ANATOMY

Detailed explanation-1: -Killer T cells (cytotoxic T lymphocytes) attack other cells. They are particularly useful for fighting viruses. They work by recognizing small parts of the virus on the outside of infected cells and destroying the infected cells.

Detailed explanation-2: -Helper T-cells play the main role in coordinating an immune response once a foreign enemy has been spotted. If a T-cell in the thymus acquires a protein marker known as CD4, it becomes a helper T-cell.

Detailed explanation-3: -RB: T cells can play different roles. They can act as “killer cells”, attacking cells which have been infected with a virus or another kind of pathogen, or they can act as “helper cells” by supporting B cells to produce antibodies.

Detailed explanation-4: -Cytotoxic T-cells kill cells infected with viruses and bacteria, and they also destroy tumor cells. Helper T-cells: Helper T-cells are also called CD4+ cells because they have a CD4 receptor on their membranes.