and discuss with

your friends.

(a) Why do animals protect their young? Explain.

(b) How do geese, lizards, and snails protect their eggs?

69
3.1.5, 3.1.6
 IMAGINARY ANIMAL

The pupils of Year 5 Zamrud are helping Mr Zaki to clean the school
storeroom that stores recyclable materials. The materials are collected
from the pupils and their parents during the recycling campaign conducted
by the Science Committee of the school. Observe the situation below.

Wow, there are so many

items! Let’s sort these
recyclable materials by their
types before selling them.

Surely we are
able to earn
some money.

70
3.2.1, 3.2.2, 3.2.3
 Mr Zaki, can I have some of
these boxes and tools?

Sure, Chan. What do ZAKI

you want to do with

them?

I want to do a project using

recyclable materials.

Oh, I see! The Science Committee of the school will be

organising a competition to create an imaginary animal model.
We have just learned about the specific characteristics and
behaviours of animals to protect themselves. I encourage all of
you to join the competition.
ZAKI

Sure, Mr Zaki. I will join it. This box will be used to

make the wings of my imaginary animal model.

Wow, that’s interesting! I will also

join the competition. This plastic
bottle will be used to make the nose
of my imaginary animal model.

That’s good. All your projects

will be displayed during the
science fair later.

ZAKI

71
 Let us look at the imaginary animal model made by Ana.

scales
antennae

wings small ear

lobes

nose sharp
spines

sharp
claws
thick and smooth
layer of fur This is the sketch of my
Name: Muri-muri imaginary animal model.
The sketch of Ana’s imaginary animal model
scales
protection from injuries
antennae
sensitive to touch

small ear lobes

wings
to reduce heat loss
small but strong
to fly high
sharp spines
nose for self-protection
very sensitive
to unfamiliar odours

thick fat
to control body
sharp claws temperature in
to scratch and grip cold weather
the enemy
thick and smooth layer of fur
thermal insulator in cold weather
This is a model of my imaginary animal Ana’s imaginary animal model
that has been completed. I named it
Muri-muri. Muri-muri is very unique, Great! Why are
special, and is capable of saving itself. there spikes on its
thick-fur body?

This is its speciality. Its thick and smooth fur can

deceive the enemy by hiding sharp spines for
self-protection. Its thick fur also functions as a
thermal insulator.

72
 Wow, that’s good, Ana! What about Melia,
Ravi, and Chan? I am sure your imaginary
animal models are also interesting to be
ZAKI

shared. Tell us about their specialities.

FUN ACTIVITY IMAGINARY ANIMAL

APPARATUS AND
A4 paper, pencils, and coloured pencils.
MATERIALS
STEPS
1. Sketch a model of your imaginary animal on the A4 paper.
2. Label the specific characteristics and behaviours of your imaginary
animal model.
3. Suggest the needed materials and apparatus to build your
imaginary animal model.
4. Then, make your imaginary animal model.
5. Present your work in front of the class.

(a) Explain the specific characteristics of your imaginary animal that can be
used to protect it from enemies and extreme weather.
(b) What will happen if your imaginary animal does not have the specific
characteristics as mentioned?
(c) In your opinion, why does God create different specific characteristics
for animals to protect themselves?
(d) How those characteristics ensure the balance of nature?

73
73
3.2.1, 3.2.2,
3.2.3, 3.2.4
 FOOD CHAIN

Living things in a habitat is interdependent for food sources. Identify the

animals in the situation below and state their food.

eagle

bird

snake squirrel

stork
monkey
otter

crab

crayfish

fish
74
3.3.1
Based on the situation at the mangrove swamp, what is the food for each
identified animal?

I observed a squirrel eating

a fruit and an otter eating
a fish.

What are the foods for other

animals such as crabs,
monkeys, snakes, and birds?

Crabs eat small animals. Birds and

monkeys eat fruits. Snakes eat
monkeys, birds, and squirrels.

Wow! It seems like all the animals

are interdependent. Some animals
eat plants and some eat other animals.

This means that the interdependence

among these animals is in the form of
a food relationship which is connected
like a chain.

ZAKI

Based on this situation, what is

the meaning of a food chain?

A food chain is the food relationship among living things.

75
 Therefore, based on all the living things identified in the habitat at the
mangrove swamp, we can state that:

eaten by eaten by eaten by

fruits squirrel snake eagle

The relationship is shown as follows:

fruits squirrel snake eagle

This food chain can finally be summarised as follows:

fruits squirrel snake eagle

arrow ( ) means eaten by

The food relationship among the living things

above is an example of a food chain in a
mangrove swamp habitat. Build examples of
other food chains in this habitat. ZAKI

76
3.3.1
 PRODUCER AND CONSUMER

Let us identify the producers and consumers based on the food chain
in a mangrove swamp habitat.

Do you still remember about photosynthesis? In the

presence of sunlight, plants make their own food.
Therefore, plants are called producers.
ZAKI

Mr Zaki, can other living

things be producers?

No, because only plants can carry out

ZAKI

photosynthesis. Where do plants get their

energy from?

Plants get their energy from the sunlight.

The sunlight is the source of energy for plants
to carry out the process of photosynthesis.

That’s right. So, can you identify the

producers and consumers by using
other examples of living things found
in the mangrove swamp?

ZAKI

77
3.3.2
 Producers obtain energy from the Sun. What about other animals such
as squirrels, otters, snakes, and eagles that cannot make their own
food? Where do these animals get their energy source from?

A squirrel is a consumer An otter is a consumer

that feeds on fruits. that feeds on fish.

Thus, the squirrel and otter obtain energy from the food they feed on.

Living things can also be related in terms of energy transfer as follows:

Squirrels are consumers that obtain

energy by eating fruits.

Snakes are consumers that obtain energy

by eating squirrels.

Eagles are consumers that obtain energy

by eating snakes.

arrow ( ) also shows the flow of energy transfer

in a food chain

What is the main source of energy for

the food relationship above? ZAKI

78
3.3.2
 FOOD RELATIONSHIP AND PHOTOSYNTHESIS
The relationship in
a food chain also
causes energy to be
transferred. Observe
the situation in this goat goat
farm.
Based on the identified duck
consumers and producer, chicken
energy transfer in several
food chains can be made
as follows: caterpillar
snake

vegetable duck snake

producer consumer consumer

Living things that are found

in this vegetable farm form
vegetable goat snake food relationships between
producer consumer consumer the producer and the
various consumers.

vegetable chicken snake

producer consumer consumer

ZAKI

vegetable caterpillar duck snake

producer consumer consumer consumer

vegetable caterpillar chicken snake

producer consumer consumer consumer

Thus, the food

Therefore, chain
the food also
chain shows
also thethe
shows food relationship among living
relationship
things in the
between terms of things
living energyin transfer.
terms of energy transfer.
79
79
3.3.3
3.3.3
 The diagram below shows the food relationship among living things.
It shows the process of photosynthesis in terms of energy transfer in the
food chain of a paddy field habitat.

