不属于参与细胞内信息传递的第二信使物质是（）。
A.cAMP
B.钙离子
C.IP3
D.DAG
E.ATP
参考答案：E
—You ____ have set aside more time to play with our kids.
—I wish I ______, but you know how busy I was.
A．should, would
B．could, did
C．might, should
D．should, had
不合理运输的最严重形式是过远运输。（）
