STD-5, CHAPTER-12, OBSERVING THE SKY, EXTRA QUESTION ANSWERS

1.      The sun rises in the _____.

Ans: East

2.      The sun sets in the _____.

Ans: West

3.      State the cause of the apparent motion of the sun from east to west?

Ans: As the earth rotates from west to east, the sun appears to move from east to west.

4.      Name the morning star.

Ans: Mercury or venus

5.      Name the evening star.

Ans: Mercury or venus

6.      In which part of the sky are we likely to find Venus when it is visible as an evening star?

Ans: Venus is seen very low near the horizon in the sky.

7.      Name the brightest and most recognisable object in the night sky.

Ans: The moon is the brightest and most recognisable object in the night sky.

8.      Name the brightest object in the sky after the sun and the moon.

Ans: Venus is the brightest object in the sky after the sun and the moon.

9.      Name the planets which can be seen in the night sky even with the unaided eye.

Ans: Mars, venus, Jupiter and Saturn are the planets that can be seen in the night sky even with the unaided eye.

10.  Why cannot we see Uranus and Neptune with unaided eye?

Ans: We cannot see Uranus and Neptune with unaided eye, because they are very faint.

11.  Name the first planet discovered by using a telescope.

Ans: Saturn was the first planet discovered by using a telescope.

12.  How can we know about the temperature of stars from their colours?

Ans: The hottest stars shine with a whitish-blue light.

The other stars shine with a yellowish white light.

13.  The sun shines with a ______ light.

Ans: Yellowish-white light.

14.  Name the star nearest to the Earth.

Ans: The nearest star to the Earth is the Sun.

15.  Why do stars appear as points to us?

Ans: Stars appear as dim points in the night sky. This is due to their very large distances from us.

16.  Why the sun appears like a ball, while other stars appear points to us?

Ans: Almost all the stars are million of times farther away from us as compared to the distance of the sun from us. It is for this reason that the sun appears like a ball to us, but the other stars appear only as points or dots.

17.  Why do, we usually not see the stars during the day?

Ans: The stars are not visible during day-time due to sun’s brightness.

18.  Define the term ‘constellation’.

Ans: A constellation is a group of stars that appear to form some recognisable pattern or shape in the sky.

19.  Why was the concept of constellations important?

Ans: The concept of constellations was important as ancient people were dependent on these stars to find directions and to measure time.

20.  Name some constellations.

Ans: Some constellations are, Ursa Major (Big Dipper), Orion, Ursa Minor (Small Dipper) and Cassiopeia.

21.   Give a short description about Ursa Major.

Ans: i) Ursa Major is seen during the spring, in the early part of night.

ii) Ursa Major is also known as the Great Bear (or Big Dipper).

iii) There are seven prominent stars in Ursa Major.

iv) The two stars, at the top of this constellation, help to locate the Pole Star.

22.  How can we locate the Pole Star with the help of Ursa Major?

Ans: The two stars, at the top of Ursa Major, are called pointers. The line joining those points directs the position of the Pole star (North Star).

23.  In what respects is, the pole star, different from other stars?

Ans:i) The pole star, unlike other stars, appears to remain fixed at one place.

ii) This is so because it lies along the axis of rotation of the earth.

iii) Because of this special feature, this star has been useful to travellers. It defines the North direction.

24.  Write the difference between a planet and a star.

Ans:i) Planets appear like tiny discs whereas stars appear as points.

ii) Stars appear to twinkle. Planets do not twinkle.

iii) Stars appear to be almost stationary. Planets change their relative position with respect to each other.

25.  Planets appear as tiny discs whereas stars appear as points. Why?

Ans: A planet is closer to us than the stars. That is why, planets appear like tiny discs whereas stars appear as points.

26.  Why planets (wandering stars) are so named?

Ans: i) Planets change their relative position with respect to each other.

ii) They appear to move against the background of stationary stars.

iii) This was the reason why ancient people named them as planets i.e. wandering stars.

27.  A star appear to rise four minutes earlier every day. Give reason.

Ans: i) The earth revolves around the sun.

ii) Alongwith this revolution around the sun, the earth also rotates about its own axis.

iii) These two motions of the earth cause the same star to appear to rise four minutes earlier every day.

28.  We see a whole different set of stars in the sky after every six months. Give reason.

Ans: The earth revolves around the sun and, in six months time, moves to the other side of the sun. Therefore, we see a whole different set of stars in the sky after every six months.

STD-3, CHAPTER-9, COOKING AND EATING HABITS, EXTRA QUESTION ANSWERS

 1.      In what form, early man used to eat food?

Ans: Early man used to eat food in raw form.

