5.4 Humoral Immunity And B Lymphocytes

Question 1

What happens in the primary immune response ?

Answer 1

~plasma cells secrete antibodies into the blood plasma to destroy the antigen.
~ memory cells and antibodies are produced. The memory T cells remain in the body for a long time and remember the specific antigen
~ the person is now immune to the infection

Question 2

What is the secondary immune response

Answer 2

~Memory B cells are activated and divide into plasma cells which produce the complementary antibody to the antigen and Memory T cells are activated to divide into T cells to kill the cell carrying the antigen.
~ Secondary immune response is much faster as clonal selection happens faster.

Question 3

How are clones of B lymphocytes produced?

Answer 3

~antigen enters the blood , and attaches to the complementary antibodies on the surface of a specific B cell
~ the antigen enters the B cell by endocytosis and the antigen is then presented on the surface of the B-cell
~ T(h) cells bind to these presented antigens and stimulate B cells which divide by mitosis and form a clone of identical B cells which produce the antibody that is specific to the foreign antigen ( clonal selection)

Question 4

How are B lymphocytes involved in humoral immunity?

Answer 4

~ the antigens on the surface of the invading pathogen are taken up by B-cells
~ the B cell processes the antigen and presents the them on its surface
~ T (h) cells are activated and attach to the processed antigens on the B cell , activating the B cell
~Activated B-cell divides by mitosis and differentiates to forms a clone of plasma cells, which produce and secrete a specific antibody which is complementary to the antigen on the pathogen surface.
~ antibody attaches to the surface antigen and destroys them