Exp SC 4 - Chapter 10
Exp SC 4 - Chapter 10
Exp SC 4 - Chapter 10
and Survival
Expected Learning Outcomes
Knowledge to be gained : • Kinds of animals • Adapta ons for habitat • Adapta ons for food
• Adapta ons for protec on
Skills to be developed : • Classifying animals based on their characteris cs.
A tude to be inculcated : • Live and let live.
KINDS OF ANIMALS
Animals are of two kinds:
1. Animals without a backbone, and Head
2. Animals with a backbone
Thorax
Animals Without a Backbone
A large variety of small animals such as, bugs, insects,
worms, spiders, scorpions and snails do not have a Abdomen
backbone.
Generally, insects have six legs and their body is divided
into three parts: head, thorax and abdomen. Insects have a Body of an insect
hard outer covering made up of a material called chitin. Most insects can y.
Frog
Bird
Birds have light bones and body. ey are
covered with feathers. ey have only two
legs and two wings that help them y, e.g.,
parrot, sparrow, crane, etc. Birds fly in the air
Mammals
These animals give birth to babies. eir bodies
have hair and the mothers suckle their young
ones. Most mammals breathe using lungs. ey
have four limbs. Mammals, like birds, are warm-
blooded animals. Warm-blooded animals have
the same temperature inside their body all the
time, e.g., horse, cow, humans, elephant, cat, dog,
etc.
Some mammals
Reptiles
Many animals live mainly on land. They
have scaly skins and reproduce by laying
eggs. They are called reptiles. Lizards,
salamanders, snakes and crocodiles are all
reptiles. Most of these animals breathe
through their moist skin. Reptiles take the
temperature of their surroundings. They Reptiles
are said to be cold-blooded animals.
Do
You ? Bat is the only mammal
that feeds on blood.
Know
ADAPTATION
Just like plants, animals also live in a variety of habitats. In fact, animals live everywhere on
the Earth. But all places on the Earth do not have the same kind of conditions and all
conditions do not favour the survival of animals. Animals have, thus, developed different
features which enable them to cope with difficult situations of living. This process, as you
know, is called adaptation. The animals that adapt to their habitat or environment are able
to survive. The ones that are not able to adapt, die and slowly become extinct. We can define
adaptation as a change in structure, function and behaviour by which an individual
improves its chances of survival in a specific environment.
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Honeybee
Bird
ADAPTATIONS TO HABITAT
Animals are found everywhere: in the plains, on trees, in air, in the deserts, on the
mountains and in water.
The natural home of an animal is called its habitat. Animals can be grouped according to
their habitat. They are grouped as terrestrial, aquatic, amphibian, arboreal, and aerial
animals.
Terrestrial Animals
Animals, like horses, lions and camels, live on land and are called terrestrial animals.
ese animals have legs which help them to walk on land and most of them have lungs as
breathing organs.
In the polar regions, it is quite cold. Animals
which live in very cold places have thick fur on
their body to protect themselves from the
cold, e.g., yak, polar bear, etc.
During extreme winters, food is not easily
available. In this period, animals like polar
bears use the fat stored in their body as food.
Polar Bear
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Animals like bears and frogs become inactive and sleep for several months in cold areas, to
protect themselves from cold. This is called hibernation or winter sleep.
Some animals such as seals, penguins and
walruses are adapted to living in freezing
conditions. ey have a thick layer of fat
called blubber under their skin to keep the
body warm.
Animals such as frogs and snakes cannot
bear extreme cold. erefore, they spend
the winter by hiding in safe and warm
places.
Animals living in deserts, such as camels,
have very little hair on their body. ey A camel in a desert
also have special organs to store water in their body for later use, because water is not easily
available in deserts.
Some animals in the deserts settle down to a long sleep in the hot summer months, to save
water. is is called aestivation or summer sleep.
CHECK YOURSELF
Aquatic Animals
Animals that live in water are called aquatic animals. Aquatic animals breathe in oxygen
dissolved in water. Generally, aquatic animals breathe through gills. Some of them, such as
whales and dolphins, breathe through lungs.
Aquatic animals
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Most aquatic animals have ns or paddles to help them swim. For example, crab, octopus,
turtle, etc. Fish have ns, while turtles have paddles to swim through water.
Amphibian Animals
Some animals, such as, frogs and toads, can live both on
land and in water. ey are called amphibians. e back
legs of frogs and toads are stronger than their front legs
to help them jump. Webbed feet and tails in some
animals allow them to swim in water.
Webbed feet of a frog
Arboreal Animals
Some animals that live on trees are called
arboreal animals. ey have sharp claws to
climb up and down the branches and usually have
strong muscular limbs and a tail for holding on to
the branches. For example, monkey, koala bear, etc.
