Ever since humanity began to farm our own food, we've faced the unpredictable rain that is both friend and enemy. It comes and goes without much warning, and a field of leafy greens one year can dry up and blow away the next. Food security and fortunes depend on sufficient rain, and nowhere more so than in Africa, where 96% of farmland depends on rain instead of the irrigation common in more-developed places. It has consequences: South Africa's ongoing drought — the worst in three decades — will cost it at least a quarter of its corn harvest this year.
Biologist Jill Farrant of the University of Cap Town in South Africa says that nature has plenty of answers for people who want to grow crops in places with unpredictable rainfall. She is hard at work finding a way to take qualities from rare wild plants that are adapted to extreme dry weather and use them in food crops." The type of farming I am aiming for is literally so that people can survive as it's going to get drier and drier," Farrant says.
Extreme conditions produce extremely tough plants and a few fierce plants are highly adaptable to the everchanging conditions. Farrant calls one of them resurrection plants (复苏植物). During months without water under a harsh sun, they fade and contract until they look like a pile of dead green leaves but rainfall can revive them in the matter of hours. That is to say, when they detect and extend dry period, they produce sugars and certain stress-associated proteins and other materials in their tissues to enter a glass-like state that is “the most stable state that a plant can maintain”.
Last year, after Chinese team published a draft genome (基因组)of rock violet, one of the best studied resurrection plants, Farrant and colleagues published a detailed study of another candidate. One or both of these models will help researchers test their ideas-so far mostly done in the lab-on test plots.
1. Which can be responsible for the reduction in corn crop in South Africa?| A．Facing unpredictable rain. |
| B．Lacking advanced irrigation. |
| C．The food security. |
| D．The ongoing drought. |
| A．To maintain the most stable state of tough plants. |
| B．To grow crops in places with unpredictable rainfall. |
| C．To apply the special quality of wild plants to human farming. |
| D．To survive extreme dry weather and ever-changing conditions. |
| A．shrink | B．die | C．withdraw | D．rest |
| A．The research is still on trial. |
| B．Chinese team worked harder. |
| C．One of the candidates has been put into use. |
| D．The results contribute to resurrection plants. |
相似题推荐
【推荐1】The results from the world’s largest sleep study have shown that people who sleep on average between 7 to 8 hours per night perform better cognitively (认知地) than those who sleep less or more than this amount.
The world’s largest sleep study was launched in June 2018 and within days more than 40,000 people from the world participated in the online scientific investigation, which included an in-depth questionnaire and a series of cognitive performance activities.
“We really wanted to capture the sleeping habits of people around the entire globe. Obviously, there have been many smaller sleep studies of people in laboratories but we wanted to find out what sleep is like in the real world,” says Adrian Owen, western’s researcher in Cognitive Neuroscience and Imaging. “People who logged in gave us a lot of information about themselves. We had a fairly extensive questionnaire and they told us things like which medications they were on, where they were in the world and what kind of education they’d received because these are all factors that might have contributed to some of the results.”
More than half of all participants reported typically sleeping less than 6.3 hours per night, about an hour less than the study’s recommended amount. One shocking truth was that most participants who slept four hours or less performed as if they were almost nine years older.
Another surprising discovery was that sleep affected all adults equally. The amount of sleep associated with highly functional cognitive behavior was the same for everyone, regardless of age. Also, the harm associated with too little, or too much sleep did not depend on the age of the participants.
“We found that the best amount of sleep to keep your brain performing its best is 7 to 8 hours every night. We also found that people that slept more than that amount were equally harmed as those who slept too little,” says Conor Wild, Owen Lab Research Associate and the study’s lead author.
1. Where did the study take place?| A．In a lab. | B．In the street. |
| C．On TV. | D．On the Internet. |
| A．Career. | B．Diet. |
| C．Education. | D．Exercise. |
| A．Sleeping too much is as bad as sleeping too little. |
| B．People must sleep for eight hours every night. |
| C．Sleeping too little can make people look older. |
| D．People needn’t pay attention to the amount of sleep. |
| A．Owen and Wild are the first to study sleep. |
| B．Lack of enough sleep is a common problem. |
| C．All the people in the world show interest in the study. |
| D．There is no effective way to solve the sleep problem. |
【推荐2】THE WEEK, full of the world’s best news and facts, offering science, animals, puzzles, people, apps, photos, books, sports and eating insects, helps young people make sense of the world.