The Sun is the main source of

energy in an ecosystem. The Sun
provides light and heat energy.

The paddy plant is the producer that

absorbs energy from sunlight to carry paddy plant
out the process of photosynthesis.

SCIENCE INFO
An ecosystem is an ecological
system of natural living things that live eagle
together, interact, and depend on one
another in a habitat. An ecosystem
Energy is transferred
includes its environments such as
to the end consumer
water, soil, air, and the Sun as the
source of energy. which is the eagle that
eats the snake. The
eagle also eats the duck
and the chicken.
80
 The duck and the chicken are among
the consumers that eat paddy plants.
Therefore, these consumers get
energy from the paddy plants.

duck

chicken

Energy is transferred to the next

consumer which is the snake that
eats the duck and the chicken.
snake

What is the importance of the food

relationship among living things in
terms of energy transfer? ZAKI

81
 FOOD WEB

Now, you have identified the living things

in several habitats including those in the
ZAKI

vegetable farm. Caterpillars, ducks, chickens,

goats, and snakes are the living things found
in this vegetable farm.

Below are the food chains that can be built based on the habitat in
the vegetable farm.
(a) vegetable duck snake

(b) vegetable goat snake

(c) vegetable chicken snake

(d) vegetable caterpillar duck snake

(e) vegetable caterpillar chicken snake

These food chains can be combined to form a food web as shown below.

goat

snake
chicken
vegetable

caterpillar

duck

What is a food web?

ZAKI

82
3.3.4, 3.3.5
 storks

snail
small fish

waterweed

tadpoles

frog
grasshopper big fish

Observe the pond habitat in the picture above. What are the living things
that can be found in the habitat?

There are waterweeds, small fish, big fish, tadpoles,

frogs, storks, grasshoppers, and snails in this habitat.

It seems that tadpoles, small fish, snails, and grasshoppers

also eat the same food which is the waterweeds.

Below are some food chains that can be built based on the pond habitat.
(a) waterweed snail stork
(b) waterweed tadpoles stork
(c) waterweed small fish frog stork
(d) waterweed grasshopper frog stork
(e) waterweed small fish big fish stork
(f) waterweed tadpoles small fish stork
(g) waterweed tadpoles big fish stork
(h) waterweed tadpoles small fish big fish stork

83
 Now, let’s combine all the food chains
that have been built into a food web
as shown below.
ZAKI

Mr Zaki, this is a food web diagram

that I have built based on all the
earlier food chains.

snail

tadpoles
big fish
small fish
stork
waterweed

grasshopper

frog

The food web can be summarised as shown below.

snail

tadpoles
waterweed big fish

stork
small fish
grasshopper

frog

Identify other food chains in this habitat

and combine them to form a food web.

84
ZAKI
 FUN ACTIVITY FOOD WEB
APPARATUS AND Marker pens, pictures of various
MATERIALS habitats, and manila cards.

STEPS

Group: 1
Habitat: pond
Producer: waterweed
Consumers: fish, stork,
grasshopper, frog, snail,
and tadpoles.

1. Observe the given pictures. 2. Discuss and identify the producer

Identify the habitats in the pictures. and consumers in each of these
habitats.

Group: 1 Group: 1 : 1
KUMPULAN
Habitat : KOLAM
Habitat: pond Habitat: pond
Pengeluar: Rumpai air
Producer: waterweed Producer: waterweed
Pengguna: Ikan, bangau,
Consumers:
belalang katak,fish,
siputstork,
Consumers: fish, stork, grasshopper,
dan berudu. frog, snail,
grasshopper, frog, snail, and tadpoles.
and tadpoles.
Rantai Makanan
Food chain
Food(a) rumpai air
chain siput bangau
Foodwaterweed
(a) chain snail stork
(a) waterweed snail
berudu bangau
stork
(b)
Food rumpai air
chain
waterweed
(b)(a) waterweed snail
tadpoles
tadpole stork
crane (b)(a) (c) rumpai air
waterweed
waterweed belalang
tadpoles
tadpole
snail katak
crane
stork bangau

waterweed
(c)(b) waterweed tadpole
grasshopper crane
frog stork waterweed
waterweed
(c)(b)Siratan Makanan grasshopper
tadpole frog
crane stork
siput
waterweed
(c) web grasshopper frog stork
(c) waterweed grasshopper frog stork Food
Food web rumpai air berudu bangau
Food web snail
Food web snail belalang katak
waterweed tadpoles
tadpole
snail stork
waterweed tadpoles
tadpole
snail stork
waterweed tadpole
grasshopper frog stork
waterweed tadpole
grasshopper frog stork
grasshopper frog

grasshopper frog

3. Build some food chains on the 4. Present your work in front of

manila cards. Based on the food the class.
chains, build a food web.

(a) What is the main source of energy in this habitat?

(b) Classify the producer and consumers in each habitat using
suitable graphic organisers. Discuss.

TEACHER'S Teachers prepare pictures of different habitats.

NOTE
85
85
3.3.4, 3.3.5, 3.3.7
 In the food web, energy is also transferred from one living thing
to another.
1
n
io
at
tu
Si

grasshopper

tadpoles

stork
waterweed
fish

What will happen if all the

fish die from poisoning?
2
n
io
at
tu

Be thankful. The relationship

Si

among these living things is still

complete and interdependent.

goat

chicken
snake
vegetable grasshopper

duck

Predict the effects on other living

things if all the vegetables in the
farm were destroyed due to a flood.
86
ZAKI
EFFECTS OF POPULATION CHANGE
In a habitat, the energy transfer occurs continuously in the food
chain. Any changes in the population of living things will affect the
whole ecosystem.

Mr Zaki, how does a population

change occur in a food chain?
ZAKI

There are many reasons for the changes in

the population of living things. For examples,
tremendous weather changes and the
spread of a pandemic.

Unplanned forest exploration.

Forest fire.

Illegal hunting activities.

SCIENCE INFO
A population is a group of living things
or species found in a habitat. Population
change indicates a change in the
number of species in the habitat.

87
3.3.6
 What are the effects on living things
if there is a population change in
the food web of a habitat?

Animals will lose their natural

ZAKI habitats and food resources. Animals
may also die or they have to move
elsewhere in search of a new habitat.

kangaroos
elephants

SCIENCE INFO
It is estimated that 480 million
animals died due to a bush fire in
Australia since the end of August
2019. At least 8000 koalas perished
in the fire. About 30 percent of the
koalas’ habitats are also destroyed. tiger

Population change in the food chain of a habitat

will disrupt other living things. Food relationships
among living things are also affected. This causes
a major change to food chains and food webs.

