1 . 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.

2. What can we know about stem cells in plants according to the text?

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.

3. What does the underlined word “propagation” in paragraph 4 mean?

A．Spread.

B．Change.

C．Existence.

D．Self-repair.

4. What does the last paragraph focus on?

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.

2 . Giant pandas are among the most lovable animals alive today. Unlike their relatives, such as the polar bear, pandas don’t eat meat but survive on a diet of only bamboo. So why and how have pandas abandoned their taste for meat to pick up a vegetarian diet?

Pandas today don’t eat meat. However, they’ve kept much of their meat-eating adaptations from times past. Their digestive systems have not changed much from their meat-eating days. Out of the huge 12.5 kg of bamboo they eat in a single day, only about 17% of it is digested. To survive, pandas eat large amounts of bamboo while having a low-metabolic (新陈代谢的)，lazy lifestyle to make up for the poor energy return.

The giant panda’s shift to a vegetarian diet is in line with the inactivation of a specific gene-Taslrl, which provides them with the ability to taste certain amino acids (氨基酸) abundant in meat. Its inactivation in pandas would lead to their dietary change.

Pandas have evolved to a great degree to cope with their relatively recent bamboo-eating lifestyle. Pandas must seize long and thin pieces of bamboo shoots. To assist with this, they have developed a long “fake-thumb” (伪拇指). So giant pandas have six fingers in each paw which provides better support for them to seize object such as bamboo in one paw quickly. Researchers have found that the surface of the panda’s tongue is different. While other bears and many meat-eating animals have smooth tongues, pandas have evolved tiny projections on the surface of their tongues that serve to file down food. This is especially useful for pandas as they remove the outer cover of bamboo.

Time will tell if pandas will adapt and survive, go back to eating meat, or disappear in the wild. Whatever the future holds, we can be grateful that, for the time being, we get to share our planet with these adorable animals.

1. Why are the numbers mentioned in paragraph 2?

A．To illustrate the variety of food.

B．To represent the evolutionary rule of pandas.

C．To describe the changes of living environment.

D．To show the ineffectiveness of digestive system.

2. What caused pandas’ change in diet?

A．The low-metabolic ability.

B．The amino acids in meat.

C．The Taslrl gene’s inactivation.

D．The supplies of bamboo.

3. What does the underlined word “this” in paragraph 4 refer to?

A．Seizing bamboo shoots.

B．The low energy return.

C．Developing more fingers.

D．The vegetarian diet.

4. Which aspect of pandas does paragraph 4 focus on?

A．The preference for bamboo.

B．The evolutionary feature in eating.

C．The unique lifestyle.

D．The special appearance.

3 . You look up at the sky on a clear and dark night, you’ll see more stars than your eyes can count. Most of these stars have planets, similar to our own, orbiting them. With so many celestial bodies floating out in space, you can’t help but question whether other forms of life exist in the universe. And if that’s the case, is it possible to contact them?

Science is still somewhat divided on this issue. Currently, no evidence exists to suggest that intelligent life exists elsewhere in the universe. Yet with an estimated one trillion planets in our galaxy alone, it seems highly likely that Earthlings aren’t the only intelligent creatures out there. Some claim that life can only develop under perfect circumstances, and Earth is perhaps the only example of this. Other scientists object to this claim, and point out that even on Earth, life can find a way under the most extreme circumstances.

Some people believe that aliens have already visited our planet, but this information is being kept secret by governments. The most famous incident of this kind occurred in Roswell, New Mexico in 1947. On that date, many residents reported seeing an unusual flying disc streak through the sky, before it crashed in a field. When the military heard about the crash, they quickly sealed off the area. A few hours later, the army base announced that it had recovered a flying disk. Shortly after, this statement was retracted and it was said that it was a weather balloon that crashed. However, years later one local mortician even claimed that the military had him secretly perform an autopsy on a dead alien body.

Others believe that there certainly are other life forms out there, but the distance between us is too great. Even if we could somehow create a spaceship that travels at the speed of light, it would still probably take several lifetimes to reach them. Then again, we might never have to do this if aliens reach us first.

