Question

Cells have two primary methods to defend against invading pathogens. They are cell-mediated immunity and humoral immunity. Why are two separate methods needed to defend the body against invading pathogens?

Answer 1

The T cells and B cells are the major components of adaptive immune system. The T cells involve in cell mediated immunity, whereas the B cells involve in humoral immunity (antibody mediated immunity).

The main function of these two cells is to recognize ‘foreign particles’ or ‘non-self-antigens’ during the process of antigen presentation.

✓there are two types of defenses against foreign invaders: specific and nonspecific. Specific immune responses can distinguish among different invaders. The response is different for each invader. With nonspecific defenses, the protection is always the same, no matter what the invader may be. Whereas only vertebrates have specific immune responses, all animals have some type of nonspecific defense. Examples of nonspecific defenses include physical barriers, protein defenses, cellular defenses.