ZAKI

Predict other effects on living things due to a

population change in the food web of a habitat.
Describe.
88
 FUN SCIENCE MINI TERRARIUM

Build a mini terrarium using used materials such as aquariums, pebbles,

soil, small plants, and suitable small animals. Decorate your mini terrarium
creatively.

SCIENCE INFO
Terrarium is a transparent container used
to preserve plants or small animals by
creating a similar environment to their
natural habitats.

MIND REFLECTION
1. The survival of an animal species is the ability for animals to maintain their
species to avoid extinction.

2. Animals have specific characteristics on parts of their bodies and

behaviours to protect themselves from enemies as follows:
• big and sharp claws. • hard shells.
• stings that can release venom. • produce bad smell.
• patterns that resemble • hard scales.
fake eyes on the wings. • sharp horns.
• strong leg muscles. • raising quills with
• sharp spines. sharp spines.
• inflating the bodies that have • detaching parts of the bodies.
sharp spines. • withdrawing parts of the
• poisonous. bodies into the shells.
• spurting out black ink. • live in groups.
• curling up the bodies.

89
 3. Animals have specific characteristics on parts of their bodies and behaviours
to protect themselves from extreme weather as follows:
• thick fur. • hibernate.
• short and densed feathers. • small ear lobes.
• thick layers of fat. • migrate.
• wallow in water or mud. • humps.
• large ear lobes.

4. Animals protect their eggs in various ways as follows:

• hide their eggs. • lay many eggs.
• incubate their eggs. • slimy eggs.
• lay their eggs on the • smelly eggs.
surface of rocks.
• bury their eggs in the soil.

5. Animals ensure that their young survive in various ways as follows:

• protect their young. • feed their young.
• suckle their young. • place the young in their mouths.
• raise their young in pouches. • attack the enemies when their young
are in danger.

6. Survival of species is important for the balance of the ecosystem.

7. A food chain is the food relationship among living things.

8. A food web is a combination of more than one food chain.

9. Producers are living things that can make their own food by carrying out
the process of photosynthesis.

10. Consumers obtain energy from eating other living things.

11. The Sun is the main source of energy in an ecosystem.

12. The balance of an ecosystem will be affected when there is a major

population change in a habitat.

13. If population change occurs in a food web of a habitat, animals will lose
their natural habitat and food source. The animals may also die or migrate
to other places to look for a new habitat.
90
 MIND TEST
Answer all questions in the Science exercise book.
1. What is meant by the survival of animal species?
A. The ability of animals to protect their young.
B. Animals migrate to other places when there is no food.
C. Animals can prevent their species from extinction.
D. Animals have specific behaviours to find a mate.
2. Identify the following animals with their specific characteristics to protect
themselves from enemies.

(a) (b) (c) (d)

3. Match each phrase to the correct animal.

lays many eggs

incubates its eggs

produces slimy eggs

4. How do the following animals keep their young alive?

(a) (b) (c)

91
 5. Observe the situation below and answer the following questions:

A cat tried to catch a lizard but it

only managed to catch the tip of
the lizard’s tail.

(a) In your opinion, has the cat succeeded in catching the lizard?
Give an inference for your answer.
(b) What is the specific behaviour of the lizard that protects it from the cat?
(c) How can this behaviour protect the lizard?
(d) Give an example of another animal that has similar specific behaviour
as the lizard.
6. State the meaning of each of the following terms.

producer food chain food web

7. The diagram below shows the food web in a habitat.

J K L

M N O

(a) Build three food chains based on the living things in this habitat.
(b) How many omnivorous animals are present in this food web?
(c) If K were destroyed due to a pandemic, predict the impact on the
populations of N and O.
(d) What is the main source of energy, producer, and consumers
in this habitat?
(e) Based on the diagram, predict K, L, N and O.
(f) What is the importance of food relationship among living things?

92
 it
Un PLANTS
Look at these lotus plants. How do they
reproduce in the pond?
Look at the dandelion seeds too. Why
do the dandelion seeds fly when the wind
blows?

How do plants maintain their species?

SEKOLAH KEBANGSAAN SINAR

93
 PROTECTION FROM ENEMIES

Plants have various specific characteristics to protect

themselves from the enemies to ensure the survival
of their species.
How do these specific characteristics allow SEKOLAH KEBANGSAAN SINAR

plants to protect themselves from the enemies?

Let us observe the situation of Melia and her sister at their

grandfather’s orchard.
Ouch! The durian Be careful, little sister. These sharp
thorns are very sharp! thorns can hurt the enemies that
want to eat the durian.

durian pineapple
Sharp thorns

What is that,
grandpa?

This is the latex from the

jackfruit tree. It is sticky jackfruit tree
to prevent the enemies
from eating the fruits.

Produce latex
papaya tree
94
4.1.1
Oh no! This is itchy!

The fine hairs on bamboo

leaves are causing that itch.
Don’t touch the leaves. bamboo plant pumpkin plant

Fine hairs

That’s dangerous! Don’t

pick the flowers. The leaves,
stems, roots, and flowers
of the allamanda plant are
poisonous. The poison causes
poisoning or even death.

pong pong tree

allamanda plant
Poisonous
95
 Yuck! That stinks!

citronella plant

That is a citronella plant. Its leaves

produce strong bad smell so that the lantana plant
enemies will go away.
Bad smell

Sharp thorns, produce latex, fine hairs, poisonous, and bad

smell are the specific characteristics of plants that can protect them
from the enemies. These ensure the survival of the plant species.

State the specific characteristics of the rafflesias

that can protect them from the enemies.

HAWA

rafflesia

SCIENCE INFO
Citronella plants are also known as
mosquito repellent plants. These
plants are usually planted around the
house. The leaves release a smell that
mosquitoes dislike.
citronella plant
96
 FUN ACTIVITY PLANT SHIELDS
APPARATUS AND Pencils, containers, 25 picture cards
MATERIALS of plants with various specific
characteristics, and adhesive notes.
STEPS
1. Move to each station in groups.
STATION 2

STATI
ON 1
yam plant pudica
cactus

N1
T IO
STA pong pong tree bamboo plant

2. At the first station, observe the 3. Write the identified specific

pictures and identify the specific characteristics on adhesive notes
characteristics of the plants that and place them in the container.
are used to protect them from the
enemies.
4. Repeat steps 1 and 3 at each 5. After completing the task at all
station. stations, the group representative will
take a container from one station.
6. Discuss the answers in 7. Construct a mind map based on
the container. the result of the discussion.

(a) How do the specific characteristics of the plants in the pictures

protect the plants from enemies?
(b) Give some examples of other plants with similar specific characteristics
with the ones you have identified.

Prepare 25 photos of plants with different

TEACHER'S
orange yam plant
jasmine

NOTE specific characteristics. Place the apparatus

and materials at each station.
pudica

bamboo plant pong pong tree

97
4.1.1, 4.13
 ADAPTING TO CLIMATE AND SEASONAL CHANGES
Plants have specific characteristics to adapt
themselves during climate and seasonal
changes to ensure the survival of their species.