Iran Protests Continue To Escalate
People in Iran held more large protests against the government on October 30 after being warned not to by authorities. Students who took down partition walls meant to separate men and women in cafeterias were arrested. Protests began in September after the death of Mahsa Amini, who was arrested for showing her hair in public.
Lalitpur, Nepal Hindu Tihar Festival
People in Nepal marked the second day of the Tihar festival, which is dedicated to worshipping dogs and highlighting their loyalty to humans. The five-day festival is associated with the Hindu God Yama and each day is dedicated to a different animal. At the Sneha Care shelter, which is home to about 170 dogs, people spent the day giving dogs treats and placing orange garlands (花环) around their necks.
Singapore Green Tower Opens
A new 919-foot-tall skyscraper containing 80, 000 plants has opened in Singapore. The office building is also a “green oasis” for people to visit and explore. On the top floor there is a 4, 500-square foot roof top farm, which produces herbs, flowers, fruit, and vegetables for three restaurants in the building. It is estimated that the farm, which visitors can also walk through, grows between 154 and 220 pounds of produce each month.
1. Why did students pull down partition walls?| A．To warn the authorities. | B．To mourn the death of Mahsa Amini. |
| C．To separate men and women in cafeterias. | D．To fight against inequality of genders. |
| A．It is celebrated all around the world. |
| B．People have five days off to do the celebration. |
| C．Dogs are entertained for their loyalty on its second day. |
| D．Different animals are treated at the Sneha Care shelter. |
| A．A vertical farm. | B．An office building. |
| C．A shopping center. | D．An indoor entertainment center. |
Neophobia is common in children; it often happens at the dinner table. Some children just refuse to try new food because they don’t know what it will taste like, while others dislike new food before even smelling it. Some children take it to the extreme(极端) and will only eat a few foods that they like. Psychologist Dr. Elizabeth Capaldi says that, by the time children reach the age of two, they have formed their own eating habits that they don’t want to be disturbed by new offerings at the table.
A newly published study led by Dr. Lucy Cooke of University College London showed that picky eating in children results from genetic(遗传的) and environmental causes. The research, which followed the eating habits of 5,390 pairs of twins between the ages of 8 and 11, found that about 75% of the neophobia in the children was from their parents, while 25% was due to the influence of environment.
Children grow at a high speed during their first year, but that fast-paced growth tends to slow down by their second year. When children are not experiencing one of those fast growth periods, their body needs less energy; and that results in a smaller appetite(胃口). When children are not hungry, they tend to enjoy only food they like. They refuse new food and food that is not their favourite. Some children will limit the amount of food to only one kind, like hamburgers or pancakes, leaving all the other foods untouched.
In some cases, many real reasons why a child behaves as a picky eater exist. About 5% of children who are 10 years of age or younger have some type of neurological dysfunction(神经机能障碍) that influences their eating habits. These children may be easily hurt by some special smells, or their brain may not be able to process such sensory information properly.
1. The underlined word “Neophobia”in Paragraph 2 probably means_________.| A．the fear of something new or unknown |
| B．the worry about the amount of new food |
| C．the feeling of eating at the dinner table |
| D．the fear of eating tasty food |
| A．It paid more attention to the environmental effects on children’s eating habits. |
| B．It followed the eating habits of 5,390 children aged between 8 and 11. |
| C．It showed that genetics greatly affect children’s eating habits. |
| D．It suggested that parents should have good eating habits. |
| A．children’s growth speed stays the same in the first two years |
| B．children develop their own diet when they grow up |
| C．children tends to eat less when they grow up |
| D．children’s growth has an effect on their diet |
| A．exercise | B．sense | C．habit | D．Interest |
【推荐1】In times of intense stress, people sometimes let it out with a scream and a new study suggests that plants might do the same. Researchers at Tel Aviv University in Israel has found that plants let out ultrasonic (超声的) screams when damaged or stressed by drought.
The noises, falling within a range of 20 to 100 kilohertz, are too high-frequency for humans to hear, but other plants and some animals perceive them. Insects might be listening for sounds from stressed plants to assess their condition before laying eggs on their leaves. A moth (蛾) may decide against laying eggs on a plant that sounds water-stressed.
