Q16 of 328 Page 297

Why is immune system essential for our health?

Immune system is body defence system against various types of pathogens. It includes following components off blood-phagocytic cells, natural killer cells (NK cells), T-lymphocytes and B-lymphocytes. B-lymphocytes produce antibodies against antigens of pathogens and their toxins. Immune system keeps the body healthy by killing infecting microbes. Immune system keeps us healthy by saving us from diseases.


More from this chapter

All 328 →
14

Explain giving reasons.

(a) Balanced diet is necessary for maintaining healthy body.


(b) Health of an organism depends upon the surrounding environmental conditions.


(c) Our surrounding area should be free of stagnant water.


(d) Social harmony and good economic conditions are necessary for good health.

 15

What do you mean by disease symptoms? Explain giving two examples.

 17

Why is AIDS considered to be a “syndrome” and not a disease?

 18

Why do some children fall ill more frequently than others living in the same locality?