STD-5, CHAPTER-6: SPOILAGE AND WASTAGE OF FOOD AND FOOD PRESERVATION, EXERCISE QUESTION AND ANSWERS

 

A.     FILL IN THE BLANKS.

1.      Micro-organisms like bacteria and ________ spoil the food.

Ans: Fungi

2.      Insects make their home in _______ and _______ places.

Ans: moist and dark places

3.       Enzymes can be harmful because they can cause ______ of fruits and vegetables.

Ans: spoilage

4.       Snacks, like biscuits and chips, should be stored in _______ jars.

Ans: airtight

5.      The growth of micro-organisms slows down at _______ temperatures.

Ans: lower

B.      WRITE TRUE OR FALSE FOR THE FOLLOWING STATEMENTS.

 

1.      Growth of bread moulds, on bread, indicates that it has got spoiled.                    True

2.      Vinegar is used as a preservative.                                                                                   True

3.      It is safe to drink unpastuerised milk.                                                                            False

4.      We can eat more than the required quantity.                                                              False

5.      We may eat spoiled food rather than wasting it.                                                         False

 

C.      TICK THE CORRECT OPTION.

 

1.      A natural insect repellent, found in our kitchens, is -

(a)   salt                (b) sugar         (c) turmeric powder           (d) wheat flour

      Ans: turmeric powder

2.      Dry foods, like cereals and nuts, are preserved by -

(a)   Adding salt and sugar         (b) vacuum packing          (c) dehydration         (d) pasteurisation

      Ans: vacuum packing

3.      Fruits and vegetables get ripened due to the action of-

(a)   enzymes       (b) bacteria        (c) fungi       (d) insects

       Ans: enzymes

4.      The least perishable food item, from the following, is-

(a)   milk                      (b) biscuits

(c)    meat                    (d) curd

      Ans: curd

5.      The chances of spoilage of food can be reduced by keeping the food -  

(a)   moist       (b) warm        (c) at low temperatures       (d) in open containers

       Ans: at low temperatures

D.     ANSWER THE FOLLOWING QUESTIONS IN BRIEF.

 

1.      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.

2.      What is likely to happen to curd if it is not stored in the refrigerator?

Ans: If curd is not stored in the refrigerator, then it is likely to change its smell and will become sour. In other words, it will get spoiled.

3.      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.

4.      How can we protect our food 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.

5.      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.

E.      ANSWER THE FOLLOWING 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.      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.

3.      Why is it important to check the manufacturing and the expiry date of packaged food items before consuming them?

Ans: Some food items are preserved by the process of canning, bottling or by vacuum packing. But, these food items start to spoil after a certain period of time. So, it is important to check the manufacturing and the expiry date of packaged food items before consuming them.

4.      Explain the following methods of food preservation:

(a)   Dehydration  (b) Canning and Bottling    (c) Pasteurisation

Ans: a) Dehydration: The process of food preservation in which water content of the food stuff is removed, is called dehydration.

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

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

5.      Rakesh bought two raw papayas. He kept one papaya in the refrigerator and other papaya on the kitchen shell. Which will ripen and Why?

Ans: The papaya kept in the kitchen shell will ripen faster, due to the action of enzymes. Whereas, the action of enzymes slows down for the papaya, which is kept at a low temperature inside the refrigerator.

STD-4, CHAPTER-6: INSECTS, EXERCISE QUESTION AND ANSWERS

 A.     FILL IN THE BLANKS.

1.      Butterflies are attracted to ______ flowers

Ans: coloured or scented (both are correct)

2.      Honeybees suck ______ from flowers.

Ans: nectar

3.      The six-sided chambers of beehives are called ________.

Ans: Combs

4.      Malaria is spread by the bite of female _________.

Ans: Anopheles

5.      The cover, weaved by a silk moth, around itself is called a _______.

Ans: Cocoon

6.      Bees and ______ are stinging insects.

Ans: wasp

B.      WRITE TRUE OR FALSE FOR THE FOLLOWING STATEMENTS:

1.      Insects help in pollination.                                                               True

2.      Lac insects grow on banyan trees.                                                 True

3.      Houseflies spread malaria.                                                              False

4.      Aedes mosquito spreads dengue.                                                  True

5.      Bubonic plague is caused by a mosquito.                                     False

 