The weather is
so hot here.

I like this kind

of weather.

The wind is
so strong!

I’m not worried.

How do plants use their specific

characteristics to adapt themselves
to climate and seasonal changes? HAWA

98
4.1.2
Let us understand the following specific characteristics of plants to adapt
to climate and seasonal changes.

STRONG SEASONAL WIND

I’m a casuarina tree.

My tree trunk and
I’m a coconut tree. branches are
I have a flexible flexible and I have
trunk and split needle-shaped leaves
leaves that can that can reduce the
reduce the force of force of strong winds.
strong winds.

coconut tree casuarina tree

HOT CLIMATE AND DRY SEASON

I’m a cactus plant. I can survive in a

hot climate and during the dry season.
My leaves are modified as spikes to
prevent water loss. My stem can store
water and my long roots can absorb
water deep in the soil.

cactus plant
99
 I’m a tomato plant. My stem and
leaves are covered with fine hairs
to prevent water loss when the
weather is hot.

tomato plant

I’m a turmeric plant. I can roll my leaves

when the weather is hot to prevent water loss.

turmeric plant

I’m a yam plant. I have

waxy leaves to avoid
excessive water loss when
the weather is hot.

yam plant

100
I’m a rubber tree. I shed my
leaves when the weather is
hot and during the dry season
to avoid water loss.

rubber tree

COLD CLIMATE

I’m a maple tree. I have thick bark

covering my trunk to protect myself
from the cold climate.

maple tree

101
 needle-shaped leaves

Pine trees have specific characteristics to

survive during strong seasonal wind and
during hot and cold weather. Based on
the specific characteristics mentioned,
how do pine trees adapt themselves to
climate and seasonal changes? pine tree thick bark

Flexible trunks, split leaves, needle-shaped leaves, modified leaves as

spikes, water storing stems, long roots, fine hairs, rolling leaves, waxy
leaves, shedding leaves, and thick bark are the specific characteristics
of plants to adapt to climate and seasonal changes for the survival of their
species.

Bougainvillea trees will shed their leaves when the

weather is hot and during the dry season. Why?

HAWA

bougainvillea tree
SCIENCE INFO
Thick bark covering the trunks of trees prevent
the absorbed water from freezing in an extremely
cold climate.
102
 FUN ACTIVITY DIGITAL POSTCARD
APPARATUS AND Computer and internet access.
MATERIALS
STEPS

1. Use the internet to find information on plants and their specific characteristics
to protect themselves from enemies.
2. Download the information and pictures.

ARECA PALM Dear Azim,

Do you know that the areca palm

trees have specific characteristics to
adapt themselves for climate and
seasonal changes?

The areca palm trees

have flexible trunks to prevent
themselves from breaking when
strong winds blow.

Furthermore, the areca palm

trees have split leaves to reduce the
force of strong winds.
Do you know any other plants
that have the same characteristics
like the areca palm tree? Share
the information with me if you do
know about it.

Yours sincerely,
Suzana

3. Make a digital postcard using 4. Keep the digital postcard made

the downloaded pictures and in a folder.
information.

5. Upload the digital postcard

on Google Classroom.
ARECA PALM Dear Azim,

Do you know that the areca palm

trees have specific characteristics
to adapt themselves for climate
and seasonal changes?
The areca palm trees
have flexible trunks to prevent
themselves from breaking when
strong winds blow.
Furthermore, the areca palm
trees have split leaves to reduce
the force of strong winds.

Do you know any other plants

that have the same characteristics
like the areca palm tree? Share
the information with me if you do
know about it.

Yours sincerely,
Suzana

Describe the specific characteristics of the plant to adapt to climate and

seasonal changes that you have chosen for your postcard.

103
4.1.2, 4.1.3
 DISPERSAL OF SEEDS OR FRUITS

Plants have various ways to disperse their seeds or fruits to ensure the
survival of their species. Let us follow the story of the balsam parent plant
and its seeds to know how plants disperse their seeds or fruits.

!!!
POP

Good morning,
You were dispersed over there. my children.
Grow well and healthy, my little ones.

Good morning, mother.

Who are they?

They are the
What is happening
angsana fruits. They
to them? were dispersed far
away from their
parent plants.

104 4.2.1, 4.2.2,

4.2.3, 4.2.4
 Hi there, how were you dispersed here?

I was dispersed by the wind far

from my parent plant.

Dispersal by wind.
Characteristics of seeds or fruits:
wing • small. • thin.
• lightweight. • wing-like structure.
• fine hairs.
angsana fruit

Hello, coconut! How

were you dispersed?

Oh, I was dispersed

by water!

Dispersal by water.
Characteristics of seeds or fruits:
• waxy skin.
husk • husk with air cavities.
coconut
105
 Hi, who are you?

I’m a rambutan seed. My flesh was eaten

by a monkey and I was dispersed here.

Dispersal by animals and humans.

Characteristics of seeds or fruits:
• edible flesh.
• attractive colour.
• pleasant smell.
rambutan

Those are the burr mallow

seeds. They are dispersed
by animals.

Oh! What are those

that stuck on the
rabbits’ fur?

Dispersal by animals and humans.

Characteristics of seeds or fruits:
• small.
• lightweight.
• have hooks.
106 burr mallow seeds
 Wow! The seed pod is
drying and splitting!

Wow! I’ll have more siblings.

Dispersal by explosive mechanism.

Characteristics of seeds or fruits:
• seed pods dry out.
• seed pods split open.

garden balsam seeds

Now you know that plants are dispersed in different

ways. They are dispersed by wind, water, animals,
and humans as well as by explosive mechanism.

After reading the story of the balsam seed

and its parent plant, state the different
ways plants disperse their seeds or fruits.
HAWA

TEACHER'S Seed pods are hard skin of the seeds that break
NOTE when they mature. 107
 All seeds and fruits are dispersed in various ways to ensure the survival
of their species. Plants disperse their seeds or fruits by wind, water,
animals and humans as well as by explosive mechanism.

Ways of dispersal
of seeds or fruits
HAWA

Based on the characteristics

explained earlier, predict the ways
these seeds and fruits are dispersed.

mangosteen

dandelion

nipa palm fruit rubber fruit

Plants need to disperse their seeds or fruits far from the

parent plants. What type of dispersal method can disperse
the seeds or fruits farthest from their parent plants? Why?

108
 THE IMPORTANCE OF SURVIVAL FOR ANIMAL
AND PLANT SPECIES

Living things depend on each other to

HAWA
keep the balance of the nature.

Plants are a food source to other living things such as animals and humans. Animals and
humans in turn provide fertilizers and nutrients to plants through decaying process. Only
some of the animal and human faeces can be made into fertilizers.

Living things such as animals and humans also ensure the survival of plants species by helping
to disperse the seeds and fruits of the plants.