2.      When did human learn to cook food?

Ans: After the discovery of ‘fire’, human learnt to cook food.

3.      What are the benefits of cooking food?

Ans: i) Cooking makes food soft, tasty and easily digestible.

ii) Cooked food can be preserved for a longer time.

iii) Cooking also makes the food germ free and safe to eat.

4.      Write two benefits of eating cooked food.

Ans: i) Cooked food is free from germs. So, it is safe to eat.

ii) Cooked food is also easy to digest.

5.      What can happen to vegetables when they are over cooked?

Ans: Vegetables contain many nutrients. When vegetables are over cooked, these nutrients are destroyed.

6.      Why should we wash the fruits and vegetables before eating?

Ans: We should wash the fruits and vegetables before eating to remove dust and impurities.

7.      List the different methods of cooking.

Ans: The different methods of cooking are,

i)       Boiling

ii)     Steaming

iii)   Baking

iv)   Frying

v)     Direct heating

8.      Name the methods of cooking which require water.

Ans: Boiling and steaming require water.

9.      Name some food items which are prepared by boiling.

Ans: Pulses, eggs, can be cooked by boiling. Milk is also boiled before consuming.

10.  Name the device/ utensil which is often used for boiling.

Ans: Pressure cooker is often used for boiling.

11.  How can you prepare dal?

Ans: i) First boil the seeds of particular plants.

ii) Add some spices to them, before eating.

12.  Which utensil is used for boiling eggs?

Ans: A metal bowl can be used for boiling eggs.

13.  Why should we boil milk before consuming?

Ans: i) Boiling kills germs that can spoil the milk.

ii) Boiling helps to preserve milk for a longer time.

So, we should boil milk before consuming.

14.  How steam is obtained?

Ans: Steam is obtained by boiling water.

15.  Name two food items which are prepared by the process of steaming.

Ans: Foods, like idli and dhokla, are prepared by the method of cooking.

16.  Write the benefits of steaming.

Ans: i) Steaming shortens the duration of cooking.

ii) Steaming helps to conserve the nutritive value of the food.

iii) Steam cooked food is also easy to digest.

17.  Name the vessel (utensil) used for steaming purpose.

Ans: A deep vessel or a steamer is used for steaming purpose.

18.  Define ‘baking’.

Ans: Indirect heating, with or without using oil, is known as baking.

19.  Name the food items prepared by baking.

Ans: Cakes, biscuits and breads are made by baking.

20.  How is baking done?

Ans: i) Baking is done by indirect heating, with or without using oil.

ii) It is mainly done in an oven.

21.  How are pakodas and jalebis prepared?

Ans: Pakodas and Jalebis are prepared by frying their ingredients in hot oil.

22.  Differentiate between boiling and frying.

Ans:

Boiling	Frying
It requires water.	It requires oil.
It is a healthy method of cooking food.	It is not a very healthy method of cooking food.

23.  Why it is advised to avoid fried food?

Ans: Fried food contains too much oil, which is not good for our health. So, it is advised to avoid fried food.

24.  Name the oldest method of cooking known to man.

Ans: ‘Direct heating’ is the oldest method of cooking food.

25.  Name the food item which is made by the direct heating method.

Ans: Chappatis are usually made by the direct heating method.

26.  Direct heating is done by keeping the food over _____.

Ans: Fire or Flame.

27.  Which utensil is used for making chappatis?

Ans: A griddle (tawa) is used for making chappatis.

28.  What are utensils?

Ans: Utensils are the containers that may be used for cooking or storing food.

29.  List some utensils used for cooking.

Ans: Some utensils are, pressure cooker, metal bowl, griddle (tawa), etc.

STD-3, CHAPTER-8: FOOD, EXTRA QUESTION ANSWERS

 1.      Why the living things need food?

Ans:i) Living things need food to live, grow and remain healthy.

ii) Food also gives us energy to do work.

2.      Name the two sources of our food.

Ans: The two sources of our food are, plants and animals.

3.      Who is a vegetarian?

Ans: The person who eats only plant products like vegetables, fruits and milk (animal product) is called a vegetarian.

4.      Who is a non-vegetarian?

Ans: The person who loves to eat fish, meat, chicken, eggs, is called as non-vegetarian.

5.      Which one is better- to be a vegetarian or nonvegetarian.

Ans: It is always better to be a vegetarian.

6.       Name the parts of plants which are used as food.

Ans: We eat seeds, fruits, roots, stems, leaves of the plants.

7.      Name the plants whose seeds are taken as food.

Ans: Seeds of Wheat plant, Rice plant, Corn plant, maize plant, are taken as food.

8.      How wheat flour is obtained?

Ans: Wheat flour is obtained by grinding the seeds (grains) of wheat.

