组成人体蛋白质多肽链的基本单位是( )
A.L-α氨基酸B.D-α氨基酸C.L-β氨基酸D.D-β氨基酸E.以上都不是
参考答案:A
汽机主控系统的三种控制方式分别为()、()和()。
How is Mr Brown?()
A.He is tall and beautiful
B.He is very strict with us
C.He is fine
D.He is in an expensive car