题干

下列与遗传变异有关的叙述,正确的是(    )

A:《婚姻法》规定禁止近亲结婚,是因为该项措施能降低某些遗传病的发病率

B:基因重组可以通过产生新的基因,表现出性状的重新组合

C:三倍体无子西瓜的培育过程,运用了生长素促进果实发育的原理

D:若DNA中某碱基对改变,则其控制合成的蛋白质分子结构肯定会发生改变

上一题 下一题 0.0难度 选择题 更新时间:2019-12-16 10:45:22

答案(点此获取答案解析)

A

同类题1

任务型阅读

    Maybe you are an average student. ____ This is not necessarily so, however. Anyone can become a better student if he or she wants to. Here's how.

    Plan your time carefully. When planning your work, you should make a list of things that you have to do. After making this list, you should make a schedule of your time. First your time for eating, sleeping, dressing, etc. Then decide a good, regular time for studying. ____ A weekly schedule may not solve all your problems, but it will force you to realize what is happening to your time.

    Make good use of your time in class. ____ Listening carefully in class means less work later. Taking notes will help you remember what the teacher says.

    Study regularly. When you get home from school, go over your notes; look at the important points that your teacher is going to discuss the next day, read that material. ____ If you do these things regularly, the material will become more meaningful, and you'll remember it longer.

    Develop a good attitude towards tests. The purpose of a test is to show what you have learned about a subject. They help you remember your new knowledge. The world won't end if you don't pass a test, so don't be over worried.

    ____ You will probably discover them after you have tried these.

A. There are other methods that might help you with your studying.

B. Don't forget to set aside enough time for relaxation.

C. Take advantage of class time to listen to everything the teacher says.

D. No one can become a top student unless he or she works hard.

E. You probably think you will never be a top student.

F. Make full use of class time to take notes of what the teacher says in class.

G. This will help you understand the next class.