下列能自由透过线粒体膜的物质是
A．NADH
B．草酰乙酸
C．脂酰CoA
D．磷酸二羟丙酮
E．乙酰CoA
参考答案：D
解析： 只有磷酸二羟丙酮能自由透过线粒体膜。NADH需经苹果酸天冬氨酸穿梭作用或α磷酸甘油穿梭作用转运。草酰乙酸可转变成天冬氨酸或苹果酸等冉透过线粒体膜。乙酰CoA需借助枸橼酸-丙酮酸循环转运。而脂酰CoA要由肉碱携带穿过线粒体内膜。
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