Question

Question 1

B cells have antigen receptors that bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells. Cytotoxic T cells have antigen receptors that

• are active only in lymph nodes.
• bind only to antigens present on the surface of the invading/foreign cells.
• bind only to freely dissolved antigens in the plasma.
• bind to antigen fragments presented on major histocompatability complexes by host cells.
• bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells.

Answer 1

ANSWER:- Option 4 is correct. Cytotoxic T cells have antigen receptors that bind to antigen fragments presented on major histocompatability complexes by host cells.

Cytotoxic T-cells are called CD8+ T cells.These cells express T cell Receptors(TCR) that recognize a specific antigen which are bound with Major Histocompatibility Complexes I (MHC I) on surface of host cells. Cytotoxic cells thus only bind to antigens if presented on MHC I on Antigen presenting cells.