Animals make their nests using plants for protection. Plants also provide oxygen to other
living things during photosynthesis.

The interaction between living things

ensures the balance of the nature.
What will happen if plants are unable 4.2.1, 4.2.2, 109
to ensure the survival of their species?
HAWA

4.2.3, 4.2.4
 FUN ACTIVITY SEEDS AND WAYS
OF DISPERSAL
APPARATUS AND Marker pens, adhesive tape,
MATERIALS and flip chart paper.

STEPS

1. Discuss the relationship between 2. Construct a suitable mind map.

the characteristics of seeds and
their ways of dispersal.

3. Display your work in front 4. Present your work in front

of the class. of the class.

What is the relationship between the characteristics of

the seeds or fruits with their ways of dispersal?

Durians have sharp thorns to protect themselves from

animals and humans. However, animals and humans
are also dispersal agents for durians. Why?

110
4.2.2, 4.2.4
 FUN SCIENCE EXPLODING SEED POD
Create a simulation of seed dispersal by explosive mechanism using
a filter funnel, sharp pencil, measuring tape, balloon, and 100 g of beads.

STEPS

1. Insert the end of the filter funnel 2. Pour 100 g of beads into the balloon
into the balloon. using the filter funnel.

3. Blow air to inflate the balloon until it 4. Use the sharp pencil to poke
is big. Then, tie a knot. the balloon.

5. Measure the distance the beads

travelled from the spot where
the balloon was popped.

4.2.1, 4.2.2, 111

4.2.3, 4.2.4
 MIND REFLECTION

1. Plants have specific characteristics to protect themselves from the enemies.

The specific characteristics are:
• sharp thorns. • poisonous.
• produce latex. • bad smell.
• fine hairs.
2. Plants have specific characteristics to adapt themselves to climate
and seasonal changes such as:
(a) strong seasonal wind
• flexible trunks and branches.
• split leaves.
• needle-shaped leaves.

(b) hot climate and dry season
• modified leaves as spikes. • rolling leaves.
• water storing stems. • waxy leaves.
• long roots. • shedding leaves.
• fine hairs.

(c) cold climate
• thick bark.
• needle-shaped leaves.
3. Ways of dispersal and characteristics of seeds or fruits are:

(a) wind (b) water

• small. • waxy skin.
• thin. • husk with air cavities.
• lightweight.
• wing-like structure.
• fine hairs.
(c) animals and humans (d) explosive mechanism
• edible flesh. • seed pods dry out.
• attractive colour. • seed pods split open.
• pleasant smell.
• have hooks.
• small.
112 • lightweight.
 MIND TEST
Answer all questions in the Science exercise book.
1. Observe the pictures below. State the specific characteristics of the
plants to protect them from the enemies.
(a) (b) (c)

yam plant citronella plant poison ivy

2. State the specific characteristics of plants based on the given situations

to adapt themselves to climate and seasonal changes.

(a) (b)
Bamboo trees Pine trees can
can survive survive in cold
in areas with weather.
strong winds.

3. The following plants have different ways of seeds or fruits dispersal.

State their ways of dispersal.

(a) (b) (c) (d)

okra seed burr mallow seed dandelion seed lotus seed

113
 4. Observe the picture below.

(a) What are the specific characteristics of the

papaya fruits or seeds with their way of
dispersal?

(b) Predict the way of dispersal for the papaya

fruits or seeds.
papaya

5. Answer the riddles below on the way seeds or fruits are dispersed.
Predict the following seeds or fruits.

(a) I am light enough to float on water, Way of seed or fruit dispersal:

Soft and waxy, my skin won’t falter;
My fibrous husk is filled with air,
Take a guess what I am, oh do be fair. Predicted seed or fruit:

(b) The colour of my skin is very pretty, Way of seed or fruit dispersal:
I smell sweet, as you will agree;
My flesh is delicious, you cannot resist, Predicted seed or fruit:
Please go ahead and guess, I do insist.

(c) Living in a seed pod, we have to endure, Way of seed or fruit dispersal:
Once it is dried, we are all so mature;
When it splits open, off we are scattered,
If you know what we are, we would Predicted seed or fruit:
be so delighted.

(d) Lightweight and small with hooks all around, Way of seed or fruit dispersal:
I am not brightly coloured, dull it may sound;
Nor am I fleshy as I would like to be,
But I get the job done, can you guess what Predicted seed or fruit:
could be me?

(e) We are small in size and lightweight too, Way of seed or fruit dispersal:
With these thin wings, we can just fly through;
Just like a loose kite, we can go quite far,
Give it a guess, do you know what we are? Predicted seed or fruit:

114
 it
Un ELECTRICITY

Hmm, why can’t this television

be switched on?

Look, Ana! One of the Although one of the

bulbs is not working. bulbs is not working,
the others still light up.

Observe the situations above. Why do they happen?

115
 SOURCES OF ELECTRICAL ENERGY

We use electrical energy every day. Electrical energy is used to produce

light, heat, sound, and to move objects. What are the sources for
electrical energy?

POWER PLANT
Power plants use kinetic energy produced from winds, waves, and
hydroelectric to move turbines and generate electricity.

SOLAR CELL
Solar cells convert light energy from
the Sun into electrical energy. Solar
cells are also used in satellites and
calculators.

116
5.1.1
DRY CELL DYNAMO ACCUMULATOR GENERATOR
Dry cells store When wheels rotate, Accumulators Generators
chemical energy. a small wheel convert chemical convert
The chemical of the dynamo energy into chemical
energy is also rotates. The electrical energy. energy from
converted into dynamo converts It is used to start fossil fuels
electrical energy kinetic energy into up vehicles such as into electrical
to move tools electrical energy cars. energy.
such as toy that can light up a
cars. Dry cells bicycle light.
are often used
because of their
small size and
easy to bring
everywhere.

Explain the examples of TEACHER'S Energy from the Sun is also

NOTE known as solar energy.
sources for electrical energy.
117
ZAKI
 SERIES CIRCUIT AND PARALLEL CIRCUIT

Bulbs and other electrical components can be connected into two types of
circuits. They are series circuit or parallel circuit.

SERIES CIRCUIT

In a series circuit, each bulb is arranged in one chain.

dry cell

one chain of
electric circuit

switch bulbs

Based on the arrangement of the circuits

that you have learned, how many paths
for the electric current to flow in series and
parallel circuits?

Series circuit has a single path for the electric current to flow.

one path of
electric current

118
5.2.1
 Observe the circuit below. What is the difference between
the arrangement of bulbs in series and parallel circuits in
a complete circuit? ZAKI

PARALLEL CIRCUIT
In a parallel circuit, each bulb is arranged in several branches that are
parallel to each other.

dry cell first branch of the

electric circuit

switch bulb second branch of the

electric circuit that is parallel
to the first branch

switch bulb

The electric current in parallel circuit can flow in more than one path.

first path of the

electric current
second path of the
electric current

119
 SKETCHING USING SYMBOLS

In a circuit diagram, electrical symbols are used

to represent the components in an electric circuit.

