热点话题04 科学家从皮肤细胞中培育出人类卵细胞——生物科学技术（阅读理解专练）英语高考复习通用版

热点话题04 科学家从皮肤细胞中培育出人类卵细胞——生物科学技术 目录 时文精读------------------------------------------------------------精选外刊原创阅读理解 【原创·阅读理解】 【课标词汇积累】 【课标词汇训练】 【参考译文】 好题精练----------------------------------------------------------精选名校及联考话题专练 【阅读理解】 【阅读7选5】 【完形填空】 【语法填空】 时文精读 读 【话题·导语】 科学家从皮肤细胞中培育出人类卵细胞。 【原文·时文阅读】 文章来源：https://www.sciencenews.org/article/human-egg-cells-from-skin-cells A technique used in cloning combined with fertilization and a bit of chemical coaxing caused human skin cells to produce eggs able to give rise to early human embryos, researchers report September 30 in Nature Communications. The effort is the latest attempt to make eggs and sperm from human cells. Researchers have already succeeded in making these important cell types from many types of animals, including pandas. But producing human eggs and sperm has proven elusive. 窗体底端 Such technology may one day treat infertility for women who no longer have eggs because of age, early menopause or previous cancer treatments. Same-sex male couples may also be able to use the technique “to have, potentially, a child that’s genetically related to both partners,” says reproductive endocrinologist Paula Amato of Oregon Health & Science University in Portland. For now, the technique “is too inefficient and high risk to apply immediately to clinical application,” says stem cell researcher Katsuhiko Hayashi of the University of Osaka in Japan. Hayashi was not involved with this effort but previously reprogrammed tail cells from two adult male mice into eggs and sperm. Those reprogrammed cells gave rise to healthy mice that had two biological fathers and were able to have offspring of their own. A version of the new technique also works in mice, Amato says. “Usually, things that we can get to work in mice eventually work in humans.” At least, in making stem cells it does. Amato and colleagues removed the nucleus（细胞核） from a human egg cell and replaced it with the nucleus of a type of skin cell called a fibroblast（细胞核移植技术）. That step, called somatic cell nuclear transfer, is the same first step used in cloning Dolly the Sheep and many other species.   But the researchers weren’t trying to make a human clone. They wanted to make an egg cell, which has 23 chromosomes（染色体）. That’s half the number of chromosomes as most other cells in the body, which carry a set of 23 chromosomes inherited from the mother and 23 from the father. Cells that will give rise to eggs and sperm go through a type of cell division called meiosis（减数分裂）, which halves the number of chromosomes. In that process, each chromosome pairs with its counterpart from the other parent and swaps some DNA. The cell then divides, pulling one half of each pair into daughter cells. Then, when eggs and sperm get together, they produce a zygote（受精卵） with 46 chromosomes that will divide and make every cell in the body. But the cloned egg already had 46 chromosomes. With mice, Amato and colleagues just fertilized the cloned egg with sperm. That caused the egg to jettison half its chromosomes, producing an embryo with the correct number of chromosomes. The human eggs, though, didn’t extrude half their chromosomes when fertilized. So the researchers had to add chemical persuasion in the form of a molecule called roscovitine. That molecule allowed the winnowing of chromosomes to begin.   Some of the fertilized eggs made early human embryos, but many did not. “That’s probably, we think, because they had an abnormal number of chromosomes,” Amato says. These failed would-be eggs kicked out half their chromosomes, on average, but not the right half. None of the embryos were allowed to develop beyond the blastocyst（胚囊） stage, growing for about six days. Many stopped developing at earlier stages. None of the embryos ended up with the correct sets of chromosomes so ultimately were not viable. For instance, one embryo had 48 chromosomes instead of 46. That embryo had all 23 chromosomes