Researchers attached recording devices directly to plants to listen for secret sounds inside their stems (茎). In drought, air bubbles formed, burst and caused vibrations (振动) within the tissue that normally carries water up the plants’ stems. The process was picked up by the attached recording devices, but researchers wanted to know if any plant sounds could travel through the air.
So the team placed microphones 10 centimetres from stressed-out tomato and tobacco plants. They subjected one set of crops to drought and another to physical damage. A third group was untouched.
The microphones did pick up distinct sounds. On average, drought-stressed tomato plants let out about 35 ultrasonic screams per hour, while those with cut stems made about 25. Drought-stressed tobacco plants let out about 11 screams per hour, and cut crops made about 15 sounds in the same time. The average number of sounds from untouched plants fell below one per hour.
The researchers also attempted to identify each plant group just based on its screams. Using a type of artificial intelligence calculations, the team picked out distinct features in each set of sounds and successfully sorted their plants into three kinds: “dry, cut or untouched.”
If it is not too costly to set up the recording in a field situation, farmers might be able to hear these stress signals too. In future, enabling farmers to listen for water-stressed plants could “open a new direction”, which will be increasingly important as climate change exposes more areas to drought.
1. The moth is mentioned in paragraph 2 to show __________.| A．moths need enough water when laying eggs |
| B．some animals are able to hear plants scream |
| C．some insects are picky about their surroundings |
| D．wildlife species depend on each other when stressed |
| A．Plants’ sounds couldn’t be detected by humans. |
| B．Plants can be grouped according to their features. |
| C．Plants’ screams are related to stress types in a way. |
| D．Air bubbles contribute to the lack of water in plants. |
| A．Supporting evidence for the research result. |
| B．Potential application of the research findings. |
| C．A further explanation of the research methods. |
| D．A reasonable doubt about the research process. |
| A．Plants’ Vibrations: Way to React to Stress |
| B．Stress Signals: Secret Newly Found in Plants |
| C．Green Screams: Plants Make Noises When Stressed |
| D．Ultrasonic Screams: Discovery Opens a New Chapter |
【推荐2】The rapid pace of global warming and its effects on habitats raise the question of whether species are able to keep up so that they remain in suitable living conditions. Some animals can move fast to adjust to a quickly changing climate. Plants, being less mobile, rely on means such as seed dispersal (传播) by animals, wind or water to move to new areas, but this redistribution typically occurs within one kilometer of the original plant. Writing in Nature, Juan P. González-Varo sheds light on the potential capacity of migratory birds to aid seed dispersal.
González-Varo and colleagues report how plants might be able to keep pace with rapid climate change through the help of migrating birds. They analyzed an impressive data set of 949 different seed-dispersal interactions between bird and plant communities, together with data on entire fruiting times and migratory patterns of birds across Europe.
Perhaps the most striking feature of these inferred seed movements is the observation that 35 percent of plant species across European communities, which are closely related on the phylogenetic tree (进化树谱), might benefit from long-distance dispersal by the northward journey of migratory birds. This particular group of plants tends to fruit over a long period of time, or has fruits that persist over the winter. This means that the ability of plants to keep up with climate change could be shaped by their evolutionary history – implying that future plant communities in the Northern Hemisphere will probably come from plant species that are phylogenetically closely related and that have migrated from the south.
This study provides a great example of how migratory birds might assist plant redistribution to new locations that would normally be difficult for them to reach on their own, and which might offer a suitable climate.
1. What can we learn from the first paragraph?| A．Plants can better adapt to global warming than animals. |
| B．Quickly changing climate doesn’t have great effects on animals. |
| C．Some animals and plants move to continue their species ‘ survival. |
| D．Wind and water contribute to plants' long-distance redistribution. |
| A．By studying related data. | B．By doing comprehensive surveys. |
| C．By interviewing plant experts. | D．By conducting field research . |
| A．The majority of plant species benefit a lot from long-distance dispersal. |
| B．Plants with longer fruiting times adapt better when they are transported farther. |
| C．Plants have a better chance of survival if their seeds are dispersed across Europe. |
| D．Plant communities in different hemispheres will be phylogenetically less related. |
| A．Ways to Redistribute Plants to New Climates |
| B．Impacts of Climate Change on Migratory Birds |
| C．Migratory Birds Aid the Redistribution of Plants |
| D．Plants Struggle to Keep Pace with Climate Change |
【推荐3】Are you wondering whether it’s worth going for a little jog? Don’t hesitate, and get your sports shoes on. A new study shows that proper running lowers the risk of premature (过早的) death.