Let’s look at the symbols for the ZAKI

components in an electric circuit.

COMPONENT SYMBOL

Dry cell

1 dry cell

2 dry cells

Switch

open switch

closed switch
open switch closed switch

Bulb

Sketching using the electrical symbols is easier to understand as compared

to using the pictures of actual components. It shows the connections of the
electrical components more clearly.
120
5.2.2
 Let’s sketch the
diagram for this
series circuit. 1. Sketch the symbol of the dry cell.

2. Then, sketch the symbol of 3. Sketch a linear connection

the bulbs. between the dry cell and the bulbs.
Lastly, insert the symbol for the switch.

How do I sketch
the parallel circuit?

1. Sketch the first branch of 2. Then, sketch the second branch of

the electric circuit. the electric circuit in parallel.
121
 SKETCHING ELECTRIC
FUN ACTIVITY C IRC U I T D I A G R A M S
USIN G S YM B O L S
APPARATUS AND Series circuit and parallel circuit
MATERIALS arrangements, marker pen, A4 paper,
and ruler.
STEPS

1. Observe the arrangement of the 2. Take turns to sketch the symbol for
series circuit. Then, sketch the each dry cell, switch, and the bulbs
symbol for the dry cell on the A4 in the series circuit.
paper.

3. Connect the symbols of the 4. Repeat steps 1 to 3 for parallel

components with the symbol of the circuit arrangement.
connecting wire in linear lines.
5. Share the sketch of the circuit diagrams of your group in front of the class.

(a) Explain all the symbols for the electrical components that you
have sketched.
(b) Compare the positions of the actual components with the sketched
symbols in the circuits. Are the connections of the components
shown clearly?

122 TEACHER'S Teachers prepare the arrangement for

5.2.2, 5.2.7 NOTE the series and parallel circuits.
THE BRIGHTNESS OF BULBS

What is the difference in the brightness of the bulbs

between the series and parallel circuits?

A B D

Series Circuit Parallel Circuit

Wow! It looks like the bulbs arranged in the parallel circuit are
brighter than the bulbs arranged in the series circuits.

Why do the bulbs arranged in

the parallel circuit light brighter?

The series circuit has one path

for the electric current to flow.
All the bulbs share the electric
current.This causes bulbs A and
B to be dimmer than the bulbs
A B arranged in the parallel circuit.

The parallel circuit has more than one path for the
C electric current to flow. The total electrical energy
that flows through each path is the same. This
causes bulbs C and D to be brighter than the bulbs
D arranged in the series circuit.

123
5.2.3
 THE BRIGHTNESS
LET’S TEST
OF BULBS
To investigate the relationship between types of circuit
AIM and the brightness of bulbs.
APPARATUS AND Four bulbs, four bulb holders, four dry cells, four
MATERIALS dry cell holders, two switches, and connecting
wires with crocodile clips.
STEPS

1. Build a series circuit using 2. Then, build a parallel circuit using

two bulbs. the same number of bulbs.

3. Close the switches in both circuits 4. Observe the brightness of the bulbs
simultaneously. in both circuits.

(a) What are your observations on the brightness of the bulbs

in this activity? Explain.
(b) What can you conclude from your observations?

Ozair arranges five bulbs for two different arrangement

of circuits. Which circuit lights brighter bulbs? Why?

Circuit A Circuit B
124
5.2.3, 5.2.7
 FACTORS AFFECTING THE BRIGHTNESS OF BULBS
IN SERIES CIRCUIT

NUMBER OF DRY CELL

Can we make the bulbs in

this series circuit brighter?

If we increase Let’s test this

the number of dry hypothesis
cells, the bulbs by carrying
will light brighter. out an
experiment.

1. Aim
To determine the factors affecting the brightness of the bulbs
in a series circuit.
2. Problem statement
Does the number of dry cells affect the brightness of the bulbs
in a series circuit?
3. Hypothesis
As the number of dry cells increases, the brightness of the bulbs in
a series circuit also increases.
4. Variables
• manipulated: number of dry cells.
• responding: brightness of the bulbs.
• constant: number of bulbs and type of circuit.
5. Apparatus and materials
Three bulbs, three bulb holders, six dry cells, six dry cell holders,
three switches, and connecting wires with crocodile clips.
125
5.2.3, 5.2.4, 5.2.5
 6. Steps
(a) Build three series circuits as follows:
(i) A series circuit using a bulb and a dry cell.
(ii) A series circuit using a bulb and two dry cells.
(iii) A series circuit using a bulb and three dry cells.
(b) Then, close the switches simultaneously.
(c) Observe the brightness of the bulbs and record the results in the
table as shown below.
7. Data
Brightness of bulbs
Number of dry cells
brightest brighter bright
1
2
3
8. Conclusion
(a) Hypothesis is (accepted/not accepted).
(b) As the number of dry cells ______, the brightness of the bulbs also ______ .

NUMBER OF BULB
Melia, in your opinion, does the brightness of the bulbs increase
by increasing the number of bulbs in this series circuit?

No, Chan. In
my opinion, the
brightness of the
bulbs in a series
circuit will decrease
if the number of
bulbs increases.

Let’s carry out the experiment again to

prove the hypothesis above.
126
 IN PARALLEL CIRCUIT
NUMBER OF DRY CELL

Does the number of dry cells

affect the brightness of the
bulbs in a parallel circuit?

How do we change
the brightness of the The brightness of the bulbs can be changed by adding
bulbs in a parallel more dry cells. The increase in the number of dry cells will
circuit? provide more electrical energy to the circuit. The increased
amount of electric current that flows in each branch of the
circuit causes the bulbs to lit up brighter.

As the number of
dry cells increases,
the brightness
of the bulbs in a
parallel circuit also
increases.

one dry cell two dry cells three dry cells

Circuit A Circuit B Circuit C

Based on Circuits A, B and C, plan an experiment to

investigate whether the number of dry cells affects
the brightness of the bulbs in a parallel circuit.
127
 NUMBER OF BULB

Ana, in your opinion, I don’t think so, Ravi.

does the brightness A parallel circuit has more
of the bulb in than one path for the electric
a parallel circuit current to flow. Therefore,
decrease if the the total amount of electricity
number of bulbs that flows in each path is
increases? the same.

I agree with you, Ana.

When the number of bulbs
increases, the brightness You can carry out
of the bulbs in a parallel an experiment
circuit does not change. to prove the
hypothesis.

one bulb two bulbs three bulbs

Wow, the bulbs in all

three parallel circuits
have the same
Circuit A
brightness!

Circuit B

This proves that when the

number of bulbs increases, Circuit C
the brightness of the bulbs in a
parallel circuit does not change.

