STD-3, CHAPTER - 5: ANIMALS, EXTRA QUESTION ANSWERS

1.      What do you mean domestic animals?

Ans: Those animals who live in and around our home, are called domestic animals.

2.      Give five examples of domestic animals.

Ans: Five examples of domestic animals are, dog, cat, cow, goat and pig.

3.      What do you mean by wild animals?

Ans: Those animals who do not live in or around our home and usually live in forests, are called wild animals.

4.      Give some examples of wild animals.

Ans: Some examples of wild animals are, lion, tiger, Rhino, deer, kangaroo etc.

5.      Name the animal who guards our house.

Ans: Dog guards our house.

6.      Name the animals who give us milk.

Ans: Cow and goat give us milk.

7.      Name the animal which has a horn on its head.

Ans: Rhino has a horn on its head.

8.      Name the bird which has a light green colour body and a red beak.

Ans: Parrot has a green colour body and a red beak.

9.      Define “habitat”.

Ans: A place where an animal lives is called its habitat.

10.  How the animals are classified on the basis of their habitat?

Ans: Animals are classified as, Land animals, Water animals and Aerial animals, on the basis of their habitat.

11.  Define “Terrestrial animals”.

Ans: Animals living on land are also called terrestrial animals.

12.  Name some terrestrial animals who live in plains.

Ans: Horse, cow, buffalo, dog, cat, donkey are some of the animals who live in plains.

13.  Name some animals living in deserts.

Ans: Camel, snake, lizard are some of the animals living in deserts.

14.  State the special features which help a camel to live in a desert.

Ans: i) Camels can tolerate high temperatures.

ii) Camels can store water and food in their bodies.

iii) Camels have padded feet that help them to walk on sand.

15.  Which type of feet do camels have?

Ans: Camels have padded feet.

16.  Which feature helps camels to walk on sand?

Ans: Camels have padded feet that help them to walk on sand.

17.  Which feature helps camels to live without water for many days?

Ans: Camels can store water and food in their bodies. This helps them to live without water for many days.

18.  How do lizards and snakes move on the ground?

Ans: Lizards and snakes crawl on the ground.

19.  How do lizards and snakes escape the heat of the desert?

Ans: Lizards and snakes live in burrows. This helps them to escape the heat of the desert.

20.  What are burrows?

Ans: Burrows are the small hollow areas under the earth.

21.  Name any two things that forests provide to animals.

Ans: Forests provide food and shelter to animals.

22.  Name some animals who live in forests.

Ans: Animals like tiger, zebra, elephant, giraffe, deer, kangaroo, live in the forests.

23.  How do skin colours and body patterns of some animals help to save them from danger?

Ans: The colour of the skin and body patterns of some animals, help them to merge with their surroundings and thereby, protecting them from danger.

24.  Where the cold regions of earth located?

Ans: The cold regions are located near the north and south poles of the earth.  

25.  Name some animals living in the snow covered areas.

Ans: Some animals who live in the snow covered areas are, polar bear, snow leopard, penguin, arctic hare.

26.  How the polar bear and snow leopard protect themselves from cold?

Ans: Polar bear and snow leopard have thick fur to protect their bodies from cold.

27.  Name some water bodies.

Ans: Ponds, lakes, rivers and oceans are some water bodies.

28.  Name some fresh water bodies.

Ans: Some fresh water bodies are, lakes, ponds and rivers.

29.  Name some salty water bodies.

Ans: Seas, oceans and some lakes are the examples of salty water bodies.

30.  Define aquatic animals.

Ans: Animals living in water are called aquatic animals.

31.  Give some examples of aquatic animals.

Ans: Fish, dolphins, whales, octopus, seal, jellyfish, shark, are some examples of aquatic animals.

32.  Name some animals who live in fresh water bodies.

Ans: Fish, like catla, labeo, trout, piranha, live in fresh water bodies.

33.  Name some animals who live in salty water bodies.

Ans: Animals, like whale, shark, turtle, starfish and jellyfish, live in salty water bodies.

34.  Name some land animals who stays in water for most of the time.

Ans: Frogs, toads, crocodile, turtle are some of the land animals who stays in water for most of the time.

35.  Why do frogs need water?

Ans: Frogs need water for laying eggs.

