问题 问答题 简答题

什么是抗原?什么是抗体?

答案

参考答案:抗原——是指能刺激机体产生特异性免疫反应,并能与相应的免疫应答产物(抗体)在体内或体外发生特异性结合的物质。如细菌、病毒、立克次体等。抗体——是指B淋巴细胞在抗原刺激下转化为浆细胞,所产生的特异性的免疫球蛋白,是能与抗原发生特异性结合的物质,它存在于血清、体液及黏膜分泌液中,是构成人体内体液免疫的主要物质。

阅读理解

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.   小题1:   .

Body image is a person’s opinions and feelings about his or her own body and physical appearance.    小题2:   . You appreciate your body for its capabilities and accept its imperfections.

So, what can you do to develop a positive body image? 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.     小题3:   .

Exercise regularly. Exercise can help you look good and feel good about yourself. Good physiques (体形) don’t just happen.    小题4:   . A healthy habit can be as simple as exercising 20 minutes to one 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.

  小题5:     . 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.They care just as much as girls do about their body image.

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

单项选择题 A1型题