Evolving an Immune Response
Antibodies stick very specifically to foreign molecules. Take 2 weeks to develop.
The body has hundreds of millions of B-cells each of which make an antibody from a randomly spliced together section of DNA.
B-cells which make antibodies that stick to your own molecules are killed off during development.
B-cells that make antibodies that stick to an invader are ‘activated’ – start dividing rapidly, and undergoing further mutation and selection in regions coding for antibodies.