IV CLASS - SCIENCE

Class : IV (2009 – 2010) Term – I Sub : Science
PLANT LIFE

New Words:
Fibrous roots, Tropism, Absorption, Conduction, Stomata, Chlorophyll, Photosynthesis, Respiration, Transpiration, Reproduction, Transplantation, Dispersal, Explosion.

Answer the following :

1. What are the different parts of the plant?
A A plant has two main parts – root system and shoot system.

2. Name the two types of roots.
A. The two types of roots are – a) Fibrous roots. Eg: grass, maize, wheat, etc and b) Tap
root. Eg: carrot, radish, mango, neem, etc.

3. Define Hydrotropism.
A. The movement of the roots and root hairs towards water is called hydrotropism.

4. Define geotropism .
A. Geotropism – The movement of the roots of a plant towards the centre of the earth, due to
gravitational pull of the earth is called geotropism.

5. Give important functions of the root.
A. The main functions of the roots are :
i) Fixation : It helps to hold the plant firmly in the soil.
ii) Absorption – Root hairs absorb water and mineral salts from the soil.
iii) Conduction – The root conducts water from the soil to the leaves through the stem.
iv) Storage – The root stores excess food prepared by the leaves.

6.Give a reason for the following – roots grow downwards in the soil and shoot grows
upwards above the soil.
A. Roots grow downwards in the soil to absorb the water and minerals from the soil and shoots grow
upwards above the soil to trap sun light by the leaves for the process of photosynthesis.

7. Give two examples for plant that store excess food in their roots.
A. Carrot and Beetroot.

8. Give two examples for plants that store excess food in their stem.
A. Sugar cane, Potato.

9. Define stomata.
A. Stomata are tiny holes present on the leaves which helps the plants in breathing.

10. Which part of the plant is called ‘ the kitchen of the plant’?
A. Leaf is called ‘the kitchen of the plant’.

10. Define photosynthesis.
A. The process in which leaves of a green plant prepare food by using water,
Carbon dioxide and minerals in the presence of sunlight is called photosynthesis. A green coloured substance (pigment) called chlorophyll is required for the process.

11. Give two examples of plants that store excess food in their leaves.
A. Spinach and cabbage store excess food in their leaves.

12. Why leaves are called ‘kitchen of the plant’ ?
A. Leaves contain chlorophyll which traps sun light and with the help of water and carbon dioxide makes its own food. Hence, leaves are called ‘kitchen of the plant’.

13. How are the seeds dispersed by wind?
A. Some seeds and fruits have hair on them that makes it easy to be carried away by wind.

14. Give two ways in which animals help in dispersal of seeds .
i) Animals eat fruits along with the seeds and excrete the seeds as waste product from their bodies at a different place.
ii) Seeds and fruits with hooks and thorns get stuck to the bodies of animals and get carried to distant places.

15. Give reason for the following. The seeds of plants are scattered by dispersal.
A. Seeds should be scattered far and wide – other wise they grow in one place. In that case, only a few seeds will germinate and the rest will die due to lack of food, water and sunlight.

Answers for the Reader exercises :

Give two examples for the following :

a) spinach and cabbage
b) carrot and beetroot
c) ginger and potato

Fill in the blanks :
a) root
b) minerals and water
c) water
d) sunlight
e) firmly
f) water
g) agents
h) dry

Choose the correct answer:
a) root
b) oxygen
c) phototropism
d) water
e) dispersal

True or False:
a) False
b) True
c) True
d) False
e) True
f) False
g) True

Draw a neat labeled diagram of a plant.


Ls. 2 Uses of plants

New Words :

Vitamins, Carbohydrates, Beverages, Proteins, Minerals, Cereals, Pulses, Eucalyptus, Fodder, Conservation.

Question and Answers :

1.Name different food materials that we obtain from plants.
A. Vegetables, fruits, cereals, pulses, nuts, beverages, spices, oils and sugar are some examples of foods that we get from plants.

2. Give any 6 uses of plants.
A.
a) Plants provide us oxygen.
b) They give us food.
c) They give us medicines.
d) They help to conserve soil.
e) They give us fibre to make clothes.
f) Plants provide shelter to us.


