Most of the choices appear to be          ones that you are familier with, but after taking          second look, you will find that they are different.

A．/; the

B．the; the

C．the; a

D．/; a

十二烷基磺酸钠(SDS)聚丙烯酰胺凝胶电泳过程中

A．分子体积最大的蛋白质最先洗脱下来

B．分子体积最小的蛋白质最先洗脱下来

C．不带电荷的蛋白质最先洗脱下来

D．带电荷的蛋白质最先洗脱下来