Smoking is harmful. But as soon as you quit the habit, everything will be OK, right?
Wrong.
New research has found that even if you give up smoking, the damage it has done to your genes (基因) will stay there for a much longer time.In the research, a team of US scientists studied the blood of 16,000 people. Among them, some were smokers, some used to smoke, and the rest were non-smokers. Scientists compared their genes and found that more than 7,000 genes of smokers had changed--a number that is one-third of known human genes.
According to NBC News, both heart disease and cancer are caused by genetic changes. Some people may have had the changes when they were born, but most people get them in their day-to-day lives while doing things like smoking.
When you stop smoking, a lot of these genes will return to normal within five years.
This means your body is trying to heal (治愈) itself of the harmful effects of smoking. But the changes in some of the genes stay for longer. They can stay for as long as 30 years, It’s almost like leaving a footprint on wet cement (水泥)----it will always be there, even when you’ve walked away and when the cement becomes dry.
Although the study results may make people unhappy, there is a bright side: the findings could help scientists invent medicine to treat genetic damage caused by smoking or find ways to tell which people have heart disease or cancer risks.
1. The function of Paragraph 1 is to_________ .
A. introduce the topic of the passage B. give an example
C. make an argument D. show the main idea of the passage
2. Most genetic changes happen because of___________ .
A. people’s condition at birth B. environmental pollution
C. people’s bad living habit D. heart disease and cancer
3. The underlined word “it” in Paragraph 6 refers to__________ .
A. the footprint B. the cement...
C. the harmful effect D. the genetic change
4. Which of the following statements is true?
A. The findings are the fruit of more than three years’ research.
B. The findings have prevented more people from starting smoking
C. The findings offer evidence that a damaged gene can heal itself.
D. The findings help to find cures for genetic damage caused by smoking.
ACAD
A. Profits enlarging B. Technology developing C. Education investing D. Benefits transferring E. Dominance disappearing F. A nation rising |
The following is an imaginary diary entry written by US president. This diary is part of Global Trends 2025, which was written by the US National Intelligence Council
80
The
81
The
82
Global wealth and economic power will shift from West to East.
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The transition from old fuels to new will be slow, as will the development of new technologies that present feasible alternatives to fossil fuels or help eliminate food and water problems. All current technologies are inadequate, and new ones will probably not be commercially possible by 2025