What is your conclusion about the factors

affecting the brightness of bulbs in series and
parallel circuits?

128
 CLOSED SWITCH, OPEN SWITCH
Ravi has built a series circuit. He has connected two switches in the circuit
to observe the condition of the bulbs when these switches are closed
or opened.

What is the condition of the bulbs if

I open or close the switches in this
series circuit?

Switch X Switch Y Switch X Switch Y

is opened is closed is closed is opened

Why do both bulbs in this series circuit not

light up if one of the switches is opened?

When either switch X or Y is opened, both bulbs do

not light up. This is because the circuit has become
an incomplete circuit and electric current cannot flow.

129
5.2.6
 Chan also tested the condition of the bulbs when one of the switches is
opened or closed in the parallel circuit that he has built.

Why does the other bulb still light

up although one of the switches in
the parallel circuit is opened?

Switch X is opened A Switch X is closed A

Switch Y is closed B Switch Y is opened B

When switch X in the first branch of When switch Y in the second branch
the electric circuit is opened, bulb A of the electric circuit is opened, bulb
in the first branch does not light up B in the second branch does not
because the circuit on this branch light up because the circuit on this
becomes an incomplete circuit and branch becomes an incomplete circuit
the electric current cannot flow and the electric current cannot flow
through it. through it.

Bulb B in the second branch Bulb A in the first branch

of the electric circuit still lights of the electric circuit still
up because electric current lights up because electric
can flow through this branch. current can still flow
through this branch.
130
 CLOSE THE SWITCH,
LET’S TEST OPEN THE SWITCH
To investigate the relationship between the
AIM conditions of switches and bulbs.
Six bulbs, six bulb holders, four dry cells, four dry
APPARATUS AND
cell holders, six switches, and connecting wires
MATERIALS with crocodile clips.
STEPS

1. Build a series circuit using three 2. Build a parallel circuit using three bulbs
bulbs and three switches. Label and three switches. Label the bulbs as
the bulbs as A, B, C and the D, E, F and the switches as S4, S5, S6.
switches as S1, S2, S3.
3. Close the switches in both circuits simultaneously.
4. Then, open and close the switches by following the instructions in the table
as shown below. Record your observations.

Circuit Condition of switches Condition of bulbs

S1 S2 S3 A B C

Series close open open does not light up does not light up does not light up
circuit open close open
open open close
S4 S5 S6 D E F

Parallel close open open

circuit open close open
open open close

(a) State the condition of the bulbs if S1 is closed while S2 and S3 are
opened. Give an inference to your observation.
(b) Which bulb will light up if S5 is closed while S4 and S6 are opened?
131
5.2.6, 5.2.7
 FACTORS AFFECTING THE USAGE
OF ELECTRICAL ENERGY

Electrical energy makes our life easier and comfortable. The mishandling
of electrical appliances causes higher usage of electrical energy. We
have to pay the cost of the electrical energy used. Using electrical energy
wisely can reduce our monthly electricity bill.

Using a fan instead of

an air conditioner.

Switching off the lights

when sleeping.

Switching off electrical Avoid leaving the

appliances when not in use. refrigerator door open
for a long time.
132
5.3.1
 What are the factors affecting the
usage of electrical energy?

Legend:
Type of electrical appliance used
Duration of using the electrical appliance

SCIENCE INFO
Green technology is a method to make or manufacture sustainable
products using recyclable and environmentally friendly sources
that do not cause pollution. An example of green technology is the
light-emitting diode (LED) lamp that is used to reduce the usage of
electrical energy.

Reduce the usage of water

heater when showering.

LED lamp compact filament lamp

fluorescent
lamp

Using energy-saving lamps such as

LED lamp and compact fluorescent
lamp instead of filament lamp.

XYZ789

State ways to reduce the usage of electrical

energy in the situation above.
ZAKI 133
 ANALYSING THE USE
FUN ACTIVITY OF ELECTRICAL ENERGY
AT HOME
APPARATUS AND
Copies of the monthly electricity bill.
MATERIALS
STEPS
Total
Total Payment (RM)(RM)
payment

500 Electricity Bill

400

300

200

100

Month
0
March April May

1. Gather the electricity bills of your 2. Observe the total amount paid
friend’s house for the past several for each month. Build a bar chart
months. based on the gathered information.

Use electrical
appliances that are
energy efficient.

Switch off
the lights when
not in use.

Dry clothes under WAYS TO SAVE

the Sun instead
of using a ELECTRICAL
clothes dryer. ENERGY Use a fan
instead of an
air conditioner.

Close the
refrigerator
Unplug electrical
door after
appliances that
use.
are not in use.

3. Gather information about how the 4. Suggest ways to save electrical

electrical appliances were used energy in a house in the form of
through an interview or a house visit. a mind map.

State ways to reduce the usage of electrical energy

in a house.

134
5.3.1, 5.3.4
 MISHANDLING OF ELECTRICAL APPLIANCES

The fire happened as a

result of a short circuit.

Electricity has various uses. However, mishandling electrical appliances is

very dangerous.
The following are examples of mishandling of electrical appliances.
Electrocution

Touching a switch or an Inserting an object that conducts

electrical appliance with electric current into the socket.
a damp or wet hand.

135
5.3.2
 Short circuit

Using an electrical appliance Connecting too many plugs

with a damaged wire. in a socket.

Fire

Mishandling of an Charging an electrical appliance

electrical appliance. for too long.

Siti covers a light bulb using a towel to make the

light dimmer in her room. Based on her action,
what is the effect that could happen?
136
 HANDLING ELECTRICAL APPLIANCES SAFELY

If we got electrocuted by a large amount of electric current, we may

experience injury and it can be fatal. Therefore, we must practise safety
precautions when handling electrical appliances.

How do we use electrical

appliances safely?

Faulty electrical appliances should be repaired by certified personnel.

Hands must be dry when touching a switch.

137
5.3.3
 Connect only one plug to one socket.

Turn off the switch before removing the plug from the socket.

Replace a damaged wire with a new one.

138
 SAFETY CARD AND
FUN ACTIVITY SAVING ELECTRICAL
ENERGY
APPARATUS AND Computer, internet access, scissors, glue,
MATERIALS manila card, and adhesive tape.

STEPS

1. Identify the places with electrical 2. Use the computer and the internet
appliances in your school such as to gather information about the
the canteen, computer laboratory, safety precautions and ways
and library. Mark the locations to save energy when handling
of the electrical appliances using these electrical appliances.
adhesive tape. Print the gathered information.
ELECTRICAL
SAFETY TIPS

ELEC
SAFE TRICA
ELECTRICAL TY TI L
SAFETY TIPS PS

AL
TRIC IPS
ELECFETY T
SA

3. Cut the manila card into smaller cards. 4. Paste the safety cards on the
Paste the gathered information onto marked locations. Present your
these cards to make cards on safety work to other groups.
precautions and saving electrical energy.
.
Explain the safety precautions needed when handling
the electrical appliances.
139
5.3.3, 5.3.4
 FUN SCIENCE CIRCUIT BOARD QUIZ
Construct a circuit board quiz
CIRCUIT BOARD
using a mounting board, QUIZ

coloured paper, paper clips,

Questions Answers

The main source survival of their

adhesive tape, connecting of energy in the

ecosystem
species.