36.  Which feature helps frog to stay in water?

Ans: i) Frogs have webbed feet for swimming.

ii) Frogs can also breathe in water.

37.  Which feature helps turtles to swim in water?

Ans: Turtles have flippers for swimming.

38.  What are flippers?

Ans: Flippers are the paddle like organs for swimming.

39.  When do the turtles come to land?

Ans: Turtles come to land when they have to lay eggs.

40.  The crocodile lives near water and can also swim. Is it a water animal or land animal?

Ans: Crocodile is a land animal.

41.  How the crocodile moves in water?

Ans: The crocodile crawls on the ground.

42.  Where do dolphins live?

Ans: Dolphins live in oceans.

43.  Why are dolphins considered to be intelligent animals?

Ans: Dolphins can easily learn to perform tricks and play games. So, dolphins are considered to be intelligent animals.

44.  Name some friendly animals.

Ans: Dogs, cats are friendly animals.

45.  Why dogs, cats are called friendly animals?

Ans: Dogs, cats like to interact and play with humans. They also love their masters.  So, they are friendly animals.

46.  Name some shy animals.

Ans:  Deer, orangutans, tigers and snakes, are shy animals.

47.  Why deer/tiger/ orangutans/ snakes, are called shy animals?

Ans: Because they do not like to interact with humans. Humans, also try to avoid most of such animals. So, they are called shy animals.

STD-4, CHAPTER-6 : INSECTS, EXTRA QUESTIONS AND ANSWERS

1.      What are insects?

Ans: Tiny creatures around us are called insects.

2.      Give some examples of insects.

Ans: Houseflies, mosquitoes, butterflies, grasshoppers, beetles and bees, are some examples of insects.

3.      _______ are the largest group of animals on the earth.

Ans: Insects

4.      Give some characteristics of insects.

Ans:i) Insects do not have bones.

ii) All insects have three pairs of legs, that is, six legs in all.

iii) Many of them two pairs of membranous wings that help them to fly.

5.      Name some insects which get attracted towards fresh flowers.

Ans: Butterflies, honeybees and bumblebees, get attracted towards fresh flowers.

6.      Define pollination.

Ans: The process, of shifting of pollen grains from one place to another, is called pollination.

7.      How do insects help in pollination?

Ans: When insects sit on flowers, pollen grains stick to their legs or wings and get transferred to another place. Thus, insects help in pollination.

8.      Why are bees, ants called social insects?

Ans: Insects like bee, ants and termites live in well-organized colonies. They are called social insects.

9.      Name some useful insects.

Ans: Honeybee, silk moth, lac insect and lady bird beetle are some useful insects.

10.  Where do honeybees build their hives?

Ans: Honeybees build their hives on trees and roofs of old buildings.

11.  What is nectar?

Ans: The sweet smelling liquid of the flowers is called nectar.

12.  A beehive consists of many six-sided chambers called ______.

Ans: Combs

13.  How do honeybees make honey?

Ans: i) Honeybees suck nectar from flowers and carry it to the hive.

ii) Honeybees store the nectar in the combs of beehive.

iii) The nectar changes into honey in the combs.

14.  Where do bees store the nectar?

Ans: Bees store the nectar in the combs of beehives.

15.  How is honey collected from the beehives?

Ans:i) Honey is collected from a beehive by lighting a fire under it.

ii) The heat and smoke drives the bees out of the hive.

iii) The honey collectors then remove the hive and collect the honey stored in it.

16.   What are drones?

Ans: The male bees are called as drones.

17.  There is only one _____ in a beehive.

Ans: Queen bee

18.  Name the insect that gives us silk. What does it feed on?

Ans: Silk moth gives us silk. It feeds on mulberry leaves.

19.  How are cocoons formed?

Ans: The silk moth secretes a liquid which changes into a fine thread.

ii) The moth weaves a cover around itself with this thread. This cover is called a cocoon. Thus, a cocoon is formed.

20.  What is the difference between apiculture and sericulture?

Ans:i) Rearing or breeding of honeybees for collection of honey is called apiculture.

ii) Rearing of silkworms for getting silk is called sericulture.

