How are humans able to produce billions of unique B and T cell receptors?
a. Each time a pathogen is encountered, a new receptor is produced.
b. The two different genes that encode receptor proteins, allow for many versions of receptors to be produced.
c. Random splicing of gene segments encoding receptor proteins allows for 2.5 billion potential combinations.
d. Antigen presenting cells stimulate B and T cells to each produce billions of receptor molecules.
e. There are billions of B and T cells, each of which produces a single receptor on its cell surface.
ANSWER: c
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