C.      TICK THE CORRECT OPTION.

 

1.      The insect, that usually spreads jaundice, is the-

(a)   Mosquito        (b) wasp          (c)  housefly       (d) butterfly

      Ans: housefly

2.      Honeybees make honey from –

(a)   lac       (b) nectar           (c) milk           (d) sugar

      Ans: nectar

3.      The sting of insects, like the bees and wasps, is located on their –

(a)   wing       (b)  back       (c) mouth       (d) leg

       Ans: back

4.      An insect, that helps to save our crops from pests, is the–

(b)   wasp       (b)  lady bird beetle       (c) bee       (d) butterfly

       Ans: lady bird beetle

STD-4, CHAPTER-7: FOOD, EXTRA QUESTION AND ANSWERS

1.      Name some food items obtained from plants.

Ans: We obtain fruits, vegetables, spinach, nuts, pulses etc. from plants.

2.      Name some food items obtained from animals.

Ans: We obtain milk, meat, eggs, chicken, from animals.

3.      What are nutrients? How do nutrients help us?

Ans:i) Nutrients are substances, present in the food.

ii) They provide us energy, help us to grow, keep us healthy, disease free and strong.

4.      Name some nutrients present in our food.

Ans: Carbohydrates, proteins, fats, vitamins and minerals are the main nutrients in our food.

5.      Name the nutrients which are called as energy giving foods.

Ans: Carbohydrates and fats are called as energy giving foods.

6.      Why carbohydrates and fats called energy giving foods?

Ans: Carbohydrates and fats provide energy to our body, thereby, help it perform various functions.

7.      What is the function of fats in our body?

Ans: i) Fats provide energy to our body.

ii) Fats also keep us warm.

8.      Name some sources of carbohydrates.

Ans: Rice, wheat, maize, sugar, potatoes, honey and sugarcane, are some sources of carbohydrates.

9.      Name some sources of fat.

Ans: Butter, oil, ghee, nuts and meat, are the sources of fat.

10.  Which gives more energy carbohydrates or fats?

Ans: Fats give more energy than carbohydrates.

11.  One gram of carbohydrate gives about ______ kilocalories of energy.

Ans: Four kilocalories

12.  One gram of fat gives about ______ kilocalories of energy.

Ans: Nine kilocalories

13.  What are body-building foods?

Ans: Foodstuffs, containing proteins, are called body building foods.

14.  Name some food items which contain proteins.

Ans: Milk, eggs, pulses, cheese, fish and nuts, contain proteins.

15.   Name two food items, obtained from animals, that are good sources of proteins.

Ans: Milk and eggs are good sources of proteins.

16.  Name two food items, obtained from plants, that are good sources of proteins.

Ans: Pulses and nuts, are good sources of proteins.

17.  State the main role of proteins for our body.

Ans: Proteins help our body to grow and repair the worn-out tissues.

18.  Name the nutrients which are called protective foods.

Ans: Vitamins and minerals are called protective foods.

19.  Why are vitamins and minerals called protective foods?

Ans: Vitamins and minerals, protect our body from diseases and keep us healthy. So, foodstuffs containing vitamins and minerals are called protective foods.

20.  Name the different types of vitamins.

Ans: The different types of vitamins are, vitamin A, Vitamin B, Vitamin C, Vitamin D, Vitamin E and Vitamin K.

21.  Our body needs _______ in small quantities.

Ans: Vitamins and minerals.

22.  Name the sources of Vitamin A.

Ans: Spinach, yellow fruits like mango and papaya; carrot, butter, eggs are the sources of Vitamin A.

