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MY LIVING WORLD
(Class-IV)
Publication Division
D.A.V. College Managing Committee
Chitra Gupta Road, New Delhi-110055
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CONTENTS
S.No.
1.
Topic
Page No.
My Body
1-9
2. Plants
10-15
3.
Flowers and Fruits
16-23
4.
Plants Arounds Us
24-31
5.
Birds—Beaks and Claws
32-42
6. Insects
43-50
7. Food
51-60
8.
Water Scarcity and Conservation of Water
61-68
9.
Safe Handling and Storage of Water
69-75
Water Pollution
76-82
10.
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MY BODY
1
In our previous class, we have studied about the different sense organs of our body—
tongue, ears, skin, nose and eyes. All these parts can be seen from outside and are
known as external organs. There are several body parts which are present inside our
body and cannot be seen from outside. Such parts are called internal organs.
Name some internal organs.
Our body is a very complex system. It
works like a machine with the help of various
organs present in it. The organs form different
systems. One such system is the digestive
system. The mouth, food pipe, stomach and
intestines are the different organs that make
up the digestive system.
Digestive System
What happens to the food that we eat? The
food contains carbohydrates, proteins, fats
and other nutrients. These are complex
materials and are broken down into simpler
forms in our digestive system. This process
is called digestion.
Let us see how our mouth, which is the first part of our digestive system, helps
in the process of digestion.
Mouth
Ask your friend to open his/her mouth and observe it carefully. You will be able to
see different types of teeth and a tongue in the mouth.
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Teeth
Teeth are a very important part of our mouth. Teeth help to bite and chew the food.
They also give shape to our face and help us to speak clearly.
Two Sets of Teeth
A baby is born with no teeth. When the baby is about six months old, his/her teeth
begin to appear. By the time the baby is three years old, he/she has a set of twenty
teeth. These are temporary and are called the milk teeth.
Between the age of six and twelve years, the milk teeth fall out one by one and
new ones grow in their place. These new teeth are called permanent teeth. They
are thirty two in number.
Types of Teeth
1. Flat teeth: The teeth,
in the front of the mouth, are
flat and are used for biting and
cutting the food. They are known
as incisors. There are four
incisors in the upper jaw and
four incisors in the lower jaw.
2. Pointed teeth: On either
side of flat teeth is a sharp
pointed tooth. They are used for
tearing the food. They are known
as canines. There are four canines in all.
3. Broad and Grooved teeth: The teeth, present at the back of the mouth, are
broad and have grooves in them. They are used for chewing and grinding the food.
They are known as premolars and molars. There are eight premolars in all—four
in the upper jaw and four in the lower jaw. They are next to the canines. The molars
come after the premolars. There are twelve molars in all—six in the upper jaw and
six in the lower jaw.
Activity:
Count the number of teeth in your mouth and those of your parents and grandparents.
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Care of Teeth
Our teeth are very important to us. We must take care of them. If we do not take
care of our teeth, they can decay and fall.
Ways to Protect Teeth
1.Brush your teeth twice a day—in the morning and at night.
2.Rinse or wash your mouth after every meal.
3.Avoid eating sweets or sugary snacks and taking soft drinks as much as
possible.
4.Visit a dentist for regular dental check ups.
5.Eat fruits, like apple and guava, and vegetables, like radish and carrot. Such
foods give exercise to our gums.
6.Clean the tongue to remove germs.
7.Eat calcium rich food, like eggs, milk and milk products, for strong teeth.
The correct way of brushing teeth is shown through the the following illustrations:
Brush up and
Then brush up and
Always brush the teeth
down in front down the back
with a circular movement
xxIf sugar and bacteria are left on the teeth for long, they can cause tooth decay.
xxThe white outer covering of teeth is called enamel. This is the hardest substance in
the human body.
Tongue
Tongue is a soft, movable part inside our mouth. It is used for tasting, licking and
speaking. It also pushes the food into the food pipe at the time of swallowing.
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The back of the tongue is sensitive to bitter taste.
Its sides are sensitive to sour and salty tastes. The
tip of the tongue picks up sweet taste.
Along with the teeth and tongue, there are
three pairs of salivary glands present in the
mouth. These glands secrete saliva.
Digestion of food begins when we put the food in our mouth. Teeth help in
breaking the food into smaller pieces and chewing it. Here the saliva gets mixed with
the food and makes it soft. Saliva converts insoluble starch into soluble sugar. You
must have noticed that when you chew chappati for a longer time, it starts tasting
a little sweet. This is due to the action of saliva on our food. It is very important to
chew the food properly for proper digestion of food.