1. Why do some scientists think there is life on other planets?

A．Because an unusual flying disc was ever witnessed.

B．Because life exists despite extreme conditions as those on the Earth do.

C．Because the government’s statement seemed suspicious.

D．Because there are a great number of planets in the universe.

2. What does the underlined word “retracted” in paragraph 3 mean?

A．Examined again to guarantee the correctness.	B．Emphasized again to persuade people.
C．Formally taken back what has been said.	D．Seriously criticized due to poor evidence

3. Which of the following might be the best title for the text?

A．Are we alone in the universe?	B．Is it possible to contact aliens?
C．Intelligent life in the universe.	D．Planets floating out in space.

4. How does the author sound in the passage?

A．Objective.

B．Humorous.

C．Cautious.

D．Anxious.

4 . 阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。

When I arrived home from school, night was falling. A call came from the public: a bird of unknown species was being attacked by a group of noisy children in his front garden. He scared them off and grabbed their victim. I immediately called for my classmate Jack to the spot.

We were standing in front of a stranger’s house in an unfamiliar street, rescue box in hand. My head full of instructions to follow. “The bird would be our first test as a volunteer wildlife rescuer!” Jack said excitedly. We had completed the two-day intensive training course the previous month and learned the basic skills of rescuing animals in various situations.

But we were anxious, too. After all, it was the first time for us to rescue a bird. Would I be able to transfer the bird neatly into my rescue box? Many worries flashed in my mind. Sensing my unease about the act ahead, Jack said, “These things are pretty easy to deal with!”

I was wondering what kind of bird it was when a kind-looking man appeared and led us inside to see our very first patient. I lifted the edge of the shoe box very slightly to see an angry-looking bird standing to attention on very thin and long legs, together with a slice of banana and a small dish of water. He didn’t know its true name but the folks called the creature Red Fan. “It’s eaten some banana,” said the man proudly. The poor soul seemed rather nervous, so l decided not to grab it by hand but just transfer the whole shoe box into my rescue box.

Back home, we could only see some minor injuries in the left wing, but there was no blood on its feathers. Jack managed to treat the injuries with some iodophor (碘伏药水). We assessed its condition to find out if it was appropriate to release the bird the next day. How could we help it spend the night peacefully? We hadn’t seen this species of bird before, let alone its habits.

注意：
1. 续写词数要求应为150左右；
2. 请按如下格式在答题卡的相应位置作答。

“Why not do a search on the Internet?” suggested Jack.

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The next day, we were glad to see the bird was well enough.

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5 . 阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。

I must admit, I haven’t always liked animals. In fact, I distrusted them greatly while growing up, and I still fear the ones I don’t know personally. What set my beliefs in stone was being attacked—not once but many times, including the summer after second grade when I was bitten by a rabbit. Then, when I was nine and riding my dirt bike down the road, a large dog charged me and tried to bite my ankle. After all those negative experiences, there was one thing I knew for sure: All creatures, great and small, were no friends of mine.

After college in California, I returned to live the single life in Las Vega. Then I met Lisa. In no time at all, we fell in love, married and moved into a new house. Despite my avoidance of animals, Lisa had a dog called Bailey. Bailey didn’t like me, but he tolerated my existence once he realized I wasn’t going anywhere.

Things changed as spring came. We welcomed a new member of our family: our son Evan. One evening Evan grabbed hold of the dog’s tail. The irritated dog paused and turned to look at his stuck tail but waited patiently until being released. Still the stories I’d heard of animals attacking babies worries me.

Then my worst fear occurred. I sat on the couch (沙发) reading after a long day while my wife worked at the dining-room table paying the bills. I saw Evan crawl across the family-room carpet as he made his way behind the couch. One minute, all was quiet and then Bailey entered the room and headed to where Evan had crawled. I nearly jumped out of my skin when I heard the dog start a fearful barking behind me.

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。

Throwing the book away, I rushed around the couch with great fear.

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Having witnessed our dog killing a scorpion (蝎子) and saving my son, I was speechless.

