AP BIOLOGY

Detailed explanation-1: -Antibodies attach to a specific antigen and make it easier for the immune cells to destroy the antigen. T lymphocytes attack antigens directly and help control the immune response. They also release chemicals, known as cytokines, which control the entire immune response.

Detailed explanation-2: -T lymphocytes are part of the immune system and develop from stem cells in the bone marrow. They help protect the body from infection and may help fight cancer.

Detailed explanation-3: -There are two main types of lymphocytes: B cells and T cells. The B cells produce antibodies that are used to attack invading bacteria, viruses, and toxins. The T cells destroy the body’s own cells that have themselves been taken over by viruses or become cancerous.

Detailed explanation-4: -When the perfectly shaped virus antigen on an infected cell fits into the Killer T-cell receptor, the T-cell releases perforin and cytotoxins. Perforin first makes a pore, or hole, in the membrane of the infected cell. Cytotoxins go directly inside the cell through this pore, destroying it and any viruses inside.

Detailed explanation-5: -Helper T-cells stimulate B-cells to make antibodies and help killer cells develop. Killer T-cells directly kill cells that have already been infected by a foreign invader.