下列大分子中需要利用mRNA为模板进行合成的是( )。
A. 糖类
B. 脂类
C. 核酸
D. 蛋白质
鸡蛋煮熟后,蛋白质变性失活,这是由于高温破坏了蛋白质的( )
A. 肽键
B. 肽链
C. 空间结构
D. 分子量
细胞中有哪些脂质?举例说明它们在生命活动中的重要作用。(列出三种即可)
Watch theinterview with Audrey Hepburn and choose the best answer for the following questions.1. Before going to Ethiopia,Audrey Hepburn felt ________________.
A. nervous about what she's going to see
B. afraid of going there
C. emotionalabout what she's going to see
D. eager to go there