肾调节血pH的主要机制是通过()
A.排出过多的酸和碱,调节血浆的碳酸盐含量
B.重吸收Na+和水
C.排出NH4
D.重吸收K+
E.重吸收Cl-
参考答案:A
下列动物不属于变温动物的是 ( )
A.鱼类
B.两栖类
C.爬行类
D.鸟类
----What about ____________ this afternoon?
----Sounds great. Let’s go __________ and buy some water first.
A.playing tennis; to shop
B.play tennis; to shop
C.playing tennis; shopping
D.play tennis; shopping