水溶性葡萄糖由胃肠道进入血液,并由血液进入神经组织的一系列通过生物膜的方式()
A.简单扩散
B.滤过
C.主动转运
D.异化扩散
E.膜动转运
参考答案:D
若点A(1-2a,a-2)关于原点的对称点在第一象限,则a的整数解有( )
A.1个
B.2个
C.3个
D.4个
用所给词的适当形式填空。
1. I don't have much time (play) with my friend.
2. Thank you very much for (write) to me.
3. Every day Millie spends half an hour (study) English.
4. Lily always helps her mother (clean) the house.
5. Daniel (not want) a new computer.