Answers for reader exercises :

1. Fill in the blanks :
a) medicinal b) flax c) beverages d) teak, rosewood e) oxygen

2. True or false :
a) True b) False c) False d) False e) False

3. Match the following :

a) rice, wheat, maize b) Bengal gram, green gram c) cardamom, pepper, cloves
d) coffee, tea, cocoa e) grapes, apple, mango

4. Give two examples of the following :

a) banyan, peepal b) cotton, flax c) mustard, groundnut
d) sugar cane, beetroot e) jasmine, rose f) cactus, crotons g) neem, tulsi






Ls. 3 – Animal Life

New Words :

Domestic, Nutrients, Poultry, Ornaments, Oysters, Endangered, Luxury, Roosters, Proteins, Minerals, Leather, Tannery.

Question and Answers :

1. Describe how animals are useful to us.
A. Animals are useful to us in the following ways:
(i) Animals give us food such as milk, eggs, meat, etc.
(ii) They help in carrying loads and in transportation.
(iii) Animals give us clothing such as wool and silk.
(iv) They guard our homes and help us in farms.
(v) Animal waste can be used as fuel.
(vi) We can make leather and ornaments from the body parts of animals.

2. Define ‘beast of burden’.
A. Animals that help in carrying loads are called ‘beasts of burden’. Ex. Horses, donkeys & bullocks.


3. What do we get from the horns of animals.
A. People make ornaments and musical instruments from the horns of animals.

Answers for reader exercises:

Fill in the blanks :

1. wool 2. Leather 3. Poultry 4. Cow dung
5. pearls 6. Ivory 7. Earthworm

Match the following :

1. bulls 2. Elephant 3. Brush 4. Wool 5. Leather
6. manure 7. Poultry 8. Buggy

True or False :

1. True 2. False 3. True 4. False 5. True 6. True

Choose the correct answer :

1. ox 2. Elephant 3. Cowdung 4) eggs

Who am I ?

1) Snake 2) Cow 3) Camel 4) Elephant 5) Silkworm

Give examples of the following :

a) Goat b) Hen c) Donkey d) Bullock

Answer in one word :

a) Honey Bee b) Sheep


Ls. 4 – Care and Protection of Domestic Animals

New words :

veterinarian, coops, turkeys, stables, shelter, poultry.

Question and Answers :

1. What kind of food should we give to farm animals?
A. We should give healthy and clean food and water to farm animals. They should be given energy-giving foods like oil seeds, grains, etc.

2. What kind of food should we give to milk-giving animals?
A. We should give good, healthy food like green grass and cotton seeds to milk-giving animals.

3. How should animal shelters be kept?
A. Animal shelter should be kept clean, dry and airy. We have to make sure that these shelters receive bright sunlight and are free from flies and mosquitoes.

4. How should we take care of farm animals?
A.
(i) Farm animals should be kept in special homes.
(ii) Animal homes must be washed and waste materials cleaned everyday.
(iii) They should be given healthy and energy-giving foods.
(iv) They should be given clean drinking water.

Answer for reader exercises :

Fill in the blanks :

a) domestic b) bath c) veterinarian d) eggs, meat

Choose the correct answer :

a) cat b) farm birds c) tusk d) horses e) cattle

Match the following :

a) kennel b) sty c) stable d) shed e) coop f) cage



Ls. 5 – Natural Resources

New Words:

resources, replenishing, renewable, depleted, conservation, fertilisers, deforestation, prohibited, sanctuaries, sustaining.

Question and Answers :

1. Define renewable and non-renewable resources.
A.
Some resources such as water, wind, trees, etc., which nature keeps producing and replenishing are called renewable resources.
Some resources which do not have end less supply such as natural gas, minerals, coal and petroleum are called non-renewable resources.

2. Explain soil conservation.
A. The roots of plants hold the soil together so that the fertile part of the topsoil doesn’t get washed away with heavy rains. So, the prevention of soil erosion by planting more trees is known as conservation of soil.

3. Why are forests so important to us?
A. Forests give us pure air to breathe in and bring rainfall which helps to grow new plants. Forests are the home for many animals. Plants give us food and prevent soil erosion.

4. What did the people of the Chipko Movement do?
A. The people of the Chipko Movement hugged trees to protect them from people who wanted to cut them.

5. How can we help to save our forests?
A. We can help save our forests by:
(i) Planting more trees
(ii) Preventing forest fires.
(iii) Teaching people about the importance of forests.
(iv) Avoid cutting and uprooting of trees for domestic purposes.

6. What is deforestation?
A. Thoughtless cutting down of forests by human beings for their selfish needs is called deforestation.

7. Why should we help to protect wildlife?
A. We should protect wildlife as they help to maintain the balance of the environment. Disturbing this balance will affect the existence of all creatures including human beings.

