题目

 “Do you regret paying 500 dollars for that work of art?”    “No, I __________ twice as much for it.”    A. had gladly paid                    B. will gladly pay C. will have gladly paid                D. would have gladly paid 答案：D合成肽链时，出现正常的肽链终止，是因为 [     ]A．一个与mRNA链终止密码相应的tRNA不能携带氨基酸 B．不具有与mRNA链终止密码相应的反密码子tRNAC．mRNA在mRNA链终止密码处停止合成D．tRNA上出现终止密码