乳酸脱氢酶是一个由两种不同的亚基组成的四聚体。假定这些亚基随机结合成四聚体,可以组成同工酶的种类是()
A.两种
B.三种
C.四种
D.五种
E.六种
参考答案:D
按统计指标的作用和表现形式来划分,统计指标可分为()。
A.数量指标
B.总量指标
C.质量指标
D.相对指标
E.平均指标
The speaker announced that there was a big fire and directed _______ nearest the door to leave first. [ ]
A. that
B. them
C. those
D. these