下列关于主动转运描述错误的是（）
A.需要载体
B.不消耗能量
C.结构特异性
D.逆浓度转运
E.饱和性
参考答案：B
解析：
主动转运有如下特点：
①逆浓度梯度转运；
②需要消耗机体能量，能量的来源主要由细胞代谢产生的ATP提供；
③主动转运药物的吸收速度与载体数量有关，可出现饱和现象；
④可与结构类似的物质发生竞争现象；
⑤受代谢抑制剂的影响，如抑制细胞代谢的二硝基苯酚、氟化物等物质可以抑制主动转运；
⑥主动转运有结构特异性，如单糖、氨基酸、嘧啶及某些维生素都有本身独立的主动转运特性；
⑦主动转运还有部位特异性。
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