Sometimes we might even need to spend some time making a request.

You are probably familiar with the saying：An apple a day keeps the doctor away. A recent research carried out by the Chinese University of Hong Kong may change the saying:
An apple a day may keep aging away.
The research chose fruit flies(果蝇), as they share many genes(基因)with humans. The fruit flies were either fed normally or had an apple extract(浓缩物) added to their diet.
It turned out that those fruit flies that were given apple extract lived about 55 days—five days longer than the flies that were normally fed. The research group also found it easier for the flies to walk，climb and move about as they aged.
According to the result, the researchers believed that the antioxidants(抗氧化剂) in the apple extract helped clean up dangerous chemicals(化学物质) that cause illnesses，as well as aging.
In another study，researchers examined diets of thousands of women. They discovered that those who regularly ate apples were 20 percent less likely to suffer heart illnesses and stroke.
The apples’ genetic code(遗传密码) was discovered recently. It allows scientists to develop nicer and healthier fruits. Researchers are already using the information to grow a kind of apples full of antioxidants that can keep eyes and joints healthy and protect humans against heart illnesses and cancer.
Apples that kill the desire(欲望) to eat could also be produced, with the first“extra-healthy’’apples on supermarket shelves within just four or five years.
The team that keeps studying apple DNA includes 100 scientists from five countries. Their research also suggests that around 65 million years ago, when dinosaurs began to die off the plant，which would finally become today’s apple tree, experienced a great genetic change. The number of many of its genes doubled. The extra genes allowed the apple to get used to worse conditions and go through a different development from peaches，strawberries and other related fruits.
【小题1】Why were fruit flies used for the research?

A．Apples produce chemicals that can change human genes.

B．Apples have antioxidants that kill chemicals that cause aging.

C．Apples are rich in vitamins that are needed in humans’bodies.

D．Apples produce chemicals that make apples taste more delicious.

On June 26, 2000, two scientists, called Francis Collins and Craig Venter, told the world that they could read the whole “map” of the human body: DNA. DNA is something that everybody has, and it tells the body what to do. DNA is the reason that we look like our mother and father, because we get some of their DNA to make our own.

People have been trying to understand the human body for a long time. In 1860, Gregor Mendel discovered a special reason why we look the same as other people in our family. It is because of small things named “genes” in our body. In 1953, James Watson and Francis Crick made another discovery and found out that those small parts are real messages written in the DNA with a special language.

In 1961, Marshall Nirenberg and Johann Matthaci found a message in DNA showing how DNA tells the cell（细胞）to build its parts. Scientists have now found all the words in the DNA map, but we still do not understand what they all do. By understanding what just one “word”   means, we can help save more people from several illnesses.

Most people hope that this will help make better medicine and help sick people. Other people worry that when people begin to know more words and find out lots of other information, we might use it in a wrong way, just to make people more attractive, or stop sick people from getting jobs. Man would have to meet a lot of trouble if DNA technic wasn’t limited（限制）in use.

1.When did we first know why we look like other people m our family?

A．In 1860           B．In 1953           C．In 1961           D．In 2000

2.What does the underlined word “ genes” mean?

A. The “map” of DNA.                B. A special language.

C. Small parts of DNA.                D. DNA

3.What did the two scientists first discover in 1961 ?

A. The “map” of DNA.               B. A new illness.

C. The language of DNA.              D. A message of DNA.

4.What can we do if we understand some “ words” of the language inside the body

A．Make people get new jobs.

B．Make medicine for illnesses.

C．Make maps of human.

D．Make people less attractive.

5.What do people think about this work’?

A．It can cause good or bad results.

B．It can cause only good results.

C．It can cause good results but won’t work.

D．It can cause only bad results.