Stomach
From the mouth, the food goes into the food pipe and enters the stomach. The
stomach is a muscular bag-like organ in which food can be stored for a few hours.
During this time the food mixes with digestive juices secreted by the walls of the
stomach. The food is partially digested here.
Small Intestine
From the stomach the food is passed into a long and coiled structure called the
small intestine. The small intestine, the liver and the pancreas produce some more
digestive juices. Liver and pancreas pour
their juices into the small intestine. These
The liver is the largest gland of our body.
juices then get mixed with the food and
completely digest it in the small intestine.
The walls of the small intestine absorb the digested food and pass it to blood.
Blood carries the digested food to all parts of the body.
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Large Intestine
The undigested food passes into the large
intestine. The walls of the large intestine
absorb water from it and then pass it to
blood. The undigested semi-solid waste is
collected in the rectum and is eliminated
through the anus.
The length of the small intestine is
approximately 7 metres whereas the large
intestine is only 1.5 metres long.
While eating food, it is very essential
to see what should be eaten and how it
should be eaten.
One should:
1. wash hands before eating.
2. chew food properly before swallowing.
3. not speak while chewing food.
4. e
at green vegetables and fruits
everyday.
5. eat a balanced diet.
6. take food at fixed intervals.
7. d
rink about 8-10 glasses of water
everyday.
Importance
of
Cooking makes food soft, tasty and
digestible. It kills germs that may be
present in the food.
Eating Fresh, Clean Food
We eat raw as well as cooked food. Let us see
how cooked as well as uncooked food can
become the source of many infections.
)) Unwashed fruits and vegetables can
carry germs of diseases which can cause
diarrhea, vomiting and other stomach
ailments.
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)) Unwashed fruits and vegetables can also carry eggs of worms. These
eggs are too small to be seen by the naked eyes. When these eggs
reach the stomach of a human being, they hatch there and produce
worms. These worms live in stomach and intestines and consume the
food that is meant for the human body. People, having worms, generally
look weak, pale and unhealthy.
)) Peeled and cut fruits and vegetables, which
are exposed to flies and dust, can transfer
germs into the body and thus, cause many
diseases such as jaundice, cholera, etc.
)) Cooked food when left uncovered or unrefrigerated for long, can also
cause food poisoning. This happens because germs then get plenty
of time to grow and multiply in the food. The germs produce harmful
substances, which can cause vomiting and diarrhea.
It is very important that a person, suffering from diarrhea and vomiting, should be given
plenty of (cooled) boiled water containing a small amount of sugar and salt.
Keywords
canines
the four pointed teeth in our mouth.
diarrhea
a problem (an ailment) in which body tends
to lose too much of water through stools.
digestion
the process of breaking down of food into
simpler forms.
digestive juices
juices which help in digestion of food.
incisors
the flat teeth in the front of the mouth.
internal organs
organs present inside our body.
molars & premolars
the broad and grooved teeth present at the
back of the mouth.
saliva a liquid secreted in our mouth by the salivary
glands.
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Something to Know
A. Fill in the blanks.
1. The body organs that cannot be seen from outside are called
organs.
2.Flat teeth are in the
3.Tongue is used for
4.Saliva is secreted by
5.Flies can transfer
of the mouth.
and
.
.
to uncovered food.
B. Match the following:
1.milk teeth
(a) absorption of water
2.large intestine
(b) absorption of digested food
3.permanent teeth
(c) undigested waste is collected
4.
rectum(d) thirty two
5.
small intestine(e) twenty
C. Tick () the correct option.
1.The teeth, used to tear food into pieces, are known as—
(a) incisors
(b)canines
(c)molars
(d)premolars
2.Ria’s mother is thirty two years old. She is likely to have—
(a) 20 permanent teeth
(b)20 temporary teeth
(c) 32 permanent teeth
(d)32 temporary teeth
3.The organ, which secretes digestive juices in the small intestine, is the—
(a) liver
(b)salivary glands
(c) stomach
(d)food pipe
4.The food gets completely digested in the—
(a)mouth
(b)stomach
(c) small intestine
(d)large intestine
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5.An eight year old child is likely to have—
(a) only temporary teeth
(b)only permanent teeth
(c) both temporary and permanent teeth
(d) no teeth at all
D. Answer the following questions in brief.
1.Name the organ through which food enters the stomach.