9.      Name the food items prepared from wheat flour.

Ans: Chappatis and bread, are prepared from wheat flour.

10.  Name the food products obtained from the seeds of wheat.

Ans: We obtain wheat flour, Dalia, sooji (rawa) and maida, from the seeds of wheat.

11.  How are dosas and idlis prepared?

Ans: Dosas and idlis are prepared from a paste of ground rice and dal.

12.  Name some cereals.

Ans: Wheat, rice and corn are some of the cereals.

13.  How do cereals help us?

Ans: Cereals give us energy to do work.

14.  Name some pulses.

Ans: Different kinds of dal, peas, grams, are the pulses.

15.  Why should we eat pulses?

Ans: We should eat pulses, as they help us to grow.

16.  The seeds which are generally eaten raw, are the ______.

Ans: Nuts

17.  Name some nuts.

Ans: Peanuts, walnuts, cashewnuts and almonds are some nuts.

18.  Why do we need to eat nuts?

Ans: Nuts can provide a lot of energy to us and keep our body warm. So, we should eat nuts.

19.  What are green vegetables?

Ans: Leaves, which are cooked and taken as food, are called green vegetables.

20.  Name some leaves which are cooked before eating.

Ans: Spinach, fenugreek (methi), cabbage and mustard are cooked before eating.

21.  Name the leaves which are used for garnishing and flavouring our food.

Ans: Leaves of coriander, mint and curry plant are used for garnishing and flavouring our food.

22.  Why are leaves important for us?

Ans: Leaves protect us from diseases. So, they are important for us.

23.  Name the stems which are used as food.

Ans: Potato, onion, ginger and stem of lotus (kamal kakri) are taken as food.

24.  Potato is an ________ stem.

Ans: Potato is an underground stem.

25.  Name the roots which are eaten as food.

Ans: The roots which are taken as food are, carrot, radish, turnip and beetroot.

26.  Name some sweet and juicy fruits. (OR)  Name some fruits which are eaten raw.

Ans: Mangoes, oranges, grapes, muskmelons and watermelons are some juicy fruits which are eaten raw.

27.  Name some fruits which are eaten as vegetables (after cooking).

Ans: Brinjal, ladyfinger are eaten after cooking as vegetables.

28.  Name the fruit which can be eaten raw as well as cooked.

Ans: Tomatoes

29.   Why are green vegetables and fruits important for us?

Ans:i) Green vegetables protect us from diseases.

ii) Fruits keep us fit and healthy. They also protect us from diseases.

So, green vegetables and fruits are important for us.

30.  List some animal products that we eat.

Ans: Animal products like milk, eggs, meat and fish, are some of the animal products that we eat.

31.  Name the animals who give us milk.

Ans: Cow, buffalo and goat provide us milk.

32.  Name some food products where milk is used.

Ans: Curd, cheese, ice cream, kheer, etc., are the food products where milk is used.

33.  _____ is considered to be a complete food.

Ans: Milk

34.  Why is milk considered to be complete food?

(OR) Why are milk and milk products, regarded as ‘good food’ for one and all?

(OR) Why is milk important for growing children?

Ans: i) Milk is a very good source of nutrients for one and all.

ii) It helps us to grow, gives us energy and protects us from diseases.

So, it is regarded as ‘good food’ for one and all and is very important for growing children.

35.  Name the birds who give us eggs.

Ans: Poultry birds like hen, goose and duck give us eggs.

36.   List the factors on which the intake of food of different persons depend.

Ans: The factors on which intake of food depends are,

i)       Age of the person

ii)     Occupation of the person

iii)   Type of physical activity

iv)   Gender of the person

37.  Ramesh is a labour, working at the construction sites. Suresh, is a bank officer. Who do you think needs more food to eat? And why?

Ans:i) Ramesh needs more food to eat.

ii) As Ramesh is doing more physical activity than Suresh, so he needs more energy.

38.  How the food habits of a person depends on his/her age?

Ans: i) From birth, till about four months of age, small babies take milk only.

ii) When a child is nearly six months of age, he/she is given soft pieces of fruit and semi-solid foods. The child continues to take milk also.

iii)Growing children and young persons, need to eat proper amounts of a balanced diet.

iv)In old ages, people prefer easily digestible simple food.

39.  Name the food items which are included in a balanced diet?

Ans: The balanced diet include rice, vegetables, chappatis, dal, dosa, idli, uttapam, sambhar, fruits, nuts, milk and milk products.

40.  What is over eating? How it affects our body?

Ans:i) Eating too much is called over eating.

ii) Over eating makes us fat or obese.

iii)We will not be very active and healthy.