Primary immune response

Question 1

When an antigen enters the body for the first time, the small numbers of B-lymphocytes with receptors complementary to that antigen are stimulated to divide by mitosis
This is known as

Answer 1

clonal selection

Question 2

As these clones divide repeatedly by mitosis (the clonal expansion stage) the result is large numbers of

Answer 2

identical B-lymphocytes being produced over a few weeks

Question 3

Some of these B-lymphocytes become plasma cells that secrete lots of

Answer 3

antibody molecules (specific to the antigen) into the blood, lymph or linings of the lungs and the gut

Question 4

These plasma cells are short-lived (their numbers drop off after several weeks) but the antibodies they produce

Answer 4

the antibodies they have secreted stay in the blood for a longer time

Question 5

The other B-lymphocytes become memory cells that remain circulating in the blood for a long time

This response to a newly encountered pathogen is relatively

Answer 5

slow