①精子与卵细胞、极核融合 ②花粉管进入子房 ③花粉管进入胚珠
④花粉萌发出花粉管. ⑤花粉管末端破裂释放出精子.
A:④②③⑤①
B:②④③⑤①
C:①②③④⑤
D:④⑤②③①
1984年在第26届奥运会上我国实现了奥运金牌零的突破。( )
Dream of the Red Mansions is more than novel. It can help us understand social life of that time.
如图,MC∥AB,NC∥AB,则点M,C,N在同一条直线上,理由是____