In an analysis of 14 previous studies from the US and Denmark, the group of researchers from institutes in Australia and Finland concluded that increasing running participation would probably lead to substantial improvements in population health and longevity. The studies involved 232,149 participants over time periods ranging from 5.5 to 35 years.
Overall, people running any distance were associated with a 27% lower risk of death from all causes than those who did not, the analysis shows. Running was also associated with a 30% and 23% lower risk of death from cardiovascular (心血管的) disease and cancer, respectively.
Previous studies had concluded “inconsistent findings” about whether running could lower the risk of premature death, according to the researchers. Lead researcher Jim White, a professor at Victoria University in Melbourne, told CNN, “Our recent findings may motivate physically inactive individuals to take up running and those who already run to keep on doing it.”
He added that doctors may be encouraged by our findings to promote running as a part of “lifestyle medicine”. In their paper, which will be published in the British Journal of Sports Medicine, the researchers say health professionals are sometimes wary of promoting running because vigorous (剧烈的) use of it has been linked with sudden cardiac death.
Jim and his team countered this by noting that the benefit of running outweighs the risk. However, they did say advice should be given on a case-by-case basis, as running might not be appropriate for everyone. Although running has a clear overall health benefit, the researchers point out that higher “doses” of running may not reduce the risk of premature death further. According to the WHO’s guidelines, adults aged between 18 and 64 should take 150 minutes of gentle exercise or 75 minutes of vigorous exercise each week.
1. What did the new study focus on?| A．The benefit of jog. | B．People’s lifestyles. |
| C．People’s living conditions. | D．The popularity of jog. |
| A．Researchers’ promotion of sport. |
| B．People’s involvement in running. |
| C．Doctors’ quicker treatment. |
| D．People’s losing weight. |
| A．Certain. | B．Capable. |
| C．Confident. | D．Cautious. |
| A．The risk of exercising vigorously. |
| B．The suggestion on running appropriately. |
| C．The reason why people should keep running. |
| D．The argument about whether running benefits people. |
【推荐1】Plants don’t have ears or a central nervous system, but new research out of the University of Missouri has demonstrated that they might still have the ability to “hear”. More specifically, plants have been shown to exhibit an immune (免疫) response to the mere sound of a hungry insect.
For the study, researchers played the sound of a caterpillar chewing to a group of plants, which caused slight vibrations (振动) on the plants’ leaves. The plants were able to recognize these vibration patterns as danger, and responded by mounting the appropriate immune response. In other words, it appears that plants can “hear” themselves being chewed on.
Researchers assume that plants achieve this remarkable ability thanks to proteins that respond to pressure found within their cell membranes. Vibrations cause pressure changes within the cell, which can change the behavior of the proteins; however, additional study will be required to confirm or deny this theory.
Once researchers identify the exact mechanisms at play in this process, it could lead to advances in crop protection. Farmers could potentially learn to use sound to cause a plant’s natural chemical defenses against insect threats, rather than turning to poisonous chemicals.
“We can imagine applications of this where plants could be treated with sound or genetically engineered to respond to certain sounds that would be useful for agriculture,” said study author Heidi Appel.
The study adds to the growing list of ways that plants have been shown to sense their environments. They are not the boring organisms that many people assume they are. For instance, some plants are able to communicate with each other and signal upcoming danger to their neighbors by releasing chemicals into the air. Plants can respond to light (think about sunflowers) and temperature. Some can even respond to touch, such as the Venus flytrap (捕蝇草), which snaps shut when an insect stimulates its hairs.
