Chapter 2 Components of Food

  1. The main source of food are plants and animals.
  2. Different kind of food contains different components needed by our body and these components are known as nutrients.
  3. The major nutrients are carbohydrates, protein, fat, minerals, dietary fibers and water that is present in our body.
  4. A diet which contains all the essential nutrients in an appropriate amount is known as balanced diet.
  5. Excess intake of fat causes obesity.
  6. The nutrients when taken in excess then they can destroy our body posture.
  7. Deficiency of these nutrients may cause our body weak and feeble. It may cause a number of diseases.
  8. Vitamins helps us to protect our body from the diseases. Vitamins are of many types like vitamin A, vitamin C, vitamin D, vitamin E etc.
  9. Deficiency of vitamins may cause loss of vision, Beri- Beri, scurvy, rickets and other diseases that may affect the reproductive health.
  10. Calcium, phosphorus, iodine are the minerals which makes our teeth, bones and muscles strong.

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Exercise 1 ( Page No. : 17 )

  • Q1 Name the major nutrients in our food.
    Ans:

    Carbohydrate, vitamins, minerals, proteins, fats, dietary fibers and water are the major nutrients that are present in our food. Carbohydrates and fats are also called the energy bank of our body. Vitamins helps us to protect the body against diseases. The growth and maintenance of the body is done by the proteins.


    Q2 Name the following: (a) The nutrients which mainly give energy to our body. (b) The nutrients that are needed for the growth and maintenance of our body. (c) A vitamin required for maintaining good eyesight. (d) A mineral that is required for keeping our bones healthy.
    Ans:

    (a) Carbohydrates and fats

    These are the two main nutrients which provides the energy to our body. These nutrients mainly found in potato, ghee, milk, sugarcane etc.

    (b) Protein

    Protein is the main nutrient which helps in growth and maintenance of tissues and cells of our body. For example: milk, cheese, fish etc.

    (c) Vitamin A

    Vitamins protect our body against diseases and is also responsible for good eye sight. Due to the deficiency of this vitamin, people may suffer from loss of his vision. It is commonly found in green leafy vegetables, milk, fish etc. which keeps our skin and eye sight healthy.

    (d) Calcium

    Calcium keeps teeth and bones strong. Due to the deficiency of calcium bones become too weak and tooth decay can also occurs. To keep teeth and bones strong we should eat milk, egg, soyabean etc.


    Q3 Name two foods each rich in: (a) Fats (b) Starch (c) Dietary fibre (d) Protein
    Ans:

    Name two foods rich in:

    1. Fats: Groundnut, cheese, milk, butter and oily food contains fat. Fats are also the source of energy and which makes our skin soft and shiny.
    2. Starch: Rice, wheat, potato, maize etc. Rice is the main source of starch. As like fats, starch is also the source of energy. Its deficiency makes the body weak and feeble.
    3. Dietary fibres: Potato, pulses, wheat grains, fresh fruits etc. dietary fibres do not give any nutrition to our body but they help to remove the undigested food from the body.
    4. Protein: Milk, cheese, egg, fish, curd etc. are the protein rich food which give our body a balanced amount of protein for the growth and maintenance of our body.  

    Q4 Tick (√) the statements that are correct. (a) By eating rice alone, we can fulfill nutritional requirement of our body. ( ) (b) Deficiency diseases can be prevented by eating a balanced diet. ( ) (c) Balanced diet for the body should contain a variety of food items. ( ) (d) Meat alone is sufficient to provide all nutrients to the body. ( )
    Ans:

    (a) False                                                                                                                                                                                                                                  Because rice is rich in carbohydrate, but our body needs protein, fats, minerals, dietary fibres and water also. So rice alone cannot fulfill the nutritional requirement of our body.

    (b) True                                                                                                                                                                                                                                            In the balanced diet all nutrients are present in an appropriate amount. According to the body needs, deficiency disease can be prevented by eating a balanced diet.

    (c) True                                                                                                                                                                                                                                            Because different kind of nutrients present in different kind of food. So, a balanced diet for the body should contain a variety of food items.

    (d) True                                                                                                                                                                                                                                        Yes, it is so because our body needs carbohydrates, proteins, fats, vitamins, minerals and water also. But in meat all these nutrients are not present. So to fulfill the deficiency of other nutrients, we have to add different kind of food items in our diet.


    Q5 Fill in the blanks. (a) ______________ is caused by deficiency of Vitamin D. (b) Deficiency of ______________ causes a disease known as beri-beri. (c) Deficiency of Vitamin C causes a disease known as ______________. (d) Night blindness is caused due to deficiency of ____________ in our food.
    Ans:

    (a) Rickets                                                                                                                                                                                                                                    The source of vitamin D is sunlight. If the deficiency of vitamin D occurs, then our bones become tilted.

    (b) Deficiency, Vitamin B1                                                                                                                                                                                                    Papaya, carrot, mango are the sources of vitamin B1. Due of deficiency of this vitamin, muscles becomes weak.

    (c) Scurvy                                                                                                                                                                                                                                  Vitamin C generally found in sour food materials like orange, lemon, tomato etc. Due to deficiency of vitamin C, bleeding gums problems can occur.

    (d) Vitamin A                                                                                                                                                                                                                          Vitamin A is commonly found in green leafy vegetables, milk, fish etc. which keeps our skin and eye sight healthy. Due to its deficiency our eye sight becomes poor and sometimes complete loss of vision occur.