Fill in the blanks :

a) animals b) Uttaranchal c) lungs, living d) Gujarat
e) deforestation f) Plants g) Wildlife h) Non-renewable
i) elephants j) Chital; black buck

Choose the correct answer :

a) Preserving b) Vanmahotsav c) crocodile d) forbidden


True or False :

a) False b) True c) True d) False

Match the following :

a) Mudumalai b) Annamalai c) Corbett Park d) Gir forest

6. Our internal organs

New Words :

Skeleton, Interlocked, Kidneys, Transported, Urinary bladder, Carbondioxide, Muscles, Ribcage.

Question and Answers :

1. What are internal organs?
A. The organs which are present inside our body are called internal organs. Ex. Heart, lungs, brain etc.

Question and answers :

2. Describe the function of lungs.
A. The lungs absorb the oxygen in the air and supply it to the blood. The blood carries oxygen to all parts of the body. Thus, the lungs help to purify blood.

3. How does the heart helps us?
A. The heart helps us by pumping blood to different parts of the body.

4. Describe the function of kidneys.
A. The kidneys are a pair of bean-shaped organs which help to remove the liquid waste products from the body. The blood carries waste material to the kidneys. The liquid waste is then transported to the urinary bladder by the kidneys. Then, this liquid waste is excreted in the form of urine.

Draw a neat labeled diagram of a kidney and lungs.

7. Food and Digestion

New Words :

Diseases, Nutrients, Proteins, Minerals, Vitamins, Carbohydrates, Roughage, Deficiency, Malnutrition, Kwashiorkor, Marasmus, Anaemia, Goitre, Scurvy, Rickets, Beri Beri, Pasteurisation, Canning, Faeces, Expelled.


Question and Answers :

1. Why do all living things need food?
A. Food gives us energy. All living things need food to grow, remain healthy, fight diseases and carry out biological activities.

2. Name the different types of nutrients present in food.
A. The five major nutrients present in food are carbohydrates, proteins, fats, vitamins and minerals.

3. Why should we take carbohydrates and fats?
A. We should take carbohydrates and fats as they are energy-giving nutrients and provide us energy to work.

4. What is a balanced diet?
A. A diet which contains energy-giving nutrients, body-building nutrients and protective nutrients in the appropriate quantities and in accordance with the needs of the body is called a balanced diet.

5. Why should we include roughage in our food?
A. Roughage is the undigested part of food and is needed for the excretion of waste products from our body after the food is digested.

6. Name the three categories of deficiency diseases.
A. Deficiency diseases can be divided into three broad categories;
a) Protein Calorie Malnutrition
b) Mineral deficiency and
c) Vitamin Deficiency

7. Define Micro-organisms.
A. Organisms which are very small and can be seen only under a micro-scope are called micro-organisms. Eg: Bacteria, virus, protozoa, etc

8. Describe different ways of preserving food.
A. The different ways of preserving food are :
1. cooking 2. Boiling
3. salting 4. Sweetening
5. drying and dehydrating 6. Pickling
7. freezing 8. Canning
9. cold storage 10. Dry storage
11. pasteurisation

9. Explain the term digestion of food.
A. The food that we eat is broken down into small pieces that dissolve and are absorbed by our blood. This process is called digestion.

Answer for reader exercises :

Give three examples for each of the following :

a) Meat, pulses, milk b) Cheese, butter, nuts c) Soyabean, fish, eggs
d) Milk, eggs, carrots


Fill in the blanks :

a) Vitamins, minerals, b) Proteins c) Animal fat, vegetable fat
d) work, play e) Sugar, potato f) Bacteria
g) Pasteurisation

Give reasons for the following statements :
a) A balanced diet provides all the five nutrients, namely vitamins, minerals, carbohydrates, proteins and fats in the appropriate quantities and in accordance with the needs of the body. A balanced diet helps us to grow and protects our body against diseases.
b) Food should not be left uncovered as microbes can grow in the food and spoil it.
c) Milk is considered a complete food as it contains all the five nutrients required by the body for energy and growth.

True or False :
a) False b) True c) True d) False e) True

Match the following :
a) starchy vegetables b) proteins c) vitamins and minerals
d) milk e) fibre
Choose the correct answer :
a) energy-giving b) Vitamins c) diet

Deficiency Diseases :
Protein Calorie Malnutrition – Kwashiorkor, Marasmus.

