1 . It has always been assumed that noise is a problem unique to animals. But a new study by Dr. Ravandi, a botanist at Shahid Beheshti University in Tehran, has revealed that plants suffer too.
That plants can be affected indirectly by noise pollution has never been in doubt. What has remained unknown is whether or not plants themselves suffer directly from noise pollution.
Sounds are pressure waves transmitted (传播) through gases, liquids and solids. Scientists have previously assumed plants may be able to sense these waves as they are struck by them. A number of experiments have confirmed this in recent years — plants exposed to ultrasound in the lab have shown a range of negative responses including the expression of stress-related genes, slow growth and reduced seed development.
Yet exposing plants to ultrasound is not the same as growing them in the presence of actual traffic noise. To this end, Dr. Ravandi decided to set up an experiment to explore it.
Working with a team, Dr. Ravandi grew two species in his lab that are commonly found in urban environments — marigolds and sage. The plants, grown from seed and allowed to mature for two months in the same space, were divided into two groups. One group was exposed to 73 decibels (分贝) of traffic noise recorded from a busy motorway in Tehran for 16 hours a day. The other group was left to grow in silence. After 15 days had passed, samples were taken from the youngest fully expanded leaves on every plant in the experiment and studied.
None of the plants exposed to the traffic noise did well. Analysis of their leaves revealed all of them were suffering. Chemical compounds (化合物), such as hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) , are indicators of stress in plants and both were found at much higher levels in the plants exposed to the traffic noise. Most notably, malondialdehyde (MDA) levels in the sage plants exposed to noise were double what they were in those grown in silence and hydrogen peroxide (H₂O₂) levels were three times higher in marigolds grown with the noise than those grown in silence.
Dr. Ravandi’s findings make it clear that, though plants lack ears, the vibrations (震动) generated by the noise of traffic still bother them enough to give rise to dramatic stress responses that are not much different to those that would be found in plants exposed to drought, highly concentrated salt or heavy metals in their soil.
The question now arises whether all species are affected similarly by noise pollution. Nature is not silent. It remains a mystery if certain plant species have developed mechanisms to address noise pollution, which could potentially be transferred to urban plants in the future.
1. What did the new study focus on?| A．Plants’ exposure to ultrasound. |
| B．Plants’ sensitivity to pressure waves. |
| C．The direct impact of noise pollution on plants. |
| D．The seed development of plants grown with noise. |
| A．The facilities of the experiment. | B．The analyses of the experiment. |
| C．The process of the experiment. | D．The background of the experiment. |
| A．Noise pollution had a little impact on plant leaves. |
| B．Noise-exposed plants showed certain levels of stress. |
| C．MDA levels in sage plants grown in silence were higher. |
| D．Traffic noise caused rapid pressure responses in all plants. |
| A．Building barriers to protect plants from traffic pollution. |
| B．Studying the relationship between soil quality and plant health. |
| C．Exploring strategies to preserve plant ecosystems in rural areas. |
| D．Developing noise-resistant plant species for an urban environment. |
1. What does Lily suggest Mr. Stenson doing?
| A．Using the pesticide. | B．Changing the crop. | C．Watering the fields. |
| A．He often shares his products. |
| B．He lives far from Lily. |
| C．He is good at farming. |
3 . Coffee is probably the world’s least expensive success power tool. Coffee builds better teams and increases your leadership ability. Coffee also increases your immunity. Unfortunately, we may not be enjoying the benefits or pleasures of coffee too much longer. According to ecologists, there’s a good chance that in 20 or 30 years, the varieties of coffee that we drink today will be extinct (灭绝的). And we’ll be drinking a coffee substitute that more or less resembles the drink we enjoy today.
The problem, of course, is the pace of climate change. Successful coffee cultivation has three preconditions: a warm, highly stable (稳定的) tropical (热带的) climate with altitudes that keep air temperature between 18 and 20 degrees Celsius, rich soil full of natural nutrients, and an ecological environment that’s pest and disease resistant.
Coffee is a crop that is only grown in a thin band called the “coffee belt” close to the equator (赤道). It simply won’t grow anywhere else. Unfortunately, the “coffee belt” is extremely vulnerable to climate change. If the air is too cold or too hot, it prevents the growth of the coffee plant. Climate change also creates environmental stress, which spreads parasites, pests and plant diseases. All of these increase the fragility of the coffee crop and create the possibility of species-destroying rot.
