試題詳解

76. (1) Ribozyme； (2) Okazaki fragment； (3) DNA polymerase needs an RNA primer but RNA polymerase doesn’t； (4) de novo biosynthesis of purine and pyrimidine； (5) retrovirus； (6) thermostable DNA polymerase. How many of the preceding items support the hypothesis that RNA appears before DNA?
(A) 2
(B) 3
(C) 4
(D) 5
(E) 6