Mineral Deficiency :
Iron – anaemia
Calcium – Weak bones
Iodine – Goitre
Fluorine – Decaying of teeth

Vitamin Deficiency :

Vitamin A – Night Blindness
Vitamin B – Beri Beri
Vitamin C – Scurvy
Vitamin D - Rickets

8. Disease and Sanitation


New Words :

Communicable, Diseases, Microscope, Micro Organisms, Diagnosis, Tuberculosis, Diphtheria, Measles, Pneumonia, Whooping cough, Influenza, Contaminates, Jaundice, Scabies, Leprosy, Malaria, Tetanus, Parasites, Disinfectants, Dysentery.

Question and Answers :

1. What do you mean by communicable diseases?
a. Diseases that easily spread from one person to another through various mediums like Air, Water, Food, Insects are called communicable diseases.

2. What is hygiene?
A. The practice of keeping ourselves and our surroundings clean is called hygiene.

3. How can we keep the water pure and clean?
A. We can keep drinking water pure and clean by using clean vessels for storing water and keeping these vessels covered. The water should be boiled and filtered.

4. How do flies spread diseases?
A. Flies normally sit on rubbish heaps and garbage dumps and pick up germs in the process. When these flies sit on our food and water, these germs are transferred to the food and enter the body. They start to multiply in our stomach and intestine and cause diseases.

5. How can we prevent the spreading of diseases?
A. We can prevent the spreading of diseases from a sick person by taking the following steps:
(i) The sick person should be isolated as far as possible.
(ii) Personal articles of the sick person should be washed and disinfected properly.
(iii) The room occupied by the patient should be aired and exposed to sunlight.
(iv) The bed linen of the sick person should be cleaned regularly.

Answers for reader exercises :

Fill in the blanks :

a) water b) garbage c) pure, clean d) communicable diseases
d) boiled, filtered

Choose the correct answer :

a) in closed dustbins b) made into compost c) insecticides
d) covered e) germs



Class IV Term II Science

Lesson No. 1
WATER

New words.

1) essential
2) source
3) polluted
4) sewage
5) irrigation
6) quenches
7) refining
ultra violet light

Questions and Answers :

Q1. Why can’t we drink sea water?
A. We cannot drink sea water as it is too salty.

Q2. Write a short note on underground water and how it is used for irrigation?
A. Some rain water seeps underground through the soil and gets collected there. This water gets filtered naturally when it passes through the layers of soil, topsoil, subsoil and porous rocks. The underground water can be drawn in large amounts by tube wells that run on electricity. This water is used for irrigation.

Q3. What are the uses of water?
A. Water has many uses. Some of these are :
a) We drink water. It helps in the digestion of food and excretion of waste materials from the body in the form of urine and sweat.
b) Water is used for bathing, washing, cooking etc.
c) It is used in factories.
d) It is an important mode of transport.
e) It is used for putting out fires.
f) Water is also used by plants and animals.

Q4. Describe four ways to reduce water pollution.
A. Four ways to reduce water pollution are –
a) Factories should be away from residential areas. They should treat chemical wastes before letting them out into water bodies.
b) Farmers should reduce the use of chemical pesticides.
c) Drinking water pipes and sewage pipes should not be laid side by side.
d) Wells should be kept covered.

Q5. How can we save water?
A. We can save water by-
a) Keeping the tap closed while brushing teeth or washing face.
b) Water used for washing fruits and vegetables can be reused for watering the plants.
c) By storing rain water.

Answers for Reader Exercises :
Fill in the blanks :

a) 75%
b) Blue planet
c) Salt water
d) Electric pumps, tube wells, hand pumps
e) Germs, cholera, typhoid

State ‘True’ or ‘False’ :

a) F b) F c) F d) F e) F

Choose the correct answer :
a) saltwater b) sulphur c) pesticides d) boiling
e) sewage f) clean

Match the following :

a) underground water
b) rainwater harvesting
c) kills germs in water
d) water filter
e) draw up underground water

Ls. 2 – HEALTH AND HYGIENE

New words :
1) healthy
2) balanced diet
3) Posture
4) Stamina
5) Hygiene
6) Bruise
7) Plaque
8) Vaccine
9) Immunisation

Questions and Answers:

Q1. Why is it not good to eat food from hawkers?
A. It is not good to eat food from hawkers as they keep the food uncovered. This food may carry germs and can cause illness.

Q2. What is posture?
A. The position in which you hold your body when you stand, sit or move is called posture.