1. Why did researchers carry out the study?| A．To find out if plants can react to sounds. |
| B．To learn how plants recognize dangers. |
| C．To discover if plants can shake their leaves. |
| D．To see how plants improve immune systems. |
| A．To remove insects. | B．To protect crops. |
| C．To treat plant diseases. | D．To produce chemicals. |
| A．There are more plants than we know. |
| B．Plants are more active than we think. |
| C．Plants fit in well with their environments. |
| D．Lots of secrets about plants remain unclear. |
| A．Can plants “talk” with each other? |
| B．How do plants make use of sounds? |
| C．Can plants “hear” themselves being eaten? |
| D．How do plants defend themselves against attacks? |
【推荐2】Readers can explore the wonders of nature with Big Tree. The book was written by famous author and illustrator (插画家) Brian Selznick. It is filled with detailed black-and-white illustrations, which took years to complete.
The story introduces Merwin and Louise, two tiny Sycamore seeds (梧桐树种子) who began life during the time when dinosaurs (恐龙) travelled around the Earth. After they fell from their mother tree, they started a dangerous 147-million-year adventure to the modern day.
After reading it, I met with the famous author and illustrator at his home in La Jolla, California. Selznick explained the lessons that nature offers about helping our planet and each other. “All of us can do something to help the real seed,” Selznick said. “No matter how small you feel, there’s always something you can do.”
As for his main goal when writing Big Tree, Selznick said, “Readers feel like they are learning about interesting stories when they read Big Tree, but actually and secretly, they are learning about real science. That’s why I wrote Big Tree.”
In order to write Big Tree, Selznick went to the New York Botanical Garden, where he talked to a wonderful park manager. She walked him through the forest and talked about the way leaves work, the way trees grow and the way trees experience time.
Selznick said he learned a lot while creating Big Tree. “The manager thinks that forests are really communities. It really surprised me,” he said. “We live in communities, and when we run into trouble or danger, we communicate with each other to find solutions. Trees are doing the same thing. We’re all part of a community. And that, to me, was a really important part of Big Tree.”
1. What does paragraph 2 mainly focus on?| A．The main idea of Big Tree. | B．The discussion about Big Tree. |
| C．The review of Big Tree. | D．The story behind Big Tree. |
| A．To show the illustration art. | B．To share an interesting story. |
| C．To encourage readers to learn. | D．To make real science interesting. |
| A．He did some research. | B．He planted some trees. |
| C．He asked others’ advice. | D．He stayed in the forest alone. |
| A．Trees are important for communities. | B．Trees can communicate with each other. |
| C．Trees can protect people against danger. | D．Trees run into trouble more often. |
【推荐3】The earliest tomatoes were little sour berries. They grew among low bushes in dry, sunny places in the Andes Mountains in South America. It was about 350 million years ago.
Tomato plants are relative to nightshade (茄属植物), which has poison. The leaves and stems of tomato plants have poison , but the berries are good to eat. The berries are red so that animals can find them easily and eat them. The animals carry the seeds to other places. That was how earliest tomato plants found new places to grow. Tomatoes are also relative to tobacco, chili peppers and potatoes.
When people first came to South America about 20,000 years ago, they ate these tiny wild tomatoes. Travelers brought a few kinds of wild tomato plants from the Andes to Central America, there the ancestors of the Maya began to farm them. Nobody knows exactly when people began farming tomatoes, but it probably was much later than corn and beans, and it was surely before 500 BC. These Central American fanners bred tomatoes to be bigger and sweeter than the wild ones.
By the time Spanish explorers got to Tenochtitlan in Mexico in 1521 AD, the Aztec people ere eating a lot of tomatoes, made a sauce of chopped (剁碎的)tomatoes, onions, salt and chili peppers that was a lot like our salsa. The word “tomato” comes from their Nahuatl word “tomato”.
Because tomatoes weren't farmed until pretty late, farmers further north had not yet been able to adapt heir growing season to working in North America. Even today, it's pretty hard to get your tomatoes ripe in the northern parts of North America before the growing season ends.
1. What do we know about the earliest tomatoes?| A．They were big sweet berries. |
| B．They grew in Central America. |
| C．They grew in dry, sunny places. |
| D．They grew about 35 million years ago. |
| A．People grew them in new places. |
| B．They grew in new places naturally. |
| C．Their seeds were carried away by wind. |
| D．Their seeds were carried away by animals. |
| A．The farmers sold them to others. |
| B．The farmers disliked their taste. |
| C．The farmers tried to improve them. |
| D．The farmers showed no interest in them. |
| A．How to grow tomatoes. |
| B．The history of tomatoes. |
| C．When to grow tomatoes. |
| D．The places where tomatoes grow. |
