B-lymphocytes and humoral immunity

Question 1

where do B-lymphocytes mature?

Answer 1

in bone marrow

Question 2

how is the correct B-cell for the invading pathogen selected?

Answer 2

when an antigen (either from an APC or a free floating antigen e.g. virus or toxin) binds to the complementary B cell receptor site

Question 3

how are B-cells activated?

Answer 3

has to be activated by a Helper T-cell that was produced in response to the same antigen

once the APC phagocyte and the helper T-cell have bound to the B cell then a cytokine (interleukin-1) is released and the B cell starts to clone

whole process is called CLONAL SELECTION THEORY

Question 4

what do the clone of B-cells differentiate into?

Answer 4

memory B cells and plasma B cells

Question 5

what is the role of plasma B cells?

Answer 5

produce antibodies known as primary immune response

Question 6

where do memory cells go?

Answer 6

they have a long life span and can stay in the lymphatic and circulatory system, and in the tissue fluid

Question 7

what do memory B-cells do when they come across an antigen for the second time? (secondary response)

Answer 7

they are able to independently cone and rapidly produce plasma B-cells

this means antibodies can be produced quicker in larger quantities than in the primary response

any pathogens are killed before disease-like symptoms develop

in this way, the memory cells provide long-term immunity