23.  What is the function of Vitamin A in oour body?

Ans: Vitamin A is necessary for good eye-sight and healthy skin.

24.  Name the sources of Vitamin B.

Ans: Green leafy vegetables, soyabean, milk, beans, peas are the sources of Vitamin B.

25.  What is the importance of Vitamin B in our body?

Ans: Vitamin B is required for healthy skin and proper functioning of nerves.

26.  Name the sources of Vitamin C.

Ans: Orange, lemon, amla, tomato, green vegetables are the sources of vitamin C.

27.  Why Vitamin C is required by our body?

Ans: Vitamin C is needed for proper functioning of blood vessels, for keeping gums helathy, and for healing of wounds.

28.  Name the Vitamin that our body makes in the presence of sunlight.

Ans: Our body makes vitamin D in the presence of sunlight.

29.  Name the sources of Vitamin D.

Ans: Sunlight, milk, eggs, butter, fish, cod liver oil are the sources of vitamin D.

30.  What is the importance of Vitamin D in our body?

Ans: Vitamin D helps our body to use calcium for strengthening our bones and teeth.

31.   Name some minerals that are needed by our body.

Ans: Calcium, phosphorus, iron and iodine are some minerals that are needed by our body.

32.   Name the sources of calcium.

Ans: Milk, green leafy vegetables are the sources of calcium.

33.  What is the function of Calcium in our body?

Ans: Calcium is required for healthy bones and teeth.

34.  Name the sources of Phosphorus.

Ans: Milk, egg, fish, green vegetables, pulses are the sources of phosphorus.

35.  What is the importance of phosphorus in our body?

Ans: Phosphorus is needed for healthy bones and teeth.

36.  Name two minerals that are required for healthy bones and teeth. Also mention one food source that contains both of them.

Ans:i) Calcium and Phosphorus are required for healthy bones and teeth.

ii) Milk contains both calcium and phosphorus.

37.  Name the sources of iron.

Ans: Pulses, nuts, spinach, beans, apples, are the sources of iron.

38.  How iron helps our body?

Ans: Iron is required for the formation of haemoglobin in our blood and to protect us from infections.

39.  Name the sources of Iodine.

Ans: Iodised table salt, sea foods like fish and prawns are the sources of iodine.

40.  Why iodine is necessary?

Ans: Iodine is necessary for normal growth and development of the body.

41.  What is roughage?

Ans: Roughage is a fibre present in the food.

42.  Why is it advisable to eat food items like whole fruits, salads and whole grains?

Ans: i) Whole fruits, salads and whole grains contain fibres or roughage.

ii) These fibres helps our body to get rid of undigested food.

iii) Fibres also help us to avoid over-eating.

So, it is advisable to eat food items like whole fruits, salads and whole grains to get fibres.

43.  Why do we say that water is essential for proper functioning of our body?

Ans:i) Water helps in digestion of food and absorption of nutrients in our body.

ii) It also helps in throwing out wastes from the body.

Thus, water is essential for our body to function properly.

44.  We should drink at least ________ glasses of water everyday.

Ans: Eight to ten

45.  Sugar contains carbohydrates, but lacks ______, _____ and ______.

Ans: Fats, proteins and minerals.

46.  Define a balanced diet.

Ans: A diet which contains all the nutrients, roughage and water, in right amounts, is called a balanced diet.

47.   Why should we eat a balanced diet?

Ans: i) All nutrients are not available in any one food item.

ii) Absence of any one nutrient from our diet, over the years, can affect our growth and proper functioning of the body.

iii) A balanced diet contains all the nutrients, roughage and water in appropriate amounts.

So, we should eat a balanced diet.

48.  ‘Old people need less of proteins, carbohydrates and fats than young children.’ Justify this statement.

Ans:i) Young children are very active, as they do a lot of work. They require more energy and strength. So, they need more proteins, carbohydrates and fats.

ii) But, old people are not very active. They need less energy. So, they need less carbohydrates, fats and proteins.