21.  Lac insects usually grow on ______ trees.

Ans: Banyan trees

22.  What is lac? State its four uses.

Ans: i) The semi-solid substance secreted by lac insect is called Lac.

ii) Lac is used in paints, varnishes, printing ink, and for making bangles.

23.  How do lady bird beetles help plants?

Ans: Lady bird beetles eat a large number of pests that are harmful for plants. Thus, it protects the plants from pests.

24.  Name some harmful insects.

Ans: Houseflies, mosquitoes, head lice, bed bug, dog flea, cat flea, rats, are the harmful insects.

25.  Name the diseases that get spread by houseflies.

Ans: Houseflies spread diarrhea, cholera, jaundice, etc.

26.  Which organ gets infected in cholera disease?

Ans: Intestine gets infected in cholera disease.

27.  Which organ is infected in Jaundice?

Ans: Liver is infected in jaundice.

28.  Why should we not eat uncovered food?

Ans: We should not eat uncovered food as it is likely to have germs in it.

29.  How do houseflies spread diseases?

Ans: i) When houseflies sit on garbage or animal excreta, they gather germs on their feet and bodies.

ii) When these flies sit on any food item, the germs are passed on to the food.

iii) These disease causing germs get transmitted to the humans when they consume such infected food or water.

30.  Name the diseases that are spread by mosquitoes.

Ans: Mosquitoes spread malaria and dengue.

31.  Name the mosquito that spreads malaria.

Ans: Female Anopheles mosquito

32.  Name the mosquito that spreads dengue.

Ans: Aedes mosquito 

33.  How do mosquitoes spread diseases?

Ans:i) When a mosquito bites a sick person, it sucks the infected blood.

ii) When this mosquito bites a healthy person, it transfers the germs of the disease into the blood of that person.

Thus, the mosquitoes spread diseases.

34.  What are fleas?

Ans: Some blood sucking insects are wingless. Such insects are known as fleas.

35.  What causes Bubonic plague?

Ans: Fleas, found on rodents like rats, can spread Bubonic plague.

36.  Name some stinging insects.

Ans: Bee and wasp are stinging insects.

37.  How many legs does a spider have?

Ans: A spider has eight legs.

38.  How a spider is different from an insect?

Ans: A spider has eight legs whereas insects have six legs only.

39.  How does a spider make its web?

Ans: A spider secretes a liquid from its mouth, which changes into a very thin thread, when it comes in contact with air.

40.  How can we save ourselves from harmful insects?

Ans: i) We should maintain cleanliness and hygiene.

ii) We can get rid of harmful insects by using natural methods, or by using chemicals, called insecticides or pesticides.

iii) We often keep dried neem leaves in clothes or apply neem or kerosene oil on wooden furniture. This helps to save them from harmful insects.

iv) Farmers, sometimes, use pesticides, for saving their crops.

STD-5, CHAPTER-6, EXTRA QUESTION QUESTIONS

1.      Give any three reasons for spoilage of food.

Ans: Three reasons for spoilage of food are, micro-organisms, enzymes, insects, worms and rats.

2.      What are micro-organisms?

Ans: Micro-organisms are the organisms which are too small to be seen by unaided eye.

3.      Name two micro-organisms.

Ans: Bacteria and fungi

4.      State two factors that contribute to the fast growth of micro-organisms.

Ans: Two factors that contribute to the fast growth of micro-organisms are, moisture and temperature.

5.      How can we check the growth of micro-organisms in our food?

Ans: For checking the growth of micro-organisms in our food, we need to:

i)   Remove moisture from food i.e. dry it.

ii) Keep the food at low temperature (in the refrigerator)

6.      What are enzymes?

Ans: Enzymes are chemicals that are present in all fruits and vegetables which speed up chemical changes in them.

7.      How do enzymes help fruits?

Ans: i) Enzymes are useful because they cause ripening of fruits.

ii) When green fruits ripen, they change their colour and become sweet.

8.      How enzymes contribute to the spoiling of food products?

Ans: i) Enzymes speed up chemical changes that result in the loss of flavour, colour and appearance.

ii) They, thus, contribute to the spoiling of the food products.

9.      How can we protect our food items from insects, worms and rats?

Ans: i) We should keep the cupboards, shelves and containers clean and dry.

ii) This will prevent them from making a home at places where our food items are kept.