Unfortunately, almost all of these species exist only in Ethiopia, a country that climate change is already hammering. As the environmental nonprofit USAID points out: “Ethiopia is one of the world’s most drought-prone countries. The country is faced with numerous development challenges that exacerbate its weakness facing climate change including increases in temperature, unstable rainfall and unpredictability of seasonal rain, and increased incidences of drought and other extreme events.”
In other words, even as climate change threatens coffee as it exists today, climate change is also eating away at the root source which we might turn to for replacement species.
What to do? Well, take the time to savor each cup of coffee you drink. Beyond that, stop electing the politicians who deny climate change.
1. What is the author’s feeling about the future of coffee?| A．Helpless. | B．Bored. | C．Happy. | D．Concerned. |
| A．A tropical climate. | B．The rich soil. |
| C．The increasing temperature. | D．The stable rainfall. |
| A．remove | B．worsen | C．decrease | D．accept |
| A．Changing Climate for Coffee | B．Enjoy Coffee While You Can |
| C．Benefits from Coffee Drinking | D．Conditions for Coffee Planting |
1. How many people died in a landslide in 2003?
| A．About two hundred. | B．Over one thousand. | C．About two thousand. |
| A．Growing grass. | B．Cutting down trees. | C．Growing population. |
| A．Growing more forests. |
| B．Chopping down the old forests. |
| C．Getting busy in protecting our country. |
| A．Clothes. | B．A plant. | C．A season. |
1. How does the woman feel at first?
| A．Curious. | B．Surprised. | C．Excited. |
| A．Flowers. | B．Mushrooms. | C．Trees. |
| A．Two. | B．Three. | C．Four. |
| A．On Thursday. | B．On Friday. | C．On Saturday. |
7 . Scientists have been experimenting with playing sounds to plants since at least the 1960s, during which time they have been exposed to everything from Beethoven to Michael Jackson. Over the years, evidence that this sort of thing can have an effect has been growing. One paper, published in 2018, claimed that an Asian shrub known as the telegraph plant grew substantially larger leaves when exposed to 56 days of Buddhist music — but not if it was exposed to Western pop music or silence. Another, published last year, found that marigolds and sage plants exposed to the noise of traffic from a busy motorway suffered growth difficulty.
Plants have been evolving (进化) alongside the insects that eat them for hundreds of millions of years. With that in mind, Heidi Appel, a botanist now at the University of Houston, and Reginald Cocroft, a biologist at the University of Missouri, wondered if plants might be sensitive to the sounds made by the animals with which they most often interact. They recorded the vibrations made by certain species of caterpillars (毛毛虫) as they chewed on leaves. These vibrations are not powerful enough to produce sound waves in the air. But they are able to travel across leaves and branches, and even to neighbouring plants if their leaves touch.
They then exposed tobacco plant — the plant biologist’s version of the laboratory mouse — to the recorded vibrations while no caterpillars were actually present. Later, they put real caterpillars on the plants to see if exposure had led them to prepare for an insect attack. The results were striking. Leaves that had been exposed had significantly higher levels of defensive chemicals, making them much harder for the caterpillars to eat. Leaves that had not been exposed to vibrations showed no such response. Other sorts of vibration — caused by the wind, for instance, or other insects that do not eat leaves — had no effect.
“Now speakers with the right audio files are more often being used to warn crops to act when insects are detected but not yet widespread,” says Dr. Cocroft. “Unlike chemical pesticides, sound waves leave no dangerous chemicals.”
1. What can we learn about plants from the first paragraph?| A．They may enjoy Western music. | B．They can’t stand Buddhist music. |
| C．They can react to different sounds. | D．They can make different sounds. |
| A．Plants can make a cry for help. | B．Plants evolve alongside insects. |
| C．Plants are sensitive to the sounds. | D．Plants have been studied for years. |
| A．They can recongnize harmful vibrations. | B．They look like laboratory mice. |
| C．They can threaten the caterpillars. | D．They can release poisonous chemicals. |
| A．Disadvantages of chemical pesticides. | B．Application of the experimental results. |
| C．Interaction between plants and insects. | D．Warning system of widespread insects. |
1. Why is the baobab tree thought to be strange-looking?
| A．Its trunk sometimes measures more than ten metres in diameter. |
| B．Its trunk is thicker at the top than at the bottom. |
| C．Its branches near the top are longer than those near the ground. |
| A．Its leaves. | B．Its trunk. | C．Its skin of the tree. |
| A．Its empty trunk can be used by people to build everything. |
| B．Its flowers can turn into a kind of cucumber. |
| C．Its leaves and branches can keep the rain water cool and clean. |
| A．The baobab — unusual but useful |
| B．The baobab — a tree that people can make good use of |
| C．The baobab — a strange tree that can make ropes |
When John pulled into his mother’s driveway with his young daughter, Lily, the sight of the familiar lychee (荔枝) tree welcomed them. “Look, Lily,” John said, pointing to the towering tree in the front yard. “It’s the family tree.”
