题干

雷(P.M.Ray)将燕麦胚芽鞘切段放入一定浓度生长素的溶液中,发现10~15min后切段开始迅速伸长,同时溶液的pH下降,细胞壁的可塑性增加。将胚芽鞘切段放入不含生长素的pH3.2~3.5的缓冲溶液中,则1min后可检测出切段的伸长,且细胞壁的可塑性也增加;如将切段转入pH7的缓冲溶液中,则切段的伸长停止;若再转入pH3.2~3.5的缓冲溶液中,则切段重新表现出伸长。基于上述结果,雷和克莱兰于1970年提出了生长素作用机理的酸生长理论。下列相关叙述错误的是(  )

A:细胞膜上存在着运输H的载体,生长素使其活化

B:生长素作用于细胞后,细胞将H通过协助扩散运出细胞

C:给植物细胞提供酸性环境,不需生长素也可生长

D:应用生长素处理切段后,溶液中H浓度会增加

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B

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