胡萝卜素是维生素A的前身,它在人体肠道和肝脏内,转化为维生素A。
参考答案:对
Her mother didn't ask him to do it, but she didn't ask him not to do it, ____. [ ]
A. too
B. also
C. either
D. as well
骨骼肌是机体最大的代谢器官,正常情况下,骨骼肌利用速度最快的能量来源是()
A.酮体
B.乳酸
C.葡萄糖
D.氨基酸
E.游离脂肪酸