题干

基因污染是指在天然物种的DNA中嵌入了人工重组基因,这些外来基因可随被污染生物的繁殖、传播而发生扩散。下列叙述错误的是()

A:基因工程间接导致了基因污染

B:基因工程破坏生物原有的基因组成

C:基因工程是通过染色体的重组发生基因交换,从而获得了生物的新性状

D:人类在发展基因工程作物时,没有充分考虑生物和环境之间的相互影响

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答案(点此获取答案解析)

C

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阅读填空 先通读下面的短文,然后根据短文内容,在文章后表格的空格内填入一个最恰当的单词。所填单词必须写在答题卡对应题号的横线上。每个空格只能填一个单词。

    A study shows that one million lives might be saved each year if people wash their hands with soap(肥皂) often. It also says that hand-washing with soap could be among the best ways to reduce diseases. Doctors say many diseases can be prevented from spreading by hand-washing. These include the common cold, influenza(流行感冒), hepatitis(肝炎), infectious diarrhea(腹泻) and so on.

    Doctors say you are easy to catch a cold by touching your nose or eyes after someone nearby has sneezed or coughed. Another reason to catch a disease is to eat food prepared by someone whose hands were not clean.

    They also say that hand-washing is especially important before and after preparing food, before eating and after using the toilet, after touching money and sneezing or coughing. The most helpful way is to wash them together while using soap and warm water. You do not have to use special soap. Be sure to wash all areas of the hands for about ten to fifteen seconds.

Title : Basic Knowledge of hand-washing

Diseases are

under ____.

People can____ many diseases from spreading by hand-washing such as the common cold, influenza and so on.

The____ of

becoming sick.

●Touch your nose or eyes after someone nearby has sneezed or coughed.

●Eat food prepared by____ hands.

____to do hand-washing.

●Before and after preparing food.

●Before eating and after using the toilet.

●After touching money and sneezing or coughing.

How to do

hand-washing.

●Wash them together while using soap and warm water.

●Wash all areas of the hands for about 10-15 seconds.