IMMUNOLOGY

Detailed explanation-1: -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-2: -Vaccines prompt the immune system to make disease-fighting antibodies, which give you the benefit of acquired immunity without having to get sick first. They do this by introducing antigens in the form of an inactivated or killed virus into the body in order to stimulate the immune system.

Detailed explanation-3: -The innate immune responses are the first line of defense against invading pathogens. They are also required to initiate specific adaptive immune responses. Innate immune responses rely on the body’s ability to recognize conserved features of pathogens that are not present in the uninfected host.

Detailed explanation-4: -A prominent difference between active and passive immunity is that active immunity is developed due to the production of antibodies in one’s own body, while passive immunity is developed by antibodies that are produced outside and then introduced into the body.

Detailed explanation-5: -Some pathogens induce a normal immune response but have evolved specialized mechanisms for resisting its effects. For instance, some bacteria that are engulfed in the normal way by macrophages have evolved means of avoiding destruction by these phagocytes; indeed, they use macrophages as their primary host.