Q3. What is plaque? How does it harm teeth?
A. Plaque is a substance that forms on our teeth and in which bacteria can grow. Plaque can cause tooth decay and gum infection.

Q4. Describe four good food habits.
A. Four good food habits are –
a) Having a balanced diet.
b) Eating lots of fruits and vegetables.
c) Drinking plenty of water.
d) Avoiding too much fried food and cold drinks.

Reader exercises Answers : (pgs. 122 & 123)

Fill in the blanks :

a) balanced diet b) posture c) walking
d) pins, needles, match sticks e) Immunisation f) BCG



Write True or False :

a) F b) F c) T d) T e) F f) F


Choose the correct answer :

a) posture b) swimming c) tongue cleaner d) plaque
e) polio

Match the following :

a) exercises b) 7-8 hours a day c) immunisation
d) keeping our body and surroundings clean e) causes tooth decay

Give reasons for the following :

a) You should never miss breakfast – because it gives us energy to work and play for the entire day.
b) Television set must be kept at least six feet away from where we sit because watching television from too close can harm our eyes.
c) You should take necessary vaccines – because they help us to fight against diseases.


*** Ls. 3 PROTECTION OF PLANTS [Deleted]



*** Ls. 4 – PROTECTION OF ANIMALS
Deleted as most of the lesson is already covered in 1st Term



Ls. 5 - MATTER


New words –
Molecules, atoms, volume, transparent, opaque, conductor, non-conductor, solvent, solution, sedimentation, decantation, filtration, crystallisation.

Questions and Answers:

Q1. Define i) molecules ii) atom
A.
a) Molecules : matter is made up of tiny particles called molecules.
b) Atoms : A molecule is made up of smaller group of particles called atoms.

Q2. State three differences between a solid and a liquid.
A. Three differences between a solid and a liquid are

Solids
1) Molecules are closely packed.
2) They have a definite shape and volume.
3) Solids cannot flow.
Liquids
1) Molecules are not very closely packed.
2) They do not have a definite shape but have fixed volume.
3) Liquids can flow.

Q3. Define a) opaque objects b) transparent objects.
A.
a) Opaque objects : Materials that do not allow light to pass through them are called opaque objects. Ex. Wood, Cardboard etc.
b) Transparent objects : Materials that allow light to pass through them are called transparent objects. Ex. Glass, air etc.

Q4. Define conductors and non-conductors.
A.
a) Conductors : Materials that allow heat or electricity to pass through them are called conductors. Ex. Iron, copper.
b) Non-conductors : Materials that do not allow heat or electricity to pass through them are called non – conductors. Ex. Wood, rubber.

Activity : Activity 1, 2 & 3 on pg. No. 135 and 136. Give more examples of freezing / melting – Candle wax, coconut oil, ghee, butter etc.

Question and Answer :

Q5. Define the following.
A.
a) Freezing – The change of a substance from its liquid state to its solid state is called freezing.
b) Crystallisation : The process of forming crystals by heating the solution is called crystallisation.
c) Sedimentation : The process by which the particles of an insoluble substance settle down at the bottom of a liquid is known as sedimentation.
d) Decantation : The method of separating an insoluble solid from a liquid is called decantation.
e) Filtration : The method of purifying a liquid by filtering the solid out of the liquid with the help of a filter paper is called filtration.

Reader exercises.

Fill in the blanks :
a) molecules b) atoms c) solids, liquids and gases d) evaporation
a) sedimentation, decantation and filtration.

Write ‘True’ or ‘False’ :
a) T b) F c) F d) F e) T

Choose the correct answer :
a) attraction b) sedimentation c) crystallisation
d) definite e) non-conductors


Match the following :
a) has a definite shape and volume.
b) has a definite volume but indefinite shape
c) has no definite shape or volume
d) dissolves in a liquid completely
e) is the liquid in which a solid dissolves
f) is formed when a solute dissolves in a liquid completely.

Give reasons for the following :
a) There are three states of matter : solids, liquids and gases which depend upon the arrangement of molecules.
b) The smell of perfume spreads across the entire room as the molecules are very loosely bound and freely move in all the space available.
c) An iron rod gets heated up quickly when left in the sun because iron is a good conductor of heat.

Day – 8 – Draw a neat labeled diagram showing molecular arrangement in solids, liquids, gases.


Ls. 6 – SAFETY AND FIRST - AID

New words :
Accidents, injuries, scissors, gauze, antiseptic, ointment, wound, electricity, pedestrian, amber, brake.

