神经元的功能是:接受刺激后能够( )。
A:产生兴奋
B:引起肌肉收缩
C:产生感觉
D:产生兴奋、传导兴奋
生物实验中,为观察细胞结构或鉴定细胞内物质,常进行染色、脱色或加入物质呈现颜色变化.如图是教材实验组与此有关的操作.请据图回答:
It was not until dark ___ he was aware of ___ he thought was the correct way to solve the problem.