問題詳情
45. The exceptionally large diversity of antigen receptors found on B cells and T cells is mostly the result of
(A)alternate splicing.
(B)random mutations.
(C)gene amplification.
(D) recombinase activity.
(E)clonal selection.
(A)alternate splicing.
(B)random mutations.
(C)gene amplification.
(D) recombinase activity.
(E)clonal selection.
參考答案
答案：D
難度：困難0.25
統計：A(9),B(2),C(2),D(8),E(6)
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