问题 单项选择题

LD是由2种亚基组成的四聚体,共形成几种同工酶

A.2种

B.3种

C.4种

D.5种

E.6种

答案

参考答案:D

解析:本题考查LD的同工酶,LD是由2种不同的亚基(M、H)构成的四聚体,形成5种同工酶,即LDl(H4)、LD2(H3M)、 LD3(H2M2)、LD4(H3M)、LD5(M4)。

情景交际
完形填空

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Currently, there is a growing recognition that parental involvement is one key to student achievement.小题1:_____.However, while these may be important for developing a sense of community and parental ownership of the school and its issues, such activities do not translate directly to students achievement.

小题2:_____.Simply asking the question,” So, what did you do in school today?” can start a discussion between parent and child about topics studied in class.Even talks at home about less classroom-specific topics that interest the student are shown to be important to raising student achievement.小题3:____.Teachers can provide students with interesting ideas for starting school-related conversations at home.小题4:____.

The school’s focus should be on how to enable parents and their children to have such meaningful conversations about the topics and ideas flowing from the classroom.小题5:_____.

Finding ways to promote direct parent participation in their children’s lives-at school and at home will have a much greater impact.

A.Some parents expect too much of their children

B.Teenagers can have rich and interesting conversations if encouraged

C.Starting a parent council may not be a top priority

D.Many schools have attempted to find ways for parents to participate in school management by setting up parent councils for parents to volunteerE.Self-education plays an important role in children’s development

F.Another way for parents to be more active in their children’s education pays dividents

G.Telling children that school is valuable is a lot less effective than showing them it is by being involved in what they are doing there.