1 . In early October, Travis Gienger transported an enormous pumpkin (南瓜) from his home in Minnesota to the World Championship Pumpkin Weigh-Off in California. His pumpkin set the record for the biggest one ever grown in North America. How do competitive growers get their pumpkins to grow to massive sizes?
Gienger, who teaches horticulture (园艺学) at Anoka Technical College, begins growing his pumpkins in mid-April, starting with seeds that he grows indoors for the first few weeks, when Minnesota’s soil is too frosty.
Depending on the variety, pumpkin plants can grow up to a dozen fruits on a single vine (藤曼) . But to maximize size, growers remove all but one or two of these pumpkins in order to decrease each individual fruit’s competition for resources.
But what exactly happens inside a pumpkin as it grows? Two factors drive natural growth: cell division and cell expansion. Cell division accounts for most of the growth at the beginning of a fruit’s life. This period lasts for about 20 days in pumpkin plants.
| A．Biology has the answers. |
| B．Genetics also influences pumpkin growth. |
| C．The following tips will give you a head start. |
| D．Once it warms up, the plants are transferred outside. |
| E．When it stops, cell expansion will then come into play. |
| F．Growers extend the growth period for as long as possible. |
| G．Growers also remove the weeds in the area for the same reason. |
2 . 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. |
3 . When micro-plastics end up in farm fields, the pollution can damage plant growth. But two young researchers now report that combining fungi (真菌) with certain farm wastes can partly overcome that problem.
May Shin, 20, and Jiwon Choi, 18, met in a research design class at the Fryeburg Academy, a high school in Maine. May had desired to explore how micro-plastics might affect the ecosystem. Jiwon was crazy about plants and fungi. The young scientists cooperated to test how long-lived plastics might affect farm crops.
Scientists have shown certain fungi can aid root growth and a plant’s nutrient uptake. Those organisms are named arbuscular mycorrhizal fungi (AMF). Certain farm wastes, like straw, can provide nutrients to plants and help stabilize their roots. Such wastes are also known as mushroom substrate (基质) and people often grow mushrooms in them.
May and Jiwon planted over 2,000 scallion (大葱) seeds in pots of soil. Half the seeds got soil polluted with micro-plastics. The rest grew in plastic-free soil. The plants then were further divided into four groups. The young scientists added AMF to the soil in one group. Another group had a top layer of mushroom substrate. A third group got both treatments. The last group got none. For three weeks, the pair tracked how many scallions sprouted (发芽) in each group and measured the plants’ height once each week.
About twice as many scallions sprouted in clean soil compared to that containing plastic bits. But among plants surviving in the polluted soil, a combination of AMF and mushroom substrate helped them out. Those getting both treatments grew 5.4 centimeters per week. That was faster than either of the treatments alone or those getting none.
Jiwon and May then looked at the plant roots with a microscope. Where AMF had been added, it grew into those roots. That increased the scallion roots’ surface area, May said, which should promote their uptake of nutrients. So “I see this project as coming up with a sustainable solution for plant growth in polluted soils,” said May.
1. Why did May and Jiwon work together?| A．To see the effects of long-lived plastics on farm crops. |
| B．To find the relationship between plants and fungi. |
| C．To design a research on the growth of plants. |
| D．To explore the way that the ecosystem works. |
| A．To prove the existence of micro-plastics. | B．To compare fungi with farm wastes. |
| C．To tell the advantages of farm wastes. | D．To provide some related information. |
| A．Its purpose. | B．Its design. | C．Its findings. | D．Its reasons. |
| A．By keeping the plants more resistant to pollution. | B．By allowing the plants’ deep area more freedom. |
| C．By making nutrients more available to the plants. | D．By exposing the roots to a larger surface area. |
4 . Both humans and animals possess the ability to cry out for help when endangered or threatened. Plants, as it turns out, can too.
“We found that plants usually emit (发出) sounds when they are under stress and that each plant and each type of stress is associated with a specific identifiable sound,” researchers from Tel Aviv University in Israel wrote in their findings, published in the scientific journal Cell. “While undetectable to the human ear, the sounds emitted by plants can probably be heard by various animals, such as bats, mice, and insects.”
Stressors like dehydration (脱水) and damage to leaves gave rise to the plants’ high-pitched (尖声的) cries, which ranged from 20 to 250 kHz. The bigger the danger, the more frequent a plant’s signals. “Unstressed plants emitted less than one sound per hour, on average,” researcher Lilach Hadany said, “while the stressed plants — both dehydrated and injured — emitted dozens of sounds every hour.”
To catch these sounds, Hadany’s team surrounded tomato and tobacco plants with super-sensitive microphones. They then fed the data into an artificial intelligence program that could tell the difference between the species of plant and the types of sounds produced.
“Our findings suggest that the world around us is full of plant sounds, and that these sounds contain information,” Hadany wrote. She added that to translate that information, we just need the “right tools such as sensors that tell growers when plants need watering.” Doing so, researchers noted, may allow farmers to judge exactly when and where to water crops. Saving water, increasing harvests, and lowering stress for both plant and humankind.
