IMMUNOLOGY

Detailed explanation-1: -They help your immune system fight germs and protect you from disease. There are two main types. Cytotoxic T-cells destroy infected cells. Helper T-cells send signals that direct other immune cells to fight infection.

Detailed explanation-2: -Killer T-cells find and destroy infected cells that have been turned into virus-making factories. To do this they need to tell the difference between the infected cells and healthy cells with the help of special molecules called antigens. Killer T-cells are able to find the cells with viruses and destroy them.

Detailed explanation-3: -T cells can detect the presence of an intracellular pathogen because infected cells display on their surface peptide fragments derived from the pathogen’s proteins. These foreign peptides are delivered to the cell surface by specialized host-cell glycoproteins.