题目

丙氨酸的R基为﹣CH3,谷氨酸的R基为﹣C3H5O2,它们缩合形成的二肽分子中,C、H、O的原子比例为()      A. 7:16:6                     B. 7:14:5               C.   8:12:5       D. 8:14:5 答案:D(   ) 1. —Jenny,I hear there will be an art club in our school.       —Wonderful!I can't wait to         it.   A. repeat   B. forget   C.  receive   D. join
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