試題詳解

2. How does the immune system produce so many different antibodies?
(A) vertebrates inherit millions of different antibody genes
(B) each antibody is the product of several different genes that are shuffled to produce new combinations
(C) meiotic recombination and independent assortment lead to antibody variations
(D) the immune system creates new B cells each time it is exposed to a new antigen
(E) all of the above