Primary Immune response

Question 1

cell mediated immunity

Answer 1

macrophage engulf pathogens partially digest um.

antigen presentation.

specific binding of T helper cells w complementary shaped receptor *clonal selection. produce interleukins stimulate more T cells divide by mitosis. *clonal expansion.

cloned T cells may:

develop into T mem
produce interleukins which stimulate phagocytosis.
produce interleukins that stimulate B cells to divide.
develop into T killer cells and destroy infected cells.

Question 2

Humoral immunity

Answer 2

B lymphocyte binds to pathogen with complementary shaped antigen, engulfs it and processes the antigen and becomes an APC.

T helper bind to the B cell APC *clonal selection

Interleukins from t helper activate the B cells.

activated B cells divide by mitosis to give clones of plasma cells and B memory cells *clonal expansion.

cloned plasma cells produce antibodies that fit the antigen on th surface of the pathogen. they act as opsonins or agglutinins.

some cloned B cells develop into B memory cells.

Question 3

during a primary immune response

Answer 3

symptoms are usually seen because the pathogen has had the time to reproduce and do damage as clonal selection takes time.