题目内容
The genes of the cloned animals are so arranged that it can't________ such a disease, so it soon died.
A. overlook B. resist C. exist D. withdraw
B
om depression often have problems sleeping, getting up on time, and doing work productively.What does fizz (气泡) taste like? In Bubbly (多泡的)drinks such 
as sodas, tiny bubbles give the drink a lift--- and have a distinct taste, In a new study on mice, scientists have connected that fizzy-taste feeling to the ability to taste sourness, such as that of oranges or vinegar.
Scientists first thought the taste of bubbles came from the bubbles bursting on the tongue, but now ate starting to think differently. Charles Zuker, of Columbia University, and his team studied the nervous system of mice to understand how the tongue tastes carbon dioxide, which is the gas that makes up the bubbles.
Animals, including human beings, are able to detect different tastes by using taste buds(味蕾) which pick up tastes in the mouth, and then send them to the brain. In the experiment, different groups of mice were genetically engineered to be missing one of the senses involved in taste. “Genetically engineered” means the researchers were able to turn off the switches for certain senses by changing the genes responsible for taste. The mice in one group could not taste sweet; another, sour; the third, bitter, and the fourth, salt. When the scientists gave carbon dioxide to the mice, the nervous systems of all the mice responded to the gas, except those of the mice that could not taste sour.
This shows that the taste of the bubbles must be sour, and that by turning off the ability of the mice to taste sour, the scientists also turned off their ability to taste carbon dioxide. When they studied the cells that detect sourness, the researchers found a protein attached to the cells that is important to the process of tasting carbon dioxide. When carbon dioxide comes into contact with this protein, the protein knocks off particles called protons. These protons(质子), in turn, travel to the brain, which says ,” Hey! That’s a taste!”
It may seem like a lot of work to get from a can of soda to a taste, but the science of the senses is anything but simple, “ Taste is a challenging system to study,” one researcher says.
【小题1】 What is the most important function of the bubbles?
| A．To look interesting . | B．To make drinks taste good. |
| C．To make drinks funny. | D．To produce a lot of fizz. |
| A．sourness has nothing to do with the taste of bubbles. |
| B．there is a connection between sourness and bubbles. |
| C．the taste of bubbles is better if it’s less sour. |
| D．most mice cannot taste carbon dioxide. |
| A．the taste of bubbles is produced by the bubbles bursting on the tongue. |
| B．the nervous systems of mice show how the tongue tastes carbon dioxide. |
| C．taste seems simple but is very complex to research. |
| D．nerve cells sending signals to the brain is the first step in tasting something. |
| A．Nervous Systems Understand How the Tongue Tastes. |
| B．The Process of Taste |
C．The taste of Bubbles. |
| D．Different Animals Detect Different Tastes. |
Good Genes Mean Long Life
Scientists have discovered that living to the age of 100 may have nothing to do with the lifestyle you lead and everything to do with the type of genes you have.
For the lucky carriers of “Methuselah” genes, worries over smoking, eating unhealthily and not getting enough exercise may not be as necessary as to those of us without the special gene pattern (组合).
The “Methuselah” genes could give extra protection against the diseases of old age such as cancer and heart disease. They could also protect people against the effects of the unhealthy lifestyles that we believe will lead us to an early death, scientists say. However, the genes are very rare.
The genes include ADIPOQ, which is found in about 10 percent of young people but in nearly 30 percent of people living past 100. They also include the CETP and the ApoC3 genes, which are found in 10 percent of young people, but in about 20 percent of people over 100 years old.
Some of those genes were discovered by a research group at the Albert Einstein College of Medicine in New York, led by Professor Nir Barzilai. The team studied the genes of over 500 people over 100 years old, and their children.
The studies show that tiny mutations (变异) in the make-up of some genes can greatly increase a person’s lifespan (寿命). Barzilai told a Royal Society conference that the discovery of such genes gave scientists clear targets for developing drugs that could prevent age-related diseases, allow people to live longer and stay healthy.
David Gems, a researcher at University College London, believes that drugs to slow ageing will become widespread.
“If we know which genes control longevity (长寿) then we can … target them with drugs. That makes it possible to slow down ageing,” he told The Times.
“Much of the pain and suffering in the world are caused by ageing. If we can find a way to reduce that, then we are obliged (义不容辞的) to take it.”
1.According to the article, which of the following is the most important if a person is to live to the age of 100?
|
A．Eating healthy food every day. |
B．Having the right types of genes. |
|
C．Having a healthy lifestyle. |
D．Taking drugs that prevent ageing. |
2.According to the article, the ApoC3 gene is found in ________ of people over 100 years old.
|
A．10% |
B．20% |
C．30% |
D．50% |
3.Which of the following statements is TRUE of the research led by Professor Nir Barzilai?
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A．The team studied the genes of over 100 people over 100 years of age. |
|
B．The researchers found that mutations in certain genes lead to longer life. |
|
C．The researchers found ways to develop drugs that could cure age-related diseases. |
|
D．The study suggested that most people have genes that could lengthen their lives. |
4. According to David Gems, ________.
|
A．drugs to slow ageing will be very expensive |
|
B．modern science will be able to find more longevity genes |
|
C．it is the duty of medical scientists to fight the problems of ageing |
|
D．scientists can make new genes that will allow longer life |