Parasites
Many small animals get their food from other living
organisms by living in their bodies. ey are called
parasites. ey get their food by sucking the blood
of their host. ey may live on or inside their host.
Fleas, lice, bed bugs, etc., live on the body and suck
blood, while tapeworms, roundworms and
hookworms live inside the host animal's body.
Parasites
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CHECK YOURSELF
A. Tick (3) the correct option:
1. Which of these is an arboreal animal?
(a) Peacock (b) Monkey (c) Cat
2. Carnivores have sharp, pointed and curved front teeth called:
(a) molars (b) incisors (c) canines
ANIMALS IN DANGER
Lives of several animals are in danger
because we are cutting down forests for
our needs. By doing so, we are taking away
their homes and their food. Some animals
like the Dodo are already extinct, and
those like the Giant Panda are endangered
(i.e., they are on the verge of extinction).
Giant Panda
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CHECK YOURSELF
A. Tick (3) the correct option:
1. Which of these animals can blend with its surroundings and confuse its enemies?
(a) Polar bear (b) Giraffe (c) Duck
2. Which of these is classified as an endangered animal?
(a) Elephant (b) Giant panda (c) Dodo
New words
Ex nct animals : animals that have vanished from the Earth
Terrestrial animals : animals that live on land
Aqua c animals : animals that live in water
Arboreal animals : animals that spend most of their me on trees
Aerial animals : animals that can fly
Scavengers : animals organisms that feed on dead animals
Cold-blooded : animals organisms that can change their body temperature
Hiberna on : a long winter sleep taken by animals
Aes va on : a long summer sleep taken by animals
Migra on : mass movement of birds from colder to a warmer places
Camouflage : the ability to merge with the surroundings
Parasites : animals that live in or on the bodies of other animals
SUMMARY
v Insects have a hard outer covering made up of a material called chitin.
v The animals that adapt to their habitat or environment are able to survive.
v There is a large variety of animals that live in water.
v Birds have light bones and body which help them fly.
v Reptiles adapt to the temperature of their surroundings.
v Mammals give birth to babies.
v Generally, aquatic animals breathe through gills.
v Some animals live on trees, they are called arboreal animals.
v Man is an omnivore.
v Some animals have very strong legs and are able to run very fast.
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Exercise
A. Name the following:
1. A small animal with six or more legs. ________________
2. A long summer sleep taken by animals. ________________
3. Animals living on trees. ________________
4. A long winter sleep taken by animals. ________________
5. Animals that y in the air. ________________
6. Animals that eat esh of other animals. ________________
7. Animals that eat both plants and animals. ________________
8. Animals that suck blood. ________________
B. Answer the following questions:
1. What is hibernation?
2. What are the three parts of an insect’s body?
3. What do we call the animals which eat the esh of dead animals only?
4. What is the difference between hibernation and aestivation?
C. Fill in the blanks with the correct words:
1. Aquatic animals have _______________ or _______________ to help them
swim. ( ns/gills/paddles/oars)
2. Most birds can y because they have _______________ bodies. (light/heavy)
3. _______________ and _______________ have a backbone.
(reptiles/worms/ sh/sponges)
4. ________________ can live both on land as well as in water.
(Mammals/Amphibians)
5. Man is also a/an ________________. (herbivore/omnivore)
D. True or False:
1. e natural surroundings in which an animal lives is called adaptation.
_________
2. Animals that live both in water and on land are called amphibians. _________
3. Animals that spend most of their time on trees are called aquatic. _________
4. A giraffe is an omnivore. _________
5. Animals that live on or inside the body of other animals are
called parasites. _________
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E. Match the following correctly:
1. Terrestrial animal (a) Eagle
2. Arboreal animal (b) Kangaroo
3. Endangered animal (c) Squirrel
4. Parasitic animal (d) Hyena
5. Scavenger (e) Tape worm
6. Aerial animal (f) Panda
F. Pick the odd one out in the given case in each of the mentioned basis:
Activity Time
Class Activity
Divide your class into five groups. Each group should select one habitat and collect
information about the animals in it. Role play one animal from the habitat of your group.
Talk about its special features and how they help the animal to survive in its habitat. You
may make a mask of the animal you are role playing while giving your presentation.
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Let Us Visit
Have your parents ever taken you to a zoo? You should plan a visit to a zoo with your
friends and teacher.
You will nd all kinds of animals
in a zoo. You will nd terrestrial
animals, aquatic animals,
reptiles, arboreal animals, aerial
animals, etc.
Observe the animals and click a
few photos. Paste the photos in
your notebook and note down
what you have observed about
the animals.
Be a young
Researcher
Find out about the endangered animals found in India. Also nd out how we can protect
them.
FOOTNOTE
• Discuss how claws and a muscular tail help arboreal animals.
• Suggest for a trip to the zoo so that the students are able to see different animals.
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