from the sperm, but a mishmash of 25 chromosomes from the skin cell. Some chromosomes were present in a single copy, while others had two copies, and other chromosomes were missing entirely. The unequal divisions probably resulted because the chromosomes paired randomly instead of with their specific mate as they would in normal meiosis, Amato says. “It was not the outcome we wanted, really, but it was more proof-of-concept. ‘Hey, we can kind of make this process happen now,’” Amato says. The team is working to get the chromosomes to divvy up properly but she estimates at least a decade before the technique could be tested in clinical trials. Even then, such trials would probably not take place in the United States, which prohibits genetic modification of human embryos, she says. The new technique has a drawback in that it requires donor egg cells for the cloning step, Hayashi says. Reprogramming as he and colleagues have done does not need egg cells to make other egg cells. Still, he says, “this technology has made a significant breakthrough in halving the human genome.” He predicts “new technologies will stem from this achievement.”  【原创·阅读理解】 1.What does the underlined word in the second paragraph mean? A.difficult to find B.successful to solve C.fail to do D.easy to make 2.What was the possible reason why did Amato’s experiment fail? A.Because the American government didn’t support the research. B.Because the fertilized eggs had an abnormal number of chromosomes. C.Because his team didn’t collect enough money for the experiment. D.Because his team didn’t have theory to support the experiment. 3.Which is correct according to text? A.Hayashi thinks that the new technique is useless. B.Making egg cells from skin cells from many types of animals is successful. C.Hayashi is a member of the Amato’s experiment. D.Amato predicts ten years before the technique could be tested in clinical trials. 4.What is Amato’s attitude to the technique? A.confident B.skeptical C.negative D.indifferent 【课标词汇积累】 1.technique n.技术, 技能 The teacher demonstrated a new memorization technique by using colorful mind maps to help students remember historical events more effectively. 老师展示了一种新的记忆技巧，通过使用彩色思维导图帮助学生更有效地记住历史事件。 2.combine v.使结合，混合, 联合, （使）联合；（使）合并n.联盟，集团 The science project required us to combine different chemicals to observe the reactions, which was both exciting and educational. 科学项目要求我们将不同的化学物质混合以观察反应，这既有趣又有教育意义。 3.previously adv.事先, 以前, 仓促 Previously, our school library only had a few outdated books, but now it's filled with new novels and reference materials.以前，我们学校图书馆只有几本过时的书，但现在堆满了新小说和参考资料。 4.attempt v. 努力，尝试，企图 n. 努力，尝试，（杀人）企图 Our class will attempt to organize a charity bake sale to raise funds for the local animal shelter. 我们班将尝试组织一场慈善烘焙义卖，为当地动物收容所筹集资金。 5.potentially adv. 潜在地；可能地 Staying up late to play video games can potentially affect your concentration in class the next day. 熬夜玩电子游戏可能会影响你第二天的课堂注意力。 6. reprogramme v. 再次（重新）设定程序 After failing the midterm, I decided to reprogramme my study habits by creating a strict schedule and sticking to it.期中考试不及格后，我决定重新调整学习习惯，制定严格的时间表并坚持执行。 7.modification n. 修改，修正，变更，改良，改进 The school cafeteria made a healthy modification to its menu by replacing fried foods with grilled options. 学校食堂对菜单做了健康调整，用烤制食品替代了油炸食品。 8.randomly adv. 随便地，未加计划地 The principal would randomly visit classrooms to check if students were focused during lessons. 校长会随机抽查教室，看学生上课是否专注。 9.abnormal adj. 不正常的，异常的；畸形的 It was abnormal for the usually punctual student to be late three days in a row, so the teacher asked if everything was okay.一向守时的学生连续三天迟到很不寻常，所以老师询问是否一切正常。 10.persuasion n. 劝说，说服（力）；信仰 The student council used creative persuasion tactics like free snacks to encourage more students to attend the after-school lecture.学生会用免费零食等创意劝说策略鼓励更多学生参加课后讲座。 【课标词汇训练】 根据语境，从上面的“课标词汇”中选用合适的单词及其正确形式将句子补充完整。 1.The basketball coach taught us a special shooting _____________ that improved our accuracy during practice.