10.  Suggest any three ways to prevent spoilage of food.

Ans: i) Perishable food stuffs, like milk, meat, fruits and vegetables, must be stored in the refrigerator.

ii) Foods, like spices, cereals, biscuits and other snacks, should be kept in airtight jars.

iii) By preserving food.

11.  What do you understand by food preservation?

Ans: Food preservation is the process of treating and handling of food to stop, or slow down, the spoilage caused by micro-organisms.

12.  Describe the methods that are used for preservation of food.

Ans: i) Dehydration: In this process, water content of the food stuff is removed.

ii) Food can be preserved by adding salt and sugar.

iii) Food can be preserved by adding acetic acid, in the form of vinegar.

iv) Canning and Bottling: Food is cooked and sealed in sterile cans or jars and these containers are boiled to kill any remaining bacteria.

v) Pasteurisation: In this process, food product is subjected to pressurised heating, for a short time, followed by immediate cooling.

vi) Refrigeration: This procedure uses low temperature to prevent growth of micro-organisms.

vii) Vacuum packing:  In this method air is removed from the package prior to sealing.

13.  How the process of dehydration help to preserve food?

Ans: i) In dehydration process, water content is removed from the food stuff.

ii) Since, micro-organisms need water to grow, they cannot multiply, or grow, on dried foods.

14.  Name some food items which are preserved by the process of dehydration.

Ans: Many vegetables like onions, cauliflower, are preserved by the process of dehydration.

15.  How adding sugar and salts help in preserving food?

Ans: Sugar and salt tend to take out moisture from the food so that it is not available for growth of micro-organisms.

16.  Name some food items which are preserved by adding sugar and salt.

Ans: Pickles and jams can be preserved by adding salt and sugar in them.

17.  Name the food items where vinegar is used as a food preservative.

Ans: Vinegar is used as a food preservative in pickles.

18.  Name the food items which are canned to preserve them.

Ans: Many fruits, vegetables and meat products are canned to preserve them.

19.  What is pasteurisation? What is the maximum temperature used in this process?

Ans: i) Pasteurisation is the process of heating food followed by immediate cooling, to limit the growth of micro-organisms.

ii) The temperature used during pasteurisation is below 212⁰ F (100⁰ C).

20.  Why we should not drink unpasteurised milk?

Ans: Drinking unpasteurised milk is not safe as we can get diseases due to the presence of disease causing micro-organisms.

21.  Who discovered the process of pasteurisation?

Ans: Louis Pasteur discovered the process of pasteurisation.

22.  Why is it advised to keep the pasteurised milk under refrigeration?

Ans: i) Milk is pasteurised to kill micro-organisms.

ii) However, many more heat-resistant organisms only get reduced in number and do not get completely removed.

iii) Hence the pasteurised milk must generally be stored under refrigeration to keep bacterial growth in it under control.

23.  How pasteurisation increases the shelf life of milk?

Ans: Pasteurisation destroys the micro-organisms. It also deactivates some enzymes and increases the shelf life of milk.

24.  Why does food stay fresh for a longer time when stored in a refrigerator?

Ans: i) The temperature is low inside a refrigerator.

ii) Micro-organisms and enzymes get deactivated at low temperatures and hence, the spoilage of food gets prevented.

25.  How the process of vacuum packing preserves food?

Ans: i) In this method, air is removed from the package prior to sealing.

ii) The vacuum, thus created, reduces oxygen in the package. This limits the growth of bacteria or fungi in the package.

26.  Which food items are preserved by vacuum packing?

Ans: Dry foods like cereals, nuts, coffee, cheese and potato chips are preserved by the process of vacuum packing.

27.  Foods, containing fats and oils, become rancid in the presence of _______.

Ans: Oxygen

28.  Packets of potato chips and other namkeens are filled with ______ gas.

Ans: Nitrogen

29.  How is food preservation useful to us?

Ans: Food preservation is helpful in many ways:

i)                    It helps to maintain nutritive value of food.

ii)                  It increases the shelf life of food, thus, increasing its supply. Many perishable foods can be preserved for a long time.

iii)                It makes seasonal foods available throughout the year.

iv)                It decreases wastage of food by preventing decay or spoilage of food.

It helps in adding variety to the diet.