第3题: [单项选择]Questions 11 to 18 are based on the conversation you have just heard. A. She was considerate. B. She was unforgiving, C. She was apologetic. D. She was sympathetic. 参考答案:B 答案解析:[听力原文] M: I’m really sorry I didn’t make it to your dinner party last night, Julie. W: It’s al
第19题: [多项选择]高等动物胆汁酸的结构特点为 A. 是甾类化合物,具甾体母核 B. 17位连有β-戊酸侧链 C. 为三萜类化合物 D. 17位有不饱和内酯环 E. 多与甘氨酸或牛磺酸以酰胺键结合,并以钠盐形式存在 参考答案:A,B,E 答案解析:[解题思路] 在高等动物的胆汁中胆汁酸是一类24个碳原子的胆烷酸的衍生物,存在于动物胆汁中。鱼类和两栖类、爬行类动物的胆汁酸为27或28个碳原子。