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6 . A video circulated on social media earlier this year, showing a tourist opening the door of a vehicle, reaching out an arm and attempting to stroke a passing lioness. The lioness shrugged him off, but it could have easily gone horribly wrong.

Reckless behaviour around wildlife risks the safety of both people and animals. People risk being attacked, mauled (撕咬) and possibly killed, while animals can be harmed, removed or put down, irrespective of whether they were only defending themselves. Animal attacks can also cast a destination in a negative light, causing temporary closures or scaring off visitors. All just so someone could boast that they had stroked a lion or captured a moment on a camera phone.

“Tourists are getting more and more reckless around wildlife and the source of the problem is social media.” says wildlife photographer Anette Mosshachers. “People risking their lives or doing stupid things with wildlife are after ‘likes’ and followers, something to show off on social media,” says Mossbacher. “The greater the risk, the more ‘likes’ they get. With some clients, it seems like a sickness or addiction.”

Yet social media is not entirely to blame. People have always taken risks for an experience. Foolish behavior and a tendency to get cocky around dangerous animals must have been around since the dawn of humanity. A hunger for attention online might drive some of the current madness, but some individuals might be trying to recreate a piece of the action they have seen on television. Perhaps the adrenaline (肾上腺激素) rush when close to wild animals causes an evaporation of common sense.

“There’s a worrying lack of awareness that animals several times our size, weight, speed and strength can easily hurt us,”says wildlife photographer David Lloyd. “I don’t think parks are doing enough to raise awareness. Tourists need to know how their presence can affect wildlife. A good example is cheetahs (猎豹) on vehicle rooftops. It may be a thrill for the bystanders, but the consequences if a mother cheetah falls off would be severe. She would no longer be able to hunt, so her cubs could easily starve.”

“People aren’t getting the education about why they need to stay away from wildlife, including avoiding diseases, keeping people secure and letting wildlife be wild,” says Philip Muruthi, vice president of species conservation and science for the African Wildlife Foundation. “We need to educate tourists through signs, pamphlets and frontline drivers. We should stick to guidelines, and there needs to be enforcement through the law.”

1. What can we learn about reckless behaviour around wildlife?

A．It harms tourists more than animals.

B．It enables tourists to get intimate with animals.

C．It may bring more profits to a tourist destination.

D．It may get animals killed for defending themselves.

2. As for Mossbacher’s opinion on what drives people’s reckless behavior, the author is______.

A．sympathetic	B．disapproving
C．doubtful	D．indifferent

3. What does the underlined word “cocky” in Paragraph 4 probably mean?

A．Selfish.	B．Frightened.
C．Arrogant.	D．Shocked.

4. What can we conclude from the passage?

A．Parks are expected to take more responsibilities for educating tourists.

B．Raising tourists’ awareness means stressing the danger of animals to them.

C．More regulation of the tourist industry is the key to raising tourists’ awareness.

D．Penalties rather than education can stop people taking silly risks around wildlife.

8 . Baby seabirds that have not yet hatched communicate with their siblings (兄弟姐妹) in neighbouring eggs by vibrating (震动) their shells, scientists have discovered.

A study of yellow-legged gul s revealed one of the known examples of embryonic (胚胎期的) communication. When exposed to the alarm calls of an adult bird responding to a predator (捕食者) , developing chicks apparently were able to convey the presence of danger to their nest mates by vibrating inside their eggs.

The team collected 90 yellow-legged gull eggs from Sálvora Island and sorted them into nests of three. When the eggs were six days off hatching, two of the three eggs in each nest were temporarily removed from the nest and exposed to either a recording of a predator alarm call or white noise each day until the chicks hatched. The noise was delivered four times a day at random for three minutes at a time. The third egg from each group remained in the nest.

It was found that the embryos responded to the external alarm calls by vibrating or and vocalizing (发声) less —   and that this in or matin appear d to be passed on to the third nestmate. It was seen to copy the vibrations. It also underwent genetic changes and had an increase in the production of stress hormones (荷尔蒙).

“This kind of communication — embryo to embryo — can generate developmental changes that can have potential benefits to the birds after hatching,” said Noguera, the lead author of the study.

