题干

下列叙述错误的是                              

A:将两匹奔跑速度快、耐力持久的种马交配,所生小马一定能继承“双亲”的特征,不仅跑的快,而且耐力持久。

B:选择育种是一种古老的育种方法,它的局限性在于进展缓慢,可选择的范围有限。

C:人工诱变是创造动植物新品种和微生物新类型的重要方法,它突出的优点是可以提高突变率,加速育种的进程。

D:对于基因工程或分子生物学实验室向外排放转基因细菌等必须严加管制。

上一题 下一题 0.0难度 选择题 更新时间:2019-08-09 10:10:42

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A

同类题1

选择合适的选项补全短文。

    Although problems are a part of our lives, it certainly doesn't mean that we let them rule our lives forever. One day or the other, you'll have to stand up and say - problem, I don't want you in my life.

    ____ Problems with friends, parents, girlfriends, husbands, and children - the list goes on. Apart from these, the inner conflicts within ourselves work, too. These keep adding to our problems. Problems come in different shapes and colors and feelings.

    But good news is that all problems can be dealt with. Now read on to know how to solve your problems.

    Talk, it really helps. What most of us think is that our problem can be understood only by us and that no talking is going to help.____ Talking helps you move on and let go.

    Write your problems.____ When you write down your problems, you are setting free all the tension from your system. You can try throwing away the paper on which you wrote your problems. By doing this, imagine yourself throwing away the problems from your life. Don't lose faith and hope. No matter what you lose in life, don't lose faith and hope. Even if you lose all your money, family… you should still have faith.____

    Your problems aren't the worst. No matter what problem you get in life, there're another one million people whose problems are huger than yours,____ Your problems might just seem big and worse, but in reality they can be removed.

    Go about and solve your problems because every problem, however big or small, always has a way out.

A. But the truth is that when you talk about it, you're setting free the negative energies that have been gathering within you.

B. When we have a problem, a pressing, critical, urgent, life-threatening problem, how do we try and solve it?

C. Tell yourself: when they can deal with them, why can't I?

D. Of course, we've been fighting troubles ever since we were born.

E. We can often overcome the problem and achieve the goal by making a direct attack.

F. Having a personal diary can also be of huge help if you don t want a real person to talk with.

G. With faith and hope, you can rebuild everything that you lose.