细胞松弛素B能引起植物原生质体排核，因此可以获得胞质体。
参考答案：对
—Did your parents go to the film yesterday evening?
—No. We ______ stayed at home watching TV. [ ]
A. both
B. all
C. either
D. none
斗轮堆取料机分为斜坡取料和平坡取料及陡坡取料三种。（）
