题干

下列属于不可遗传变异的是(   )

A:视觉正常的夫妇生下的患色盲的儿子

B:大蒜在无光条件下长成的蒜黄

C:一窝家兔中白色、黑色、灰色的个体

D:甜玉米的果穗上出现的非甜玉米籽粒

上一题 下一题 0.0难度 选择题 更新时间:2019-03-04 06:15:54

答案(点此获取答案解析)

B

同类题3

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。

    Many people think of guys as being carefree when it comes to their appearance. But in fact, a lot of guys spend plenty of time in front of the mirror. They care just as much as girls do about their body image.

    Body image is a person's opinions and feelings about his or her own body and physical appearance. ____You appreciate your body for its capabilities and accept its imperfections.

    ____Here are some ideas.

    Recognize your strengths. Different body types are good for different things. What does your body do well? Maybe your speed, strength, or coordination makes you better than others at a certain sport. That may be basketball, table tennis, mountain biking, dancing, or even running. Or perhaps you have non-sports skills, like drawing, painting, singing, playing a musical instrument, writing, or acting. ____

    Exercise regularly. Exercise can help you look well and feel good about yourself. Good physiques (体形) don't just happen.____ A healthy habit can be as simple as exercising 20 minutes to 1 hour three days a week. Working out can also lift your spirits.

    Respect your body! Practicing good habits regular showering; taking care of your teeth, hair, and skin; wearing clean clothes, and so on can help you build a positive body image.

    ____Your body is just one part of who you are. Your talent for comedy, a quick wit (智慧) and all the other things make you unique. So try not to let small imperfections take over.

A. Use this as an opportunity to discover what you're good at.

B. Be yourself.

C. Having a positive body image means feeling satisfied with the way you look.

D. Just explore talents that you feel good about.

E. They take hard work, regular workouts, and a healthy diet.

F. The good news is that self-image and body image can be changed.

G. So, what can you do to develop a positive body image?