Questions and Answers:

Q1. What is first-aid?
A. First-aid is the immediate medical treatment given to someone as soon as she or he is injured or falls ill.

Q2. What are the things that must be kept in a first-aid box?
A. A first-aid box must contain plasters, scissors, gauze, bandage, cotton wool, a disinfectant and anti-septic ointments.

Q3. What first-aid will you give a person who has had a minor cut?
A. The first-aid that we give a person who has a minor cut is :
a) We should wash our hands with soap and water before touching the wound.
b) Dry and clean the wound with a clean cloth or cotton.
c) Apply antiseptic cream on it and cover it with a band-aid.

Q4. What safety rules should you follow while crossing the road?
A. The safety rules to be followed while crossing the road are ;
a) Not to run across the road.
b) Cross the road only at the zebra crossing.
c) Walk on the pavement.
d) Cross the road only when the pedestrian light is green.

Answers for reader exercises :

Fill in the blanks :
a) accident b) first-aid c) cuts, wounds, burns
d) burns e) level crossing

State True or False :
a) F b) T c) F d) T e) F

Match the following :
a) use Dettol or Savlon
b) use burnol
c) turn off the main switch
d) tells us to stop
e) tells us to cross the road
* * *

TERM – III
Class: IV Sub: Science

Lesson – 1. AIR AND WATER

New words:
1. temperature 2. tilted 3. revolves 4. slanted

Question and answers: -

Q1. Why does one part of the earth has summer while the other part has winter?
Ans. The earth revolves around the sun with its axis tilted to one side. As the direct rays of the sun heat the earth more than the slanted rays, the part of the earth facing the sun will be warmer and have summer. The other part facing away from the sun will be colder and will have winter.
New Words:
1. absorb 2. pressure 3. creates

Question and answers:

Q1. What is sea breeze?
Ans. The movement of the air from sea to land during the day is called sea breeze.

Q2. What is land breeze?
Ans. The movement of air from land to sea is called land breeze.

New words:
1. condensation 2. evaporation 3. contact 4. repeated
5. dew 6. meteorology 7. forecast

Question and answers: -
Q4. Why does snow fall in very cold temperatures?
Ans. The clouds become very cold in places where the temperature is low. The water vapour in the clouds condense to form soft and fine particles of ice instead of water. This is snow.

Q5. How is dew formed?
Ans. The water vapour in the air condenses on leaves and grass to form drops of water. This is called dew.


Q6. What is water cycle?
Ans. The continuous and repeated change of water into water vapour and then again to water is called water cycle.

Q7. What is a weather forecast?
Ans. Weather forecast is a report prepared by a meteorologist predicting the weather conditions for a short period of time. It includes rain, storm, flood, snowfall etc.


Give reasons: - Assignment for Lesson – 1.

a. During the day land is warmer than the sea.
Ans. Land gets heated faster than sea. So, land is warmer during the day.

b. Sea breezes are formed during the day.
Ans. Sea breezes are formed because the land gets heated faster during the day, warm air rises up. To replace this air, cool air, from sea rushes towards land.

c. Sun plays an important role in causing changes in weather.
Ans. Sunlight is absorbed more by land than by sea there by showing a difference in temperatures. So the heating and cooling of land and sea create a difference in their temperatures and thereby causes changes in the weather conditions.

d. Dew drops form on surface of leaves during night.
Ans. At night the water vapour condenses on cool surfaces like grass and leaves to form dew drops.

e. Weather forecasts are useful for sailors, fishermen etc.
Ans. It is useful for sailors and fishermen because their work depends on weather conditions.

1. F / B
a. Rotation – day
b. weather
c. direct rays
d. summer
e. land / sea
f. land breeze
2. T / F
a. False
b. True
c. False
d. True
e. False
3. CTBA
a. water cycle
b. sea breeze
c. summer
d. cloud



4. a) water droplets formed on cold objects.
b) soft particles of ice that fall on earth.
c) formed when H2O vapour in air condenses into drops of water.
d) change of water vapour to water.
e) blows during day.

5. Draw a neat labeled diagram of water cycle.

Lesson – 2. EARTH AND SOIL
New words: -

1. weathering 2. humus 3. nutrients

Answer the following questions: -

Q1. What is soil?
Ans. The uppermost layer of the Earth’s surface is called soil. It is made up of rocks and minerals mixed with organic matter.

Q2. Why is soil important for plants?
Ans. Plants need soil to support themselves and to grow. They use different nutrients present in soil for their growth.