篮球教练教了我们一种特殊的投篮技巧，在训练中提高了我们的命中率。 2.We decided _____________ our ideas for the school festival and create a unique performance that included both dance and drama.我们决定将校园节的想法结合起来，创作一个包含舞蹈和戏剧的独特表演。 3.I had _____________ struggled with math, but after extra tutoring sessions, my grades improved significantly.我之前数学很差，但在额外辅导课后，成绩显著提高了。 4.During the sports meet, John made a brave _____________ to break the school's long jump record, landing just a few centimeters short.运动会上，约翰勇敢尝试打破学校的跳远纪录，只差几厘米就成功了。 5.Joining the debate club could _____________ help shy students build confidence in public speaking.参加辩论社可能帮助害羞的学生建立公开演讲的信心。 6.The computer teacher showed us how _____________ the robot to complete an obstacle course instead of just moving in straight lines.计算机老师教我们如何重新编程机器人，让它完成障碍路线而不仅是直线移动。 7.Our English teacher suggested some _____________ to our essay outlines to make our arguments clearer.英语老师对我们的作文提纲提出了一些修改建议，使论点更清晰。 8.For the group project, our teacher _____________ assigned teammates to ensure everyone worked with different classmates.分组作业时，老师随机分配组员以确保每个人和不同的同学合作。 9.The _____________ heat wave in October forced our school to cancel outdoor PE classes for safety reasons.十月的异常热浪迫使学校出于安全取消户外体育课。 10.After much _____________ from the art teacher, the shy student finally agreed to display her paintings in the school exhibition.经过美术老师的多次劝说，害羞的学生终于同意在学校展览中展示她的画作。 【参考译文】 研究人员在9月30日的《自然-通讯》中报告称，通过结合克隆技术与体外受精，并辅以化学诱导手段，成功使人类皮肤细胞产生能够发育为早期人类胚胎的卵细胞。 该研究是人类细胞制造卵子和精子技术的最新突破。此前科学家已从包括大熊猫在内的多种动物细胞中培育出配子，但人类配子的制备始终面临挑战。 这项技术未来或可帮助因年龄、早发性绝经或癌症治疗而卵子枯竭的女性解决不孕问题。"同性男性伴侣也可能通过该技术获得与双方均有遗传关联的后代，"波特兰俄勒冈健康与科学大学的生殖内分泌学家保拉·阿马托表示。 但大阪大学干细胞研究者林克彦指出，当前技术"效率过低且风险过高，无法立即投入临床应用"。林克彦虽未参与本研究，但曾将成年雄性小鼠尾部细胞重编程为卵子和精子，并成功培育出拥有双父系基因的健康小鼠后代。 阿马托团队采用体细胞核移植技术——即克隆多利羊的技术路径——将皮肤成纤维细胞的细胞核植入去核人类卵细胞。与克隆不同，研究者旨在制造仅含23条染色体的卵细胞。正常配子形成需经历减数分裂，使染色体数量减半并完成基因重组。但克隆卵细胞初始携带46条染色体，小鼠实验中直接受精即可触发染色体减半，而人类卵细胞需依赖化学药物罗可维汀诱导。 实验显示，部分受精卵可发育至囊胚阶段（约6天），但因染色体分配异常均未存活。典型失败案例中，一个胚胎含有精子提供的完整23条染色体，却混杂了皮肤细胞来源的25条染色体，呈现单拷贝、双拷贝甚至完全缺失的混乱状态。阿马托解释，这种异常源于染色体随机配对而非正常减数分裂的特异性配对。 "虽未达预期目标，但验证了技术可行性，"阿马托表示。团队正着力解决染色体精准分配难题，预计至少需十年才可能开展临床试验。鉴于美国禁止人类胚胎基因编辑，相关试验或将在其他地区进行。 林克彦指出该技术仍需捐赠卵细胞作为核移植载体，不如其团队开发的直接重编程方案便捷。但他承认："这项研究在人类基因组减半技术上取得重大突破，必将催生更多衍生技术。" 好题精练 练 Passage1阅读理解 Known for its role in Game of Thrones (《权力的游戏》), the dire wolf (冰原狼) went extinct over 10,000 years ago. On April 7, the US company Colossal Biosciences announced restoring this species via de-extinction — a historic first. Time magazine said scientists studied fossils (化石) such as a 13,000-year-old dire wolf tooth and a 72,000-year-old ear bone and compared their genes to those of gray wolves to discover differences. They edited 14 key genes in gray wolf blood cells to match dire wolf traits, implanting modified cell’s nuclei (核) into surrogate (代孕) dogs’ eggs. The babies, larger than gray wolves, now live in a preserve. They behaved like wolves by howling at two weeks old. But “we have not seen them attempt to hunt live prey”, Colossal’s Paige McNickle told Time magazine. Some scientists have criticized the project. Professor Nic Rawlence from Otago University questioned using fossil DNA, calling it too damaged to use. “Ancient DNA is like if you put fresh DNA in a 500 degree oven overnight, it comes out like dust,” Rawlence told the BBC． He argued Colossal actually only created “a hybrid (杂交品种)” — a gray wolf with dire wolf features. Colossal isn’t just reviving the dire wolf. Their list includes the woolly mammoth, dodo and Tasmanian tiger. Their mission goes beyond de-extinction: they also use the same technique to prevent species in danger from disappearing. For example, they brought back four red wolves, an endangered species, in the same way of restoring the dire wolf. The Center for Biological Diversity predicts that 30% of the planet’s genetic diversity could be lost by 2050. Colossal CEO Ben Lamm argues that genetic engineering is crucial to prevent this loss. Yet some warn there could be consequences. Introducing new species can cause invasive species, while cloning often leads to health problems in animals and surrogates. 