Biology

NIOS Class 12 Biology Nutrition and Health Terminal Exercises

NIOS Biology Chapter 28 Solutions offer detailed answers to terminal exercises. The chapter includes important concepts necessary for exam success in Class 12 Biology. These solutions are simple, structured, and help learners revise quickly.

By practising them, students can strengthen their understanding and build confidence for exams. This resource acts as a valuable guide in NIOS Class 12 Biology preparation, making revision effective and exam performance stronger.

NIOS Biology Chapter 28 Solutions

1. Differentiate between

(i) Marasmus and Kwashiorkor.

(ii) Rickets and Osteomalacia

(iii) Essential and non-essential amino acids

(iv) Body-building and protective foods.

(v) Water-soluble vitamins and fat-soluble vitamins.

(i) Marasmus and Kwashiorkor

Marasmus is caused by the deficiency of carbohydrates, fats, and proteins in infants below the age of one year.
Kwashiorkor develops when mothers stop feeding their babies with breast milk and the child is given traditional family food that has low protein in it.

(ii) Rickets and Osteomalacia

Rickets is a disease in children caused by calcium deficiency. The affected children will have soft bones, deformed or bent bones, bowed legs, pigeon chest, loss of tooth enamel, etc.
Osteomalacia is a calcium deficiency disease in adults, with symptoms of softening bones causing pain, and the bones tend to fracture.

(iii) Essential and non-essential amino acids

(a) Essential amino acids: These are the amino acids that can not be synthesised in the animal body and must be supplied with food, e.g., leucine.
(b) Non-essential amino acids: which can be synthesised in the body, particularly from carbohydrates, and need not be supplied in the diet. e.g. alanine.

(iv) Body-building and protective foods.

Bodybuilding foods: These are rich in proteins and help in the formation of new tissues. Example: legumes, milk, egg, meat, fish, pulses, nuts, and oilseeds.
Protective/regulatory foods: These are rich in minerals, vitamins, roughage, and water. They help in the regulation of internal metabolism in the body. Example: green leafy vegetables, fruits, amla, guava, citrus, oranges, and watermelon.

(v) Water-soluble vitamins and fat-soluble vitamins.

(a) Water-soluble vitamins are soluble in water. Examples are vitamins B complex and C
(b) Fat-soluble vitamins are soluble only in fat. Examples are vitamins A, D, E, and K

2. Give reasons why children of 1-5 years develop PEM.

PEM stands for Protein Energy Malnutrition. PEM is due to two reasons:

(a) Lack of proteins or carbohydrates or both in the diet.
(b) More intake of carbohydrates than proteins.

3. Why should one include more than one type of protein in the meals?

Intake of more than one plant protein in the same meal (dal-roti, sambar-idli) can produce a mixture containing all the essential amino acids. Essential amino acids are the amino acids that cannot be synthesised in the animal body and must be supplied with food.

4. What is the importance of water in the diet?

Water is an important constituent of our diet. 75% of an infant’s body and 60% of an adult’s body is nothing but water. Various functions of water are as follows.

Essential for the transport and digestion of food material.
Excretes waste.
Maintains the body temperature.
Acts as a solvent in various reactions in the body.

5. What is a balanced diet? Why do pregnant women or nursing mothers need

special diet?

A balanced diet contains all essential nutrients in suitable proportions and amounts to provide necessary energy and keep the body in a healthy state.

A balanced diet has the following qualities:

It meets the nutrient requirements of the body.
It consists of different types of food items.
It provides an adequate amount of energy.

A pregnant woman has to feed the developing embryo; therefore, she has a special need for extra nutrients. The pregnant women and lactating mothers should take,

(i) extra protein for tissue growth
(ii) more calcium and phosphorus to form bones of the baby
(iii) more iron for making sufficient blood for the baby
(iv) more carbohydrates for herself because extra energy is required to carry out all the building processes linked with the embryo.

6. Why should food contain roughage? Name two sources of roughage in our diet.

Roughage is the fibre present in some food items like fruits and vegetables. Though roughage is not a food, it forms an important part of our diet. Roughage consists mainly of cellulose.

Function

It helps with bowel movement.
It cleans our digestive tracts and protects the body from digestive ailments.
It prevents constipation.
It helps in retaining water in the body.
It helps in maintaining optimum levels of blood sugar and cholesterol.

E.g.. Fruits, beans, legumes.

7. Why is polishing of rice not advisable? If a person always consumes polished rice, what is he likely to suffer from? Give two symptoms.

Polishing the rice removes its nutritional layer, which contains some essential vitamins such as Vitamin B, thiamine.

Thiamine is required by the body; a deficiency of which can cause diseases such as beri-beri.
Polishing the rice increases its glycemic index, which can spike the blood sugar level.

8. State four important functions of food.

Food is any substance that performs the following functions in the body:

(i) yields energy for life processes,
(ii) builds up new cells during growth,
(iii) repairs worn-out (damaged) tissues,
(iv) aids in the production of useful body compounds.

9. If a child is not able to see in dim light, which two foodstuffs will you advise him to eat? Give reasons.

The child must take food that contains Vitamin A. Carrots and green leafy vegetables are good sources of this vitamin.

10. Name two sources rich in

(i) Vitamin A (ii) Calcium (iii) Iron

(iv) Vitamin B12 (v) starch (vi) Glucose

(i) Vitamin A: Carrots, sweet potatoes.
(ii) Calcium: Milk and spinach
(iii) Iron: Spinach, beef liver.
(iv) Vitamin B12: Milk and meat
(v) starch: Rice, potatoes
(vi) Glucose: Honey, dry fruits.

11. What are minerals? Name any two minerals and their sources.

Minerals are micronutrients required in varying amounts for proper functioning, normal growth, and maintaining good health of our body. They are inorganic elements, occurring in the form of their salts, e.g., calcium, potassium, sodium, phosphorus, iron, etc. They do not supply energy to our body, but are essential for protection against diseases and also have a role in body functions.

12. What are deficiency diseases? Name two diseases caused by the deficiency of proteins and carbohydrates. Also, write the symptoms of these deficiency diseases.

The diseases that occur due to a deficiency of one or more nutrients (proteins, carbohydrates, vitamins, and minerals) in our diet are called deficiency diseases.

(i) Marasmus, wasting of muscles, reduces the child to skin and bones.