Circuit board quiz

wires with crocodile clips, dry Plants disperse their
seeds to ensure
is the Sun.

cells, bulbs, dry cell holders, If the number of

bulbs increases,
the brightness of the bulbs
in a parallel circuit
waste products.

hole puncher, and glue. Blood carries oxygen, does not change.
nutrients, water, and

STEPS Joints are the meeting

point of two
bones.

CI
CIRCUIT BOARD

RC Q
QUIZ

Qu

UI UI
CIRCUIT BOARD

es
Th f en osy

T Z
tio
e er st
o ec

BO
QUIZ

m gy em

ns
ain in
Questions Answers

A RD
so th
Pla see

ur e
nt ds

ce
s d to
Questions Answers The main source
survival of their
isp en

of energy in the

An
er su
species.

sw
se re
ecosystem
th in

If

er
th

su s
e
bu ghtn ara
th s iness el c

s
bri a

eir

rv pe
e c of ir
lb

iva cie
nu re th cu

The main source

survival of their
m as e it
p

l o s.
be es b

of energy in the
Blo utrie

ft
r o , ulb

species. Plants disperse their

ll

he
f

ecosystem
n
od nt

seeds to ensure is the Sun.

ir
ca s, w
rrie a

is
s

th
Jo

s o ter,

e
in

Su
xy an
ts

If the number of
n.
ge d
ar t o

bulbs increases,
po
e

as
n,

the brightness of the bulbs waste products.

in
th f tw

te

in a parallel circuit
e

pr
m o

od
ee

uc
tin

do

ts
g

es

Blood carries oxygen,

no

does not change.

tc

nutrients, water, and

ha
ng
e.
bo

Joints are the meeting

ne

bones.
s.

point of two

1. Prepare written or printed 2. Make a hole on the top 3. Using the paper clips,
questions and answers part of the mounting clip one side of each
for the quiz. Paste the board. coloured paper with the
questions and answers questions and answers.
randomly on the mounting
board.

CIRCUIT

Questions

The main source

of energy in the
ecosystem

Plants disperse their is the

seeds to ensure

If the number of
bulbs increases,
the brightness of the bulbs waste produ
in a parallel circuit

Blood carries oxygen,

does not cha
nutrients, water, and

Joints are the meeting bones.

point of two

4. Build an electric circuit using 5. Insert the bulb through 6. Connect the paper clips
the connecting wires with the hole from the back for a question to the
crocodile clips as shown of the mounting board. respective correct answer
above. Fasten it using the using the connecting
adhesive tape. wires at the back of the
mounting board.
7. Touch one end of the
CIRCUIT BOARD
QUIZ

crocodile clip to the paper

Questions Answers

The main source survival of their

of energy in the species.
ecosystem

clips for the questions.

Touch the other end of the
Plants disperse their is the Sun.
seeds to ensure

crocodile clip to the paper

If the number of
bulbs increases,
the brightness of the bulbs waste products.
in a parallel circuit

Blood carries oxygen,

nutrients, water, and
does not change.
clips for the answers.
Joints are the meeting bones.
point of two

140
140
 MIND REFLECTION
1. The sources of electrical energy are from solar cells, dry cells, dynamos,
accumulators, generators, and power plants that use winds, waves, and
hydroelectric.
2. Bulbs can be arranged in series or parallel circuits.
3. Examples of sketches of series and parallel circuits using symbols are
as follows:

The sketch of a series circuit The sketch of a parallel circuit

4. The brightness of bulbs in a circuit can be changed by:
• changing the number of bulbs or the number of dry cells in a series circuit.
• changing the number of dry cells in a parallel circuit.

5. The differences in the condition of the bulbs between series and parallel circuits
when a switch is opened are as follows:

Series circuit Parallel circuit

Switch X is opened
Switch X Switch Y
is opened is closed Switch Y is closed

All the bulbs do not light up. The bulb in branch Y still lights up.

6. Factors affecting the use of electrical energy:

• Using a fan instead of an air conditioner.
• Switching off the lights when sleeping.
• Switching off electrical appliances when not in use.
• Avoid leaving the refrigerator door open for a long time.
• Reducing the usage of water heater when showering.
• Using energy-saving lamps such as the LED lamp instead of filament lamp.

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 7. The effects of mishandling electrical appliances:
• electrocution.
• short circuit.
• fire.
8. The safety precautions when handling electrical appliances:
• Faulty electrical appliances should be repaired by certified personnel.
• Hands must be dry when touching a switch.
• Connect only one plug to one socket.
• Turn off the switch before removing the plug from the socket.
• Replace a damaged wire with a new one.

MIND TEST
Answer all questions in the Science exercise book.

1. State all the sources of electrical energy.

2. Observe the circuit components below.

bulbs switches dry cell connecting wires

with crocodile clips
(a) Using all the components above, sketch the circuit diagrams for two
different circuits using symbols.

(b) Which arrangement has brighter bulbs? Why?

(c) Explain the difference in the arrangement of the bulbs in the series and
parallel circuits in the table as shown below.

Circuit Series Parallel

Arrangement
of bulbs

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3. Ali is investigating the brightness of bulbs in parallel circuits.

Circuit A Circuit B Circuit C

Based on the circuit diagrams above,

(a) what is the manipulated variable in this investigation?
(b) arrange the brightness of the bulbs in the three circuits in descending order.
(c) Ali then investigates another factor that affects the brightness of the bulbs
in a parallel circuit. His investigation is shown in the diagrams below:

Circuit A Circuit B

Based on the circuit diagrams above, is there any differences in the brightness
of the bulbs in both circuits? Why?

4. Based on the circuit diagram below, suggest two ways to increase the
brightness of the bulbs.

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 5. The diagram shows four bulbs Switch S3 Bulb M3
that are arranged in parallel
and series circuits. Each
switch is closed. Based on the
arrangement of the switches
Switch S2
and bulbs in the diagram, state Switch S4 Bulb M4
the condition of the bulb if one
of the switches is opened.
Bulb M2
(a) Switch S1
(b) Switch S2
(c) Switch S3 Switch S1 Bulb M1

6. Observe the situation below on the usage of electrical energy

in Ahmad’s house.

List ways for Ahmad to reduce the usage of electrical energy at his house.

7. The situation below shows a mishandling of an electrical appliance.

(a) What is the possible effect on the pupil?
(b) How could the mishandling be avoided?
(c) Give two safety precautions when handling
electrical appliances.

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