搜题请搜索小程序“爱下问搜题”
问题 单项选择题

HLA的遗传学特点包括（）

A.隐性遗传

B.双倍型遗传

C.共显性遗传

D.连锁平衡

E.显性遗传

答案

参考答案：C

解析：HLA的遗传学特点包括复等位基因，共显性遗传，单倍型遗传和连锁不平衡。

完形填空

请在II 栏中找出与I 栏格句子相对应的答语

I                                               II

小题1:What do you think of your English teacher ?   A  That sounds good.

小题2:How was your weekend?                         B  They’re 10 RMB.

小题3:Can I help you ?                              C  He is a policeman.

小题4:What does your father do ?                   D  She is nice and I like her.

小题5:Why do you like koalas?                      E  Yes, there is.

小题6:Thank you very much.                          F  A medium bowl.

小题7:Is there a post office near here?             G  It was great!

小题8:How much are the dumplings?                  H  Because they are cute.

小题9:What size bowl of noodles would he like?      I  You’re welcome.

小题10:Let’s go to the zoo!                       J  I’d like some dumplings, please.
查看答案
单项选择题

已知学生选课信息表：sc(sno，cno，grade)。查询“至少选修了一门课程，但没有学习成绩的学生学号和课程号”的SQL语句是

A．SELECT sno，cno FROM sc WHERE grade=NULL

B．SELECT sno，cno FROM sc WHERE grade IS”

C．SELECT sno，cno FROM sc WHERE grade IS NULL

D．SELECT sno，cno FROM sc WHERE grade="
查看答案