问题 单项选择题

R质粒的叙述正确的是( )

A.R质粒是编码细菌非耐药性的基因

B.一种R质粒只含有针对一种抗生素的耐药基因

C.R质粒可分为接合性R质粒和非接合性R质粒

D.接合性R质粒是由非耐药传递因子和非耐药决定因子组成

E.非接合性R质粒不能转化或转导方式进入受体菌

答案

参考答案:C

解析: R质粒带有一种或多种耐药基因。

选择题
完形填空

Section C

Directions:  Read the following text and choose the most suitable heading from A-F for each paragraph.  There is one extra heading which you do not need.

76.

Even if you do not live in a country where English is the main language. You can take advantage of many opportunities to practice reading in English. By taking advantage of a wide variety of sources, you will come to appreciate the richness and variety of styles that individuals will use to express themselves.

77.

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78.

If you are not interested in classical literature, perhaps it does not make much sense to force yourself to read these materials. Fortunately, there are millions of books written in English. As an example, if you enjoy water painting you may want to purchase a book about it Written in English.

79.

Chances are, if there is a hobby you are interested in, there are authors writing something about it in English. If you search the web, it should be fairly easy to locate websites that have free newsletters. These materials are ideal because they provide you with fresh reading materials. In addition, because they are about a topic that you already know something about, you will be able to appreciate the information that is shared, as well as practice your reading skills.

80.

Unlike a few years ago, you can have access to news in English whenever you want. If you are interested in particular area of the world, you may even want to use your time to read those sections of the news. In most cases, you can find free news resources on the Internet. These may also be an excellent place for you to find the names of other websites that have additional information that you might be interested in.