2.How many sets of teeth are formed during one’s life time? Name them.
3.Write any one difference between milk teeth and permanent teeth.
4.What do you mean by the term ‘digestion’?
5.What happens to the food when it enters the stomach?
E. Answer the following questions.
1. List five good habits that should be taken care of at the time of eating
food.
2.Name the different types of teeth present in the mouth. Also mention
their functions.
3.Why is it important to chew the food properly?
4.Why is washing of fruits and vegetables important for us?
5.Sheena’s mother often tells her not to eat too many sweets and chocolates.
Why do you think she says so?
6.Complete the given foodpath:
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It was lunch time in the school. Rahul and his friends gathered to have lunch together.
All the friends started eating their lunch. Rahul did not find his lunch box in his bag.
He had forgotten it at home. His friend Sanyam noticed this. He immediately offered
to share his lunch with him. Rahul, however, moved out of the class. He bought
some food from the vendor outside the school gate and ate it.
.
1.What would you do if you were in Rahul’s place?
2.Sanyam tried to share his food with Rahul? In what situations do you share/
help your friends?
3.Do you think that eating food from roadside vendors is a healthy option?
Something to Do
1.Denture Making
Take some playing dough (clay) and a few peeled peanuts. Roll the clay
into the shape of jaw ( ) and place the peanuts the way your teeth are
arranged on the jaws.
Colour the flat teeth, pointed teeth and broad and grooved teeth in different
colours. Do not forget to give proper shape to the peanuts.
2.Visit the following websites for more information on the digestive system:
(a) www.makemeagenius.org
(b) www.scienceforkids.org
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MY
PLANTS
BODY
1
2
In Class-III, we learnt a little bit about plants. Let us revise the same by
completing the following statements:
Help Box
chlorophyll, stem, seeds, root
(a)
soil.
fixes a plant in the
(b)
supports a plant and
keeps it upright.
(c) Leaf has
in it to prepare
food and to give it its green colour.
(d) Fruits have
in them which germinate to form plants.
We know that a plant has different parts like root, stem, branches, leaves,
flowers and fruits. We have learnt about the leaf in some detail in the previous class.
Now, we will learn about the root of the plant.
The Root
It is an underground part of the plant. As the plant grows, its roots become thick and
woody with a corky outer layer.
Types of root
Roots are of two types:
)) Tap roots
)) Fibrous roots
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Tap root is a single, long root
with thin roots arising from it. Plants,
like beans, rose, lady finger, and
trees, like neem and peepal, have
tap roots.
Fibrous roots are those in which
many roots arise from the base of the
stem. A fibrous root tends to taper
downwards.
Fibrous roots are found in all
cereals, grasses and banana.
Roots help in soil conservation. They help to bind the soil and protect it from getting
washed away.
Functions of the root
Root is an important part of a plant. It helps the plant to absorb water and
minerals from the soil. It holds the plant upright in the soil. Thus, absorption and
fixation are the two main functions of roots. In some plants, roots perform a few
special functions.
)) Plants, like radish, carrot and
beetroot, have thick roots which
store food for the plant. Some
such roots are eaten by man and
animals. Such roots are called
edible roots.
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Edible roots, like carrot, radish, beetroot
are delicious and nutritious and add variety
to the diet.
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)) In some plants roots provide extra support to the plant. For example,
the branches of a banyan tree get extra support with the help of special
roots that grow downwards from the branches. Similarly, some plants,
like maize, have thin and long stems which require extra support to
keep them erect. Such plants have roots, arising from the base of their
stem, that help to support the plant.
In mangrove plants, roots do not
get sufficient oxygen in the marshy
areas. In such plants, some breathing
roots come out of the soil to get fresh
air from the atmosphere. Such roots,
found in banyan, maize and mangrove
plants, are called aerial roots.
There is a law against cutting trees. For cutting
down, or pruning, any tree, a written permission
from the appropriate authorities is required.
Keywords

atmosphere the air surrounding the earth.
erectupright.
germinate
to grow a sprout.
tapers
narrows and gets directed towards a point.
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Something to Know
A. Fill in the blanks.
1.
is the underground part of a plant.
2.Roots absorb
and
for the plant.
3.
Neem and peepal have
4.
roots.
and
are edible roots.
5.Mangrove plants have
roots.
