促使轴突末梢释放神经递质的离子是()。
A.K+
B.Na+
C.Ca2+
D.Cl-
E.H+
参考答案:C
—Can you give some advice on what I said just now?
—Sorry. My mind______________.
A.is wandering
B.was wandering
C.has wandered
D.had wandered
单性状育种估计中回归系数bAP的计算式并简要说明。