A rise in stress hormones makes birds more aware of their surroundings after hatching. When hatched chicks were exposed to alarm sounds, it was found that those who had listened to the noises previously in the egg were quicker to run away and hide.

Noguera said the phenomenon was likely to occur in other bid species. His team now plans to investigate whether the chicks are able to pick up other clues about their external environment before hatching, such a show many other eggs are in the nest.

1. What do the un hatched birds mean to do by vibrating shells?

A．Fight with a predator.	B．Warn others of danger.
C．Play with their nest mates.	D．Seek care from adult birds.

2. What is Paragraph 3 mainly about?

A．The findings of the experiment.	B．The process of the experiment.
C．The subjects of the experiment.	D．The theoretical base of the experiment.

3. What’s the benefit of developing chicks’ sharing information?

A．It makes them mature earlier.

B．It allows them to develop physically.

C．It strengthens bonds with their siblings.

D．It helps them adapt to life after hatching.

4. What does Noguera mainly talk about concerning the research in the last paragraph?

A．Its appeal to the public.

B．Its practical application.

C．Expectations for future studies.

D．Scientists with new perspectives.

9 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
Space Station Rice Tests Show Promise

Chinese astronauts have successfully grown rice seedlings (幼苗) onboard the Tiangong space station.

There have been other rice     1     (experiment) in space. But the one being conducted on Tiangong is the first of     2     (it) kind that aims to produce the complete life cycle of the plant, which begins with a seed and ends with     3     mature plant producing new seeds.

China launched the Wentian space laboratory into orbit on July 24. The space lab, which weighs 23 metric tons and is 17.9 meters tall, is the country’s     4     (large) spacecraft to date. Onboard     5     (be) eight experimental payloads, including the one for the rice experiment.

“We want to investigate how microgravity affects the plant flowering time on the molecular (分子的) level     6     whether it is possible to use the microgravity environment     7     (control) the related process,” said Zheng Huiqiong, a researcher at the Chinese Academy of Sciences. Flowering is a     8     (vital) important stage for plant reproductive development.

“If we want to land on and explore Mars, food     9     (bring) from Earth is not enough for the astronauts’ long journey and mission in space. We have to find a sustainable food source     10     long-term space explorations,” Zheng said.

10 . I met the Man of the Trees in summer ten years ago, when I was visiting Uncle Jita.

Those were difficult times. People were cutting down our forest, and there was often flooding. Sometimes our water supply was dirty. When our pump(水泵)did have clean water, we had to wait in line for ages. When the pump wasn’t working, we had to walk five kilometres to the closest stream.

But I was happy. I was going to see my favorite uncle. When the day finally arrived, Dad drove me to Uncle Jita’s house and left. Once he saw me, Uncle Jita announced, “Tomorrow we’re going to explore a magical place. Here is my camera, Amy. You can take photos of what you see.”

The following day, we woke up and left early on a boat. The trip was exciting. But when we got off, there was ... nothing in front of us. “I don’t want to take pictures of this,” I complained.

Uncle laughed,“Start walking, Amy. I promise you’ll be surprised.” After some time, I could see the outline of a forest in the distance. A little closer, there was a man waving to us.

“That’s Kabir. The forest you see is his. He planted every single tree.” As we walked towards Kabir, Uncle explained that thirty years ago, the whole area was a wasteland. But one day Kabir decided to change all that and started planting trees. Thanks to him, part of the wasteland is now a paradise(天堂).

Uncle introduced me to Kabir, who had gray hair and a determined face. “Jita told me you like animals. Are you ready to see some?” he asked. “Of course!” I replied. We continued walking and soon were under the trees. I turned my head and was amazed at the difference between the two places. All because of the efforts of one man.

Like Uncle said, Kabir’s forest was magical. We saw deer, rhinos, and even tigers. During lunchtime, Kabir explained how, by planting trees, it was possible to stop the land from eroding(侵蚀).

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。

Hearing this, I turned to my uncle, ^“I think we can plant trees too ”

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In the years that followed, people in our village worked hard to carry out our plan.

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