B. Write True or False for the following statements.
1.Carrot and beetroot store food in them.
2. Beans and rose have fibrous roots.
3.All roots are edible.
4. Roots do not get sufficient oxygen in marshy areas.
C. Tick () the correct option.
1.The root of this plant stores food—
(a) mango
(c)banana
(d)carrot
(c)wheat
(d)rose
2.This plant has a tap root—
(a) banana
(b)apple
(b)grass
3.These plants have breathing roots—
(a)mangrove
(c)neem(d)
peepal
(b)apple
D. Answer the following questions in brief.
1.Name the two different types of roots.
2. Give two examples of plants having fibrous roots.
3.Why do aerial roots need to come out of the soil?
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E. Answer the following questions.
1. Draw the shape of the tap root and the fibrous root.
2. In what way(s) is the tap root different from the fibrous root?
3.State the two main functions of roots.
4.In what way are the roots of banyan tree and maize ‘special’?
Rohan saw Ram Manohar, the watchman, cutting a small tree to make a fire to
warm himself. He immediately asked him not to do so. Later, he went home and
requested his mother to give a blanket to the watchman. The watchman was very
happy to get the blanket. He thanked Rohan and promised him that he would not
cut any tree. He also promised to check that nobody else does so.
1.What does the above situation tell us about Rohan?
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2.How did he help the watchman?
3.Rohan, stopped the watchman from cutting trees. Have you ever done
anything similar to save your environment?
Something to Do
1.Take a small sapling of grass and a mustard plant, observe their roots and
note down their differences, if any.
2.Prepare a chart showing some ‘edible roots’. List down the ways in which
they are usually eaten.
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2
3
FLOWERS ANDPLANTS
FRUITS
Flower is a colourful and beautiful part of a
plant. It generally has a pleasant fragrance. Most
flowers have attractive colours. Some flowers do
not have attractive colours but have very pleasant
fragrance. For example, champa, motia and
chameli are some of such fragrant flowers.
A flower develops from a bud. The buds of
different flowers vary in their size and shape. The
bud of a plant is generally covered with green leaves. These leaves protect the bud
and help it to bloom into a flower.
Buds of different flowers
Flowers have different shapes and sizes. Some flowers are like a bell, some
are like a plate or a bowl and some are like a brush. Some flowers bloom singly
whereas others bloom in bunches.
Flowers make fruits. Most of the fruits bear seeds. These seeds, in turn, can
grow into more plants.
Activity:
Observe any bud. Find, and write, two differences between a bud and a flower.
1. ___________________________________________________________________________________
2. ___________________________________________________________________________________
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Seasonal Flowers
We see different flowers in different seasons. In summer, you must have seen
chameli, motia, sada-bahar, china rose and lily flowers blooming in gardens. In
winter, dahlia, rose and chrysanthmum are some of the commonly seen flowers.
Chameli
China rose
Lily
Sada-bahar
Summer flowers
Dahlia
Rose
Winter flowers
Watermeal, or Wolffia Globosa, is the smallest flower and Rafflesia Arnoldi is the largest
flower in the world.
Uses
of
Flowers
In our day-to-day life, we use flowers in different ways:
)) Some flowers have a very pleasant fragrance. These are used for making
perfumes. Rose, jasmine, keora and lavender are some of such flowers.
)) Some flowers can be cooked and eaten like a vegetable. Kachnar, banana
and sahjan flowers are eaten as vegetables in many parts of India.
Keora
Lavender
Banana
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Kachnar
Sahjan
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)) Some flowers are used as medicines. Cloves are the dried flower
buds from the clove plants. The oil, extracted from cloves, is used as
a medicine. Similarly, lotion made from arnica flower, is used to cure
wounds and injuries. Rose water is used as a medicine and also for
adding flavour to sweets and drinks.
)) Flowers, are also used in preparing
cosmetics.
)) Flowers, like marigold and zenia are
used for making colours. These colours
are then used to dye clothes.
)) Flowers are often used for decoration
Marigold
Zenia
purposes.
Activity:
(a)
Ask your mother whether she uses flowers as vegetables. If yes, note down the names of
such flowers.
1. _________________ 2. _________________ 3. _________________ 4. _________________
(b) Write down a few places where you have seen flowers used as a decorative material.
1. _________________ 2. _________________ 3. _________________ 4. _________________
Activity:
Have you ever visited a florist? There, one can see many types of flower arrangements in bouquets.
