题目

由下列结构片段组成的蛋白质在胃液中水解，不可能产生的氨基酸是A ．           B．H2NCH2COOHC．     D．  答案：D解析:氨基酸缩合形成肽键。多肽水解时，肽键在断裂。所以自左向右生成的氨基酸是A、H2NCH2 CH2COOH、A、C、B。所以答案选D。 交际英语 从A~G选项中选出能填入空白处的最佳选项，补全对话（有两项是多余的）。 A: Amy, 1 B: I usually go to basketball practice. Do you like basketball? A: Yes, I do. 2 B: We play games every Saturday. 3 A: I often watch movies on Saturdays. I also practice the drums. B: Really? 4 A: Yes, I practice every day. B: 5 1．________ 2．________ 3．________ 4．________ 5．________