ANATOMY

Detailed explanation-1: -They use chemical messengers to activate other immune system cells in order to start the adaptive immune system (T helper cells). They detect cells infected by viruses or tumorous cells and destroy them (cytotoxic T cells).

Detailed explanation-2: -Neutrophils are typically the first cells to arrive at the site of an infection because there are so many of them in circulation at any given time.

Detailed explanation-3: -Numerous cells are involved in the innate immune response such as phagocytes (macrophages and neutrophils), dendritic cells, mast cells, basophils, eosinophils, natural killer (NK) cells and innate lymphoid cells. Phagocytes are sub-divided into two main cell types: neutrophils and macrophages.

Detailed explanation-4: -B lymphocytes become cells that produce antibodies. 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.

Detailed explanation-5: -Helper T-cells are a type of immune cell. When they sense an infection, they activate other immune cells to fight it. They may activate cytotoxic T-cells or they may activate B-cells, which produce antibodies. Your helper T-cells are one the most important types of cells involved in your adaptive immune response.