1．How did scientists try to restore the dire wolves? A．By obtaining DNA from living dire wolves. B．By hybridizing different modern wolf species. C．By studying fossils of dire wolf and surrogating. D．By using complete DNA of dire wolves to clone. 2．What can be learned about the “restored” dire wolf babies? A．They exhibit some wolf-like behaviors. B．They have already begun hunting live prey. C．They are bigger in size than adult gray wolves. D．They are completely the same as the ancient dire wolves. 3．Why does the author mention red wolves in the 5th paragraph? A．To illustrate the variety of revived species. B．To highlight the importance of biodiversity. C．To contrast with the dire wolf’s revival process. D．To show Colossal’s broader conservation efforts. 4．What is the author’s attitude towards the de-extinction? A．Opposed and critical. B．Objective and cautious. C．Supportive and optimistic. D．Humorous and unconcerned. 【词汇积累】 1.extinct adj. 灭绝的；废除了的 2.historic adj. 历史（性）的；有历史记载的 3.implant vt. 移植；灌输；植入，插入vi. （受精卵）着床；被移植 4.preserve v. 保持；保护；保险；腌制n. 蜜饯；果酱；腌菜 5.criticize v. 批评，指责；评价，批判 6.endangered adj. （动物、鸟类等）濒危的，濒于灭绝的 7.diversity n. 多样性，多元性；差异，不同 8.crucial adj. 至关重要的，关键性的 Passage2阅读理解 An ambitious plan to genetically engineer a version of the woolly mammoth (长毛猛犸象), a giant that disappeared 4,000 years ago, is making some progress. A new biosciences and genetics company, Colosal, has raised $15 million to create a mammoth hybeid that looks exactly like its extinct counterpart. The goal isn’t to clone a mammoth, but to create, through genetic engineering, a living, walking elephant-mammoth hybeid. The scientists revealed they had reprogrammed cells from an Asian elephant, the woolly mammoth’s closest living relative. These changed cells can grow into any kind of elephant cell. The research team has analyzed the than 50 changes to the genetic code of the Asian elephant to give it the characteristics it needs to survive and thrive in the Arctic. These characteristics include a 10-centimeter layer of insulating (绝缘的) fat, five different kinds of hair including some that is up to a meter long, and smaller ears that will help the hybrid tolerate the cold. Colossal believes that bringing the woolly mammoth back to life could possibly help restore the fragile Arctic tundra (冻原) ecosystem, which is at risk as the world warms. The company has claimed that mammoths, if they should return to their natural habitat in the Arctic in sufficient numbers, would help slow down frozen soil melting. Some scientists believe that, before their extinction, animals such as mammoths and horses kept the earth frozen underneath by walking on the grass, knocking down trees and pressing snow tight. One small study in Siberia published in 2021 suggested that the presence of large mammals such as horses and reindeer resulted in lower soil temperatures in the protected area where they were kept compared with land outside that area. Colossal also announced plans to being some other animals back to life such as the Tasmanian tiger in 2023 and the dodo in 2024, but its work on the mammoth has been going on longest. 5．What does the underlined word “counterpart” in the first paragraph refer to? A．Endangered animal. B．Fellow species. C．Cloned elephant. D．Extracted cell. 6．What can we learn about the hybrid? A．It is visually similar to the Asian elephant. B．It can grow into any types of elephant cell. C．Thick fat and smaller ears help it endure the severe weather. D．Long hair like a woolly coat keeps it from the cold and attacks. 7．Why does the author mention the study in Siberia in Paragraph 3? A．To illustrate the possibility of reintroducing mammoths to their natural habitats. B．To compare different kinds of nature reserves where large mammals were kept. C．To indicate the link between the extinction of large mammals and climate change. D．