PATHOLOGY

Detailed explanation-1: -Active immunity occurs when our own immune system is responsible for protecting us from a pathogen. Passive immunity occurs when we are protected from a pathogen by immunity gained from someone else.

Detailed explanation-2: -Active Immunity results when exposure to a disease organism triggers the immune system to produce antibodies to that disease. Active immunity can be acquired through natural immunity or vaccine-induced immunity.

Detailed explanation-3: -In antibody responses, B cells are activated to secrete antibodies, which are proteins called immunoglobulins. The antibodies circulate in the bloodstream and permeate the other body fluids, where they bind specifically to the foreign antigen that stimulated their production (Figure 24-2).

Detailed explanation-4: -An autoimmune disorder occurs when the body’s immune system attacks and destroys healthy body tissue by mistake. There are more than 80 types of autoimmune disorders.

Detailed explanation-5: -Antibodies are produced by the B lymphocytes. Germs and other substances that can provoke the creation of antibodies are also referred to as “antigens."