Question

How does the body defend against invasion?

Answer 1

1. Invasion: It has been defined as the processes by which an organism is introduced to and establishes a sustainable population in a region beyond its native geographical range.
2. The body defends against an invasion by following methods-

1. Skin and mucous membrane barriers- The skin physically prevents microorganisms from entering the body.
2. Nonspecific internal defenses such as phagocytosis, natural killer cell killing, inflammation, and fever.
3. iii. Immunological response- Fever is due to endogenous pyrogens, chemical substances launched through white blood cells in reaction to infection. High temperatures inhibit the bacterial immune reaction.