20. Adaptive Immunity

_________ is another name for antibodies.

An antibody's variable region:

1. Varies in amino acid sequence to allow different antibodies to bind different antigens.
2. Is located in the hinge and stem regions of an antibody.
3. Is a portion of the light chain of an antibody.
4. Is a portion of the heavy chain of an antibody.

Genetic recombination frequently occurs in the body’s B cell population. Why is this advantageous to the 

immune system?

DRAW IT

a. In the following graph, at time A the host was injected with tetanus toxoid. Show the response to a booster dose at time B.

b. Draw the antibody response of this same individual to exposure to a new antigen at time B.

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