New words: -
1. property 3. retention
2. porosity 4. percolation

Give reasons: -

a. Extremely porous soil cannot retain water.
Ans. Porous soil has small spaces between them. This allows air and water to pass through it. If the spaces are too many, the soil cannot retain water.

Answer the following question: -
Q4. What is soil percolation?
Ans. The ability of the soil to absorb water is called soil percolation.

New words: -
1. alluvial 3. texture
2. laterite 4. volcano

Give reasons: -
b. Red soil is red in colour.
Ans. Red soil is red in colour due to the high content of iron in it.

c. Desert soil is not suitable to grow crops.
Ans. Desert soil has a sandy texture and high salt content which makes it unsuitable to grow crops.

d. Alluvial soil is the most suitable to grow crops.
Ans. Alluvial soil is made up of fine silt brought down by a river which is rich in minerals and is very fertile.

Answer the following questions: -
Q3. How is black soil formed?
Ans. Black soil is formed from volcanic rocks which are formed from lava that spurts out of a volcano.

Q4. Where is laterite soil found and what kinds of crops are grown in this soil?
Ans. Laterite soil is formed due to gradual weathering of rocks into smaller particles. It is found mostly on hills. Crops like tea, coffee, spices, coconut, cashew, eucalyptus grow well in this soil.

New words: -
1. manures 3. rotation
2. fertilizers 4. irrigation

Give reasons:
e. The farmer should grow groundnuts in a soil where cotton has been grown for some years.
Ans. The soil in which cotton is grown loses its nitrate content. Groundnuts are grown in soil where cotton is grown for some years to retrieve its nitrate content.

Answer the following questions: -
Q5. How should grains be stored?
Ans. 1. The grains should be dried well.
2. The store room for storing grains should be cleaned and sprayed with pesticides and insecticides.
3. The grains should be stored in gunny bags or air tight containers.

Q6. What is rotation of crops?
Ans. The method by which soil is kept healthy by growing different crops every year is called crop rotation.

F.I.B
a. soil
b. humus
c. grey or red
d. black
e. Mountain
f. irrigation

T / F
a. The soil is made fertile by adding the dead remains of plants and animals to it.
b. False
c. False
d. True
e. False
f. False
Choose the best answer.
a. weathering
b. humus
c. nutrients
d. rotation
e. humus


Match the following.

a. The two layers of soil
b. Two kinds of soil
c. Fertile matter brought down and deposited by rivers and streams
d. Artificial supply of water to the crops.
e. Allows air and water to pass through them
f. Sandy texture, high salt content, unsuitable for cultivation.

Draw a neat labeled diagram showing layers of soil.


Lesson – 3. ENERGY
Give reasons: -
Q1. We need food to live.
Ans. Food gives us energy: We need energy to perform various vital activities. Hence we need food to live.

Q2. A car needs fuel to run.
Ans. Heat energy is produced when fuel is burnt. Burning of fuel produces heat energy in a car which helps the car to run.

Q3. Sunlight is very important for plants.
Ans. Repeated in Q and Ans. could be deleted.

Question and answers: -
Q1. Name the various forms of energy?
Ans. Energy exists in many forms. Some forms of energy are heat energy, light energy, electric energy, mechanical energy, chemical energy etc.



Q2. How is light energy useful?
Ans. Plants use the energy present in the sunlight to make their own food by the process of photosynthesis.

Q3. Mention the importance of electrical energy in our day to day life.
Ans. Electrical energy is one of the most important forms of energy. It is used to run fans, coolers, bulbs, tubelights, electric geysers, washing machines, A.C’s and other electrical appliances.

Give reasons: -
Q4. A stretched bow has more energy than a straight one.
Ans. The more the object is stretched, the greater is its potential energy. So a stretched bow has more energy than a straight one.

Q5. The energy of flowing water is very useful to us.
Ans. The flowing water has kinetic energy which is very useful in producing hydroelectric power which can be used to produce current.

Question and answers: -
Q4. Define : -
i) Potential energy: It is the energy stored in an object when it is in a raised or stretched position.
Eg. A raised hammer and stretched bow.

ii) Kinetic energy: It is the energy an object has when it is moving.
Eg. A moving ball and moving water.

