AP BIOLOGY

Detailed explanation-1: -immunisation by taking vaccines. Vaccines provide immunity from infectious diseases like tetanus, diphtheria, whooping cough, measles, polio etc. Our body has an immune system which fights microbial infection. When this system first sees an infectious microbe, it kills the microbe and remembers it.

Detailed explanation-2: -Natural immunity is acquired from exposure to the disease organism through infection with the actual disease. Vaccine-induced immunity is acquired through the introduction of a killed or weakened form of the disease organism through vaccination.

Detailed explanation-3: -Humans have three types of immunity-innate, adaptive, and passive: Innate immunity: Everyone is born with innate (or natural) immunity, a type of general protection. For example, the skin acts as a barrier to block germs from entering the body.

Detailed explanation-4: -Another critical component of vaccination is that it helps produce memory B-and T-cells that are specific to the virus. Like an army reserve force, these immune cells can be quickly activated in the future to produce antibodies to stop the virus from invading your body. And unlike antibodies, these cells persist.