To show the potential impact of returning mammoths to the Arctic on the ecosystem. 8．What can we infer from the last paragraph? A．The project on bringing back the mammoth costs the most. B．The Tasmania tiger and the dodo are also long-dead animals. C．Colossal needs increased investment to advance the projects. D．Colossal is completely confident in its technology and scientists. 【长难句分析】 【文章原句】Colossal believes that bringing the woolly mammoth back to life could possibly help restore the fragile Arctic tundra (冻原) ecosystem, which is at risk as the world warms. 【句式分析】 这个句子是一个复合句。That后是宾语从句，which is at risk as the world warms是宾语从句中的非限制性定语从句。 【翻译】Colossal认为，让猛犸象复活可能有助于恢复脆弱的北极苔原生态系统，随着全球变暖，这个生态系统正面临风险。 Passage 3 阅读七选五 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。 Four Rules for Successful Plant Cloning Plant growers have two choices when it comes to starting new plants: growing from seed, or plant cloning. And plant clones offer advantages that growing plants from seed can’t offer. 1 , and as long as you do the cloning yourself, you know who the mother plant is and how your clones will grow, yield, and get you high. But it’s an art and science to plant cloning. Take your plant cuttings from a healthy motherplant. Plant cloning gives you genetic copies of your motherplant. 2 , your clones get the best start possibly. Avoid using motherplants that are sick, or that are plagued with pests. 3 . Most plant clones prefer temperatures slightly higher than your ideal grow room temperature, and they don’t like a day and night cycle with a temperature drop at night. That’s why most growers root their cuttings under lighting that stays on 24 hours a day. The lighting itself creates temperature stabilization. Temperatures between 74-77 degrees F are the range you want. Clones like high humidity(湿度). Your cuttings need a humid environment in the 75-95% humidity range until they’ve created roots and are able to intake water through them. That’s why many plant cloners use humidity covers. 5 , they’ll die. Use sterile(无菌的) equipment and materials. You already figured out that your scissors, knife, or other tools for cutting clones has to be clean. But you also want to make sure you trays, cloning covers, and root zone media are clean and sterile too. Don’t reuse cloning cubes or cloning powders and gels. 5 . When you follow these plant cloning tips, your clone success rate should be nearly 100%. A．Start fresh every time B．Use kind LED lighting C．Give your plant clones consistent climate D．Growing from clones you’re sure to have all females E．If you’re taking 20 clones and seeing only 10 of them survive F．Until your clones have functioning roots, if they’re in dry air G．If your motherplants are strong, healthy, and have potent genetics Passage 4 完形填空 Like anything built by evolution, the human body has many downsides, teeth without exception. Adult humans only get one set of teeth, which must last about 60 years. However, a(n) 1 of poverty, sugar-rich diets and poor hygiene means 2.5bn people globally suffer from tooth decay, in which acid produced by mouth-living bacteria eats away the hard enamel (牙釉质) that 2 the outside of a tooth, leading to further infection and damage. Once decay has set in, all a dentist can do is to fill the gap with artificial filling. But in a paper published in Cell, Hannele Ruohola-Baker, a stem-cell biologist at the University of Washington, and her colleagues offer a possible 3 . Stem cells have the 4 to turn themselves into any other type of cell in the body. It may soon be possible, the researchers claim, to use those 5 cells to regrow a tooth’s enamel naturally. The first step was to work out how enamel is produced. As enamel-making cells, known as ameloblasts, disappear soon after a person’s adult teeth have finished growing, the researchers 6 samples of tissue from human foetuses (胚胎), which contain plenty of functioning ameloblasts. 7 , they checked to see which genes were especially active in the enamel-