1. What did researchers from Tel Aviv University in Israel find?| A．Creatures tend to cry out for help when in danger. |
| B．Plants can give off sounds when they are stressed. |
| C．Plant sounds can be heard by both animals and humans. |
| D．Plants make the same sound whatever type of stress they have. |
| A．The influence of stress on plants. |
| B．The urgency of relieving stress of plants. |
| C．The possibility of plants emitting sounds. |
| D．The importance of conducting the research. |
| A．To help get rid of plant stress. |
| B．To identify the types of stress. |
| C．To collect sounds emitted by plants. |
| D．To analyze the collected sounds of plants. |
| A．The research is of practical value. |
| B．It’s difficult to understand plant sounds. |
| C．Further research is needed in the future. |
| D．It’s as easy as pie for farmers to grow crops. |
5 . You may have wondered how lavender is used for social anxiety. But first, just what is lavender? Lavender, also known as English or garden lavender, is a herb native to the Mediterranean region. Historically, lavender was used to mummify bodies in Egypt, in baths in Greece and Rome, and for curing the broken skin and mental health purposes. Today, lavender is used as a traditional or complementary remedy for relaxation, to reduce anxiety, and depression, as well as for diseases such as stomach upset and headaches.
No scientific studies have specifically examined the benefits of lavender use for social anxiety disorder. In a 2000 study, Cook and Ernst reported that in general, aromatherapy (芳香疗法) is helpful in reducing anxiety and stress in the short-term. A 2012 study also showed some evidence of the usefulness of lavender taken for anxiety. More research is needed to support the use of lavender for the treatment of social anxiety disorder.
Lavender is usually used in the form of an essential oil as part of aromatherapy. The scent is inhaled, or the oil is applied to the skin, which will benefit the anxious people quickly. Dried lavender can also be used to make a tea or liquid extract. Lavender may also be taken in pill form. Lavender tea can be made by using 1 to 2 teaspoons of dried leaves for 15 minutes in a cup of boiling water. In liquid extract form, no more than 60 drops of lavender should be taken in a day. Before taking lavender in liquid form, you should read the product label and discuss the dose with a qualified health care provider.
There is not enough scientific evidence to safely recommend lavender for children younger than 18 years. Lavender taken by mouth has the potential to increase the risk of bleeding. If you suffer from a bleeding disorder or are taking medicine that may increase bleeding,use caution when taking lavender.
1. What can we know about lavender from paragraph l?| A．It can help deal with mental health problems. |
| B．It was used to preserve dead bodies in Greece. |
| C．It was used to cure stomach upset and headaches. |
| D．It is a herb introduced into the Mediterranean region. |
| A．The treatment for social anxiety disorder. |
| B．The history of aromatherapy reducing stress. |
| C．The benefits of lavender used for mental disorder. |
| D．The researches on the use of lavender for social anxiety. |
| A．By collecting data. | B．By making a list. |
| C．By introducing concepts. | D．By making comparisons. |
| A．It may worsen the bleeding. |
| B．It’s proved to be unsafe for kids of 14. |
| C．Lavender in pill form functions better than that in liquid. |
| D．A dose should be decided according to the product label. |
6 . Take a look at that tree in the local park. What might it be feeling? Could it be thinking? Experiments are exploring the idea of plant cognition (认知), even going so far as to suggest they possess some form of consciousness.
As wild as it sounds, it isn’t a new idea. The field of “plant neurobiology (神经生物学)” began in 2006, aimed at understanding how plants process information from their environment.
It is now clear that plants are capable of complex communication and can sense their surroundings, which were originally dismissed. But advocates of plant consciousness take things further and draw parallels between the electrical signaling that can be found from root to stem and that present in the nervous system of animals. They claim to show that plants are capable of intentionally choosing to perform certain behaviors, of learning and perhaps even having personalities. If plants are experiencing a conscious inner world, they argue, it becomes vital that we find ways to test and understand it.
Extending the concept of cognition to plants would mean a significant shift in our view of the uniqueness of humanity, not to mention how we treat our botanical friends, so the bar of acceptance is high. Researchers rising to the challenge are hoping to explore plants with tools usually reserved for the human brain.
The research can appear persuasive, but it is in its early stage and suffers from repeated failure. Critics say the field is a high guess and that the behaviour can be explained through inborn response.
Whether we decide that plants have cognition may come down to our ability to describe consciousness itself-something we are far from doing. But rather than dismiss the idea, we should welcome the chance to think up new ways to test our understanding of consciousness. It might just improve our grasp of the human mind. At the very least, our trees and plants should benefit from the extra attention-consciously or not.
