IMMUNOLOGY

Detailed explanation-1: -Antibodies. Antibodies help the body to fight microbes or the toxins (poisons) they produce. They do this by recognising substances called antigens on the surface of the microbe, or in the chemicals they produce, which mark the microbe or toxin as being foreign. The antibodies then mark these antigens for destruction.

Detailed explanation-2: -The damaged cells release chemicals including histamine, bradykinin, and prostaglandins. These chemicals cause blood vessels to leak fluid into the tissues, causing swelling. This helps isolate the foreign substance from further contact with body tissues.

Detailed explanation-3: -Antibodies can quickly detect germs and other potentially harmful substances, and then attach to them. This neutralizes the “intruders” and attracts other immune system cells to help. Antibodies are produced by the B lymphocytes.

Detailed explanation-4: -Antibodies, also known as immunoglobulins, are proteins that attach themselves to pathogens. This signals immune cells to destroy the pathogen.

Detailed explanation-5: -antigen, substance that is capable of stimulating an immune response, specifically activating lymphocytes, which are the body’s infection-fighting white blood cells. In general, two main divisions of antigens are recognized: foreign antigens (or heteroantigens) and autoantigens (or self-antigens).

Detailed explanation-6: -Tetanus, diphtheria and scarlet fever are all diseases where the bacteria secrete toxins. Once the invading microbes have been destroyed the immune response winds down. Once a person has had a disease they don’t normally catch it again because the body produces memory cells that are specific to that antigen.