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. |
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. |
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. |
4 . 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. |
5 . 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. |
6 . Plants do not suffer in silence when thirsty or stressed, according to a new study published today in Cell.
Plants that need water or have recently had their branches cut produce up to roughly 35 sounds per hour, the authors found. But well-watered and uncut plants are much quieter, making only about one sound per hour.
The reason why you have probably never heard a thirsty plant make noises is that the sounds are so high-pitched that very few humans could hear them. Some animals, however, probably can. Bats, mice and moths could possibly live in a world filled with the sounds of plants, and previous work by the same team has found that plants respond to sounds made by animals, too.
To overhear plants, Lilach Hadany at Tel-Aviv University in Israel and her colleagues placed tobacco and tomato plants in small boxes provided with microphones. The microphones picked up any noises made by the plants, even if the researchers couldn’t hear them. The noises were particularly obvious for plants that were stressed by a lack of water or recent cutting.
Plants do not have vocal cords (声带) or lungs. Hadany says the current theory for how plants make noises centers on their xylem (木质部) that transport water and nutrients from their roots to their branches and leaves. Water in the xylem is held together by surface tension, just like water moving through a drinking straw. If an air bubble (气泡) forms or breaks in the xylem, it might make a little popping noise; bubble formation is more likely during dry seasons. But the exact system requires further study, Hadany says.
The team produced a machine-learning model to check whether a plant had been cut or was water-stressed from the sounds it made, with about 70% accuracy. This result suggests a possible role for the audio monitoring of plants in farming and gardening.
To test the practicality of this approach, the team tried recording plants in a greenhouse. Pilot studies by the authors suggest that tomato and tobacco plants are not exception. Wheat, corn and wine grapes also make noises when they are thirsty.
1. What is the new research mainly about?| A．Plants can react to animals. | B．Plants can produce sounds. |
| C．Well-watered plants keep silent. | D．Branchless plants need watering. |
| A．They can create more bubbles. | B．They can feel less stressed. |
| C．They require less nutrient supply. | D．The y need lungs to breathe more. |
| A．Fruit growing. | B．Crop selection. |
| C．Water source protection. | D．Noise pollution test. |
| A．How Plants Are Thirsty | B．When Nature Expresses Itself |
| C．How Plants Cry for Their Needs | D．When Creatures Hear Each Other |
7 . The huge billboard at the side of the highway is no joke; transporting firewood in certain areas is a crime, punishable by a four-thousand-dollar fine. The reason? Emerald Ash Borer disease, or EAB disease, a new addition to the long list of dangerous foreign pest infestations（虫害）on American soil. It was in 2002 when the Emerald Ash Borer beetle（甲虫）was first discovered in Michigan. Not long after, the pest was found in Ohio. Originally from Asia, this green beetle probably found its way to North America through a wooden box made of ash wood and immediately settled into a local ash tree. In little time, the species managed to kill millions of ash trees.
To date, much work is underway to stop ash trees ending up in the same group as elm and chestnut trees, which are all dying out in many areas. Ash Borer Infestations are particularly troublesome because they are difficult to identify until the ash tree is heavily infested. In addition, other ash trees in the area surrounding the source will probably also be infested, making control a hard task.
Researchers are working on many issues related to the control and removal of this harmful beetle. For example, it has been discovered that Asian ash trees are not destroyed by this native borer. It may be that, Asian ash trees have developed genes（基因）to protect them from the insect; therein, perhaps, lies the secret to controlling this pest. Insecticide（杀虫剂）treatment is also being explored on several fronts. Research is underway to determine which insecticides are proving to be the most successful. The proper application of the insecticides is being debated.
However, all possible solutions require a great deal of study and research. In the meantime, careful steps must be taken. Methodical identification of infested trees is taking place. Identified trees are being cut down and destroyed to get rid of the beetle colonies（群）. In the end, this puts a huge drain（消耗）on city budgets, as tree removal can be extremely expensive.
Even though it will be expensive to deal with this problem in the short term, the costs of doing nothing could be far higher, since we could lose an entire species of tree.
1. What can we learn about the Emerald Ash Borer beetle?| A．It is a newly found species. |
| B．It can be used to fight foreign pest infestations. |
| C．It is native to North America. |
| D．It can cause damaging harm to American ash trees. |
| A．They affect Asian ash trees most frequently. |
| B．They are difficult to identify and get rid of. |
| C．They break out at certain times every year. |
| D．They spread slowly in a small area. |
| A．Gene activation. | B．Insecticide use. |
| C．Removing infested trees. | D．Introducing the beetle’s enemies. |
| A．Healthy trees should be relocated and protected. |
| B．Protecting the ash tree should be done at any cost. |
| C．Government budget for tree removal should be cut. |
| D．Measures that have side effects should be avoided. |
