最常见的蛋白质化学修饰是
A．脂酰化和去脂酰化
B．乙酰化和去乙酰化
C．甲基化和去甲基化
D．腺苷化和去腺苷化
E．磷酸化和去磷酸化
参考答案：E
根据所给图片完成下面的语段。
Today is Sunday. My family are all at home. We would like to do housework. My father can
_____________ and _____________ . My mother can _____________
and _____________ . I can _____________ and empty the trash. We are helpful.
试压时，先将（）系统中的阀门全部打开，通大气的管道封死。
A．氧气管道
B．热力管道
C．空气管道
D．输油管道
and _____________ 
. My mother can _____________ 
. I can _____________ 
and empty the trash. We are helpful.