Q5. What is a fuel?
Ans. Fuel is a substance that produces heat or power when it burns. A fossil fuel is a fuel made from the dead remains of plants and animals that lived thousand of years ago.
Eg. Coal, Petroleum

Q6. What are the various products that can be obtained from mineral oil?
Ans. Mineral oil is distilled in oil refineries to give petrol, paraffin wax, lubricating oil etc.


Give reasons: -
Q6. Mechanical energy is used in electrical appliances.
Ans. Electric energy is converted into mechanical energy in household machines like mixers, grinders and electrical fans.

Question and answers: -
Q7. What is law of conservation of energy?
Ans. Energy can not be created or destroyed. It can only be transformed from one form to another. This is law of conservation of energy.

Q8. Name some alternate sources of energy.
Ans. Some alternate sources of energy are sun, wind, wood, plant and animal wastes etc.

1. F / B
a. energy
b. heat
c. potential, kinetic
d. heat, light
e. biomass, biogas
f. wind



2. T / F
a. False
b. True
c. False
d. True
e. True
f. False



3. CT BA
a. Heat
b. created
c. steam
d. heat
e. Biogas

4. Match the following: -
a. two forms of mechanical energy.
b. is used in a music system.
c. is essential for cooking.
d. two alternate sources of energy
e. helps in the movement of aeroplanes.


4. THE UNIVERSE

New words: -
1. celestial 2. satellite 3. heavenly 4. essential

Questions and answers: -
Q1. Define i) star ii) planets iii) satellite
Ans. i) Star: - A star is a huge ball of hot glowing gases. It gives out heat and light.
ii) Planets: - Planets are large round celestial bodies that move around the sun.
iii) Satellite: - Satellites are heavenly bodies that orbit around the planet.

Q2. What is the solar system made up of?
Ans. The sun, the planets that go around it and their moons together make up the solar system.

Q3. Name the eight planets of the solar system.
Ans. Our solar system is made up of eight planets. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Q4. What are the moons? What are they also known as?
Ans. The heavenly bodies that revolve around the planet are known as moons. They are also called natural satellites.

New words: -
1. Artificial 2. Farthest 3. Concentric 4. Brightest

Give reasons: -
a. Artificial satellites are very useful to us.
Ans. Artificial satellites are useful for sending and collecting information. This information is used for studying space and forecasting weather and in radio / TV communication.

Question and answer: -
Q4. Name some artificial satellites launched by Indian scientists.
Ans. Some artificial satellites launched by Indian scientists are the Aryabhatta, Rohini, INSAT-IB and INSAT – 1C.

New words: -
1. Origin 2. Spherical 3. Helium 4. Hydrogen 5. Volcano
Give reasons: -
b. The solid rock inside the mantle melts at times to form lava.
Ans. The mantle is made up of hot rocks and melts the solid rocks inside. At times the molten material comes out from a hole on top of a hill or mountain. This is a volcano, and the hot molten material that oozes out from the mantle is lava.

New words: -
1. Spinning 2. Hemisphere 3. Position
Activity:- Make one child to stand as a Sun and the other child as Earth who is moving on its orbit and as well as around the Sun.
Give reasons: -
c. While one part of the Earth experiences day the other part experiences night.
Ans. The Earth spins from west to east on its axis. This is rotation and this causes day and night.

d. We have different seasons in a year.
Ans. The Earth revolves around the sun with its axis tilted to one side. This causes different seasons in a year.

e. When it is summer in India, its winter in Australia?
Ans. India has summer when Australia has winter because South Pole is tilted away from the sun, at that time. The Southern hemisphere receives less sunlight and experiences winter .

Question and answers: -
Q6. Define
i) Rotation: - The spinning of earth on it axis is called rotation. It takes 24 hours for earth to complete one rotation.

ii) Revolution: - The movement of Earth on its orbit around the sun is called revolution. The earth takes 365 ¼ days to complete the revolution.

Q7. What is astronomy? Name some famous Indian astronomers.
Ans. Astronomy is the study of heavenly bodies and their motions. Some famous Indian Astronomers were Aryabhatta and Bhaskara.

Q8. Who was the first Indian to reach space?
Ans. Rakesh Sharma was the first Indian to go to space.

Q9. What is Panchang? List the various things that we can know from it.
Ans. Panchang is the Indian calendar based on astronomy. It deals with the position and movement of eight planets. It helps us to know the position of different stars.

1. Fill in the blanks: -

a. sun c. Jupiter e. Aryabhatta, Rohini, INSAT – IB
b. Heat light d. natural f. mantle, core

2. True or False: -
a. False c. False e. False
b. False d. True f. True


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