Visit a florist and gather the necessary information to do the following task.
(a)Write the names of any two flowers available with the florist.
1. __________________________
2. __________________________
(b)Name any two types of flowers which remain in great demand throughout the year.
1. __________________________
2. __________________________
(c)Where does the florist bring these flowers from?
_________________________________________________________________________________
(d)List down the different types of materials used by the florist for making bouquets.
_________________________________________________________________________________
(e)Why do people buy bouquets?
_________________________________________________________________________________
We have now learnt that flowers are used to prepare medicines, perfumes and
scents. These can also be used as decorative material. It is important, therefore, to
protect flowers from being plucked unnecessarily.
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Fruits
We have already read that flowers make fruits. Fruits usually store seeds and food
in them. We eat fruits because they give nutrition to our body. Fruits generally have
good taste and flavour.
Fruits generally have seeds which produce new plants. Some fruits, like mango,
peach, plum have only one seed. Some
other fruits, like lemon, papaya, orange and
Banana has no seeds. It reproduces
watermelon, have very many seeds. Some
through its stem.
varieties of bananas, grapes and papayas do
not have any seeds in their fruits.
We get different types of fruits in different seasons. In summers we get fruits like
muskmelon, watermelon, mango, litchi, jamun and falsa. In winters, we get grapes,
apples, oranges and Indian gooseberry (amla). Such fruits are called seasonal
fruits.
Summer fruits
Winter fruits
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There are some fruits, like cashewnuts, almonds and
walnuts, which are first dried and then used. These dry
fruits are often eaten as such. They are also used in
preparing various dishes that are generally eaten during
the winter season.
Bitter gourd (karela), gourd, jack fruit (kathal), brinjal,
okra (bhindi) and tomato are some fruits which are
commonly used as vegetables.
Brinjal
Okra
Some fruits, like mango, lemon and
strawberries, are also used for preparing
pickles, chutneys and marmalades.
Dry fruits
Tomato
Jack fruit is the largest fruit in the world.
Fruit chutney
Fruit jam
Thus, fruits are very useful for all of us.
Keywords

extract
to take out.
fragrance
sweet smell.
generallyusually.
prepare
to make.
variety
different types.
wound
when some part of the body gets hurt.
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Something to Know
A. Fill in the blanks.
1.Flower is the colourful part of a
.
2. A flower develops from a
3. Oil, extracted from cloves, is used as a
4. We must protect flowers from being
5.Dry fruits are generally eaten in
.
.
unnecessarily.
season.
B. Write True or False for the following statements.
1. A bud is covered with green leaves.
2. All flowers look alike.
3. Lavender is cooked and eaten as a vegetable.
4. Fruits make flowers.
5. Jackfruit and tomato are fruits that are often used as vegetables.
C. Tick () the correct option.
1. It blooms in summer—
(d) chrysanthmum (c) rose
(a) zenia
(b) marigold
(c) arnica
(d) banana
(c) plum
(d) watermelon
3. It has many seeds—
(b) dahlia
2. It is useful for curing wounds and injuries—
(a) motia
(a) mango
(b) peach
4. It is generally not used for preparing jams—
(a) apple
(b) bitter gourd
D. Answer the following questions in brief.
1. State any two uses of flowers.
2. How do green leaves help a bud?
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(c) strawberry
(d) orange
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3. Name two flowers which are eaten as vegetables.
4. Name any three dry fruits. Write two ways in which they are used in
our daily life.
E. Answer the following questions.
1. Write five lines about flowers.
2. What do you understand by ‘seasonal flowers’? Give two examples of
seasonal flowers.
3.Write any two uses of fruits.
4. List the food preparations that can be made by using mango fruit.
Rita wanted to pluck flowers from the nearby garden. Her mother objected to it and
said that we should take care of flowers and not pluck them. While going home,
Rita’s mother bought a bouquet from a young boy who was selling flowers. She told
Rita that the flowers, the boy was selling, were cultivated for selling purpose only
and the money which he will get, will help him to feed his family.
1. Why did Rita’s mother object to the plucking of flowers?
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2. What does the above situation tell us about Rita’s mother?
3. Suggest some ways to help the needy.
Something to Do
1. Collect the flowers that have fallen down from plants and bring them to
your class. Observe their structure.
2. Use dried flowers and leaves to make greeting cards.
3. Discuss, in class, why we should not pluck flowers just for fun.
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