1. What do supporters of plant consciousness believe?| A．Plants can only perform native reaction. |
| B．Plants can perceive their surroundings and adapt to them. |
| C．Plants possess the same level of consciousness as humans. |
| D．Plants can communicate complicatedly and choose actions deliberately. |
| A．The need to develop tools to test plant cognition. |
| B．The dramatic change in our view of humanity. |
| C．The lack of evidence in the field of plant neurobiology. |
| D．The inability to describe consciousness itself. |
| A．The field is highly based on guesses and has no evidence. |
| B．Researchers are using tools reserved for the human brain to study plant behaviors. |
| C．There is not enough evidence to support the idea of plant consciousness. |
| D．Plants have been proven to possess a form of consciousness. |
| A．Enhancing our understanding of the human brain. |
| B．Developing new ways to test plant behaviors. |
| C．Promoting our relationship with plants. |
| D．Proving the existence of plant cognition. |
7 . Animals can adapt quickly to survive unfavorable environmental conditions. Evidence is mounting to show that plants can, too. A paper published in the journal Trends in Plant Science details how plants are rapidly adapting to the effects of climate change, and how they are passing down these adaptations to their offspring(后代).
Plants are facing more environmental stresses than ever. For example, climate change is making winters shorter in many locations, and plants are responding. “Many plants require a minimum period of cold in order to set up their environmental clock to define their flowering time,” says Martinelli, a plant geneticist at the University of Florence. “As cold seasons shorten, plants have adapted to require shorter periods of cold to delay flowering. These mechanisms allow plants to avoid flowering in periods when they have fewer opportunities to reproduce.”
Because plants don’t have neural(神经的) networks, their memory is based entirely on cellular(细胞的),molecular(分子的),and biochemical networks. These networks make up what the researchers call somatic memory(体细胞记忆). “It allows plants to recognize the occurrence of a previous environmental condition and to react accordingly,” says Martinelli.
These somatic memories can then be passed to the plants’ offspring via epigenetics(表现遗传). “Several examples demonstrate the existence of molecular mechanisms modulating plant memory to environmental stresses and affecting the adaptation of offspring to these stresses,” says Martinelli.
Going forward, Martinelli hopes to understand even more about the genes that are being passed down. “We are particularly interested in decoding the epigenetic alphabet without changes in DNA sequence(序列),”he says. “This is especially important when we consider the rapid climate change, we observe today that every living organism, including plants, needs to quickly adapt to survive.”
1. What adaptations have plants made to shortened cold seasons?| A．They have shortened their flowering time. |
| B．They have got more chances to reproduce. |
| C．They have avoided flowering in cold seasons. |
| D．They have adjusted their environmental clock. |
| A．It is entirely based on neural networks. |
| B．It can help the plants’ offspring to survive. |
| C．It can help relieve environmental stresses. |
| D．It disturbs the plants’ biochemical networks. |
| A．Adjusting. | B．Treasuring. |
| C．Recording. | D．Sharing. |
| A．Plants are smart about flowering time |
| B．Plants can also adapt to climate change |
| C．Environmental stresses challenge plants |
| D．Mysteries of plant genes are to be unfolded |
8 . With no special equipment, no fences and no watering, two abandoned agricultural fields in the UK have been rewilded (重新野化), in large part due to the efforts of jays, which actually “engineered” these new woodlands. Researchers now hope that rewilding projects can take a more natural and hands-off approach and that jays can shed some of their bad reputations.
The two fields, which researchers have called the New Wilderness and the Old Wilderness, had been abandoned in 1996 and 1961 respectively. The former was a bare field, while the latter was grassland—both lay next to ancient woodlands. Researchers had suspected that the fields would gradually return to wilderness, but it was impressive to see just how quickly this happened, and how much of it was owed to birds.
Using aerial data, the researchers monitored the two sites. After just 24 years, the New Wilderness had grown into a young, healthy wood with 132 live trees per hectare, over half of which (57%) were oaks. Meanwhile, the Old Wilderness resembled a mature woodland after 39 years, with 390 trees per hectare.
“This native woodland restoration was approaching the structure (but not the species composition) of long-established woodlands within six decades,” the researchers explained in the study.
Part of this reforestation was done by the wind, and researchers suspect that previous ground disturbance may have aided the woodland establishment—which is good news, as it would suggest that agricultural areas may be reforested faster than anticipated. However, animals—Eurasian jays, thrushes, wood mice, and squirrels—also played an important role in helping the forests take shape. This handful of species provided much of the natural regeneration needed for the forest to develop. Jays, in particular, seem to have done a lot of heavy lifting.
1. What does the underlined word “shed” in Paragraph 1 refer to?| A．Be opposed to. |
| B．Be ashamed of. |
| C．Get used to. |
| D．Get rid of. |
| A．The scale of the woodlands. |
| B．The diversity of the fields. |
| C．The rate of the changes. |
| D．The frequency of the wilderness. |
| A．The woodland restoration was approaching the structure of long-established ones. |
| B．Much of the wilderness of the fields was owed to birds. |
| C．Previous ground disturbance aided the woodland establishment. |
| D．How quickly the fields returned to wilderness over time. |
| A．The essential role of humans in the reforestation. |
| B．The factors that contribute to the reforestation. |
| C．The importance of woodland establishment. |
| D．The threats faced by a handful of wild animals. |
