题目

_______you’ve got a chance, you might as well make full use of it.    A. Now that  B. After   C. Although   D. As soon as   答案：Anow that 表示“既然”。  ATP是细胞内的能源物质，医药商店出售的ATP注射液可治心肌炎。若人体静脉滴注这种药物，ATP到达心肌细胞内最少要通过的细胞膜有A．1层　　B．2层　C．3层　D．4层