Lily smiled as John treated the tree as if it were a real family member, patting its trunk (树干) affectionately. As they were admiring the tree, the screen door opened and out stepped Grandma Mei, bathed in the warm Florida sunlight. Grandma Mei, who came from the province of Guangdong in China, was known for her green thumb, particularly when it came to lychees.
Seeing her granddaughter, Grandma Mei adjusted her baseball cap and asked if Lily was ready for some lychees. But Lily hesitated, for the fruit’s appearance was unlike any other fruit she had tried before. With a laugh, Grandma Mei gave her a gentle hug. “More lychees for me then, John,” Grandma Mei said.
“Let’s get busy!” John said with enthusiasm, rubbing his hands together. “Family tree’s waiting.”
Hearing Dad calling the tree by name, Lily couldn’t help laughing. “Laugh if you want, Lily, but this tree is really family. On cold nights, before family tree was fully grown, Grandma Mei used to take my blanket and throw it over that tree.” Grandma Mei nodded, adding that she had to protect the tree from bad weather so that it would become a big strong tree and grow fruit for the whole family.
John, eager to start the day’s work, began climbing the tree, determined to harvest the best lychees for the family. Lily watched in amazement, noticing the clusters (簇) of lychees, their skin rough yet inviting.
As John skillfully cut through the branches with a cutter, Lily expressed her concern for the well-being of the tree. John explained to her that cutting the ends of branches won’t hurt family tree. Instead such behaviour made it healthier and stronger.
注意：
1.续写词数应为150左右；
2.请按如下格式在答题卡的相应位置作答。
Lily’s hesitation towards the fruit gradually shifted to curiosity and she wanted to try it.
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Later in the afternoon, they all sat under the tree, surrounded by boxes filled with lychees and sharing stories related to lychees.
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10 . Scientists have shown how plants can protect themselves against genetic (基因的) damage caused by environmental stresses. The growing tips of plant roots and shoots have an in-built mechanism (机制) that spells cell death if DNA damage is detected, avoiding passing on faulty DNA.
Plants have small populations of stem cells (干细胞) at the tips of their roots and shoots, which enable them to continuously grow and produce new tissues throughout their lifetime. These stem cells serve as ancestors for plant tissues and organs. However, any genetic faults present in the stem cells will continue to exist and be passed on permanently throughout the plant’s life, which could last thousands of years.
Given the critical role of stem cells and their exposure to potentially dangerous environments at the growing tips of roots and shoots, safeguards are necessary to prevent stem cell faults from becoming fixed. Researchers Nick Fulcher and Robert Sablowski, funded by the Biotechnology and Biological Sciences Research Council, aimed to uncover these protective mechanisms. Through experiments involving X-rays and chemicals, they discovered that stem cells were more sensitive to DNA damage compared to other cells.
When DNA damage occurs, the cells have the capacity to detect it and cause programmed cells to die, preventing the propagation of the damaged genetic code to the rest of the plant tissues. This process has similarities to the safeguard mechanism found in animal cells, which has been broadly studied due to its relevance in preventing cancer.
The identification of a similar protective system in plants is of great interest in the field of plant development. It also helps scientists develop plants that can better handle environmental stress. So knowledge of how plants deal with these stresses is of fundamental significance to agricultural science’s response to climate change.
1. What is the function of the in-built mechanism in plants?| A．To produce more roots and shoots. | B．To increase the overall lifetime of the plant. |
| C．To enhance plant growth and nutrient intake. | D．To stop genetic faults in stem cells passing on. |
| A．They are relatively abundant in quantity. | B．They are resistant to environmental stresses. |
| C．They make quick response to DNA damage. | D．They have the ability to repair damaged DNA. |
| A．Spread. | B．Change. | C．Existence. | D．Self-repair. |
| A．The way of dealing with climate change on the earth. |
| B．The significance of identifying the protective system in plants. |
| C．The method of ensuring plant survival under environmental stress. |
| D．The urgency of developing plants that can handle environmental stress. |
