試題詳解

3. Which of the following is true for both prokaiyotic and eukaryotic gene expression?
(A) after transcription, a 3,poly-A tail and a 5，cap are added to mRNA
(B) transcription of mRNA can begin before transcription is completed
(C) RNA polymerase may recognize a promoter region upstream from the gene
(D)mRN'A is synthesized in the 3direction
(E) the mRNA transcript is the exact complement of the gene from which it was copied