出自:2023年初级学期期末统一考试英语机考
Do you prefer coffee or tea?The answer to that question might in part be down to your genes, research suggests. Scientists say a genetic predisposition to perceiving the bitterness of particular substances appears to nudge us towards one beverage or the other. The study, published in the Scientific Reports journal, involved two sets of data. The ?rst was a large twin study which showed that, at least in those of European ancestry, particular genetic variants are linked to the strength of perception of different tastes: one speci?c variant was associated with slightly higher ratings of bitterness for caffeine, another to greater bitterness for quinine and a third to greater bitterness for a drug known as propylthiouracil, or prop. The team found people with a greater genetic predisposition to perceiving the bitterness of caffeine drank a little more coffee, but an increased perception of the bitterness of quinine and prop were linked to a small reduction in coffee drinking. “While the effect of perception on your daily coffee intake might be relatively small—only a 0.15 cup per day increase—from a normal caffeine taster to a strong caffeine taster, it actually makes you 20% more likely to become a heavy drinker— drinking more than four cups per day,” said Jue Sheng Ong, ?rst author of the research from QIMR Berghofer Medical Research Institute in Australia. “Our taste genes partially play a role in how much coffee, tea or alcohol we drink,” he said. “The preference towards tea can be seen as a consequence of abstaining from coffee, because our genes might have made coffee a little too bitter for our palates to handle.”
1-1、According to this passage, the answer to the question “Do you prefer coffee or tea? ” might in part be down to your genes.
A、√
B、×
WHY BUILD A SPACE ELEVATOR? The space elevator will reduce the cost of getting from Earth to space. It will also allow us to take very large payloads into space very easily, very safely. Because of that, we can build cities on the moon. We can build space stations. We can build large solar arrays in space to collect energy from the sun and beam it down to Earth. WHY NOT JUST USE ROCKETS INSTEAD? Rockets are very expensive. The shuttle costs $10,000 a pound to put a payload into low-Earth orbit, and if you want to go to the moon or Mars, it.s hundreds of thousands of dollars per pound or more. Rockets are also very limited in the amount of payload they can carry, and they.re risky. With a space elevator, the cost is a fraction of that—it may go down to 100th or 1,000th of current costs—and there are no rocket engines that might explode. WHAT WOULD IT BE LIKE TO RIDE THE ELEVATOR? You.d go to an ocean platform, you.d climb into a module, and you.d feel it start moving. You.d see the Earth fall away. In just a half hour or so, you.d pass up through the clouds, and you.d start to see the curve of the horizon. Another half an hour to an hour later, you.d basically be in space. You.d see stars, even in the middle of the day. Eventually you.d be weightless. It.d be a very smooth ride; there wouldn.t be any shaking. ARE THERE POTENTIAL DRAWBACKS TO OPENING SPACE THIS WAY? Everything we do has the potential for creating some bad. If we mine an asteroid, the asteroid.s going to look ugly, just like a mine here. But I think the benefits of opening up space far outweigh the damage that we can see—benefits in terms of gaining energy from space to replace oil, additional capabilities in telecommunications, manufacturing in space, additional real estate and exploration.
1-1、If a space elevator is built, what can’t be built by us?
A、Cities on the moon.
B、Space stations.
C、Skyscrapers in space.
D、Expressways in space.
By 2050, the world.s population is projected to rise to 9 billion from just over 7 billion currently. Proponents of genetically modified foods say they are safe and can boost harvests even in bad conditions by protecting against pests, weeds and drought. This, they argue, will be essential to meeting the needs of a booming population in decades to come and avoiding starvation. However, Doug Gurian-Sherman, senior scientist for the food and environment program at the Union of Concerned Scientists, an advocacy group, said genetic engineering for insect resistance has provided only a modest increase in yields since the 1990s and drought-resistant strains have only modestly reduced losses from drought. Moreover, he said conventional crossbreeding or cross-pollinating of different varieties for desirable traits, along with improved farming, is getting better results, boosting yields at a lower cost. In fact, much of the food Americans eat has been genetically modified by those conventional methods over thousands of years, before genetic engineering came into practice. “Overall, genetic engineering does not get nearly the bang for the buck as conventional breeding and improve agricultural practices,” Gurian-Sherman said. His organization advises caution on GM foods and favors labeling, though it acknowledges the risks of genetic engineering have sometimes been exaggerated. Andrea Roberto Sonnino, chief of research at the U.N. food agency, said total food production at present is enough to feed the entire global population. The problem is uneven distribution, leaving 870 million suffering from hunger. He said world food production will need to increase by 60 percent to meet the demands of 9 billion by 2050. This must be achieved by increasing yields, he added, because there is little room to expand cultivated land used for agriculture. Genetically modified foods, in some instances, can help if the individual product has been assessed as safe, he said. “It.s an opportunity that we cannot just miss.”
1-1、Para. 1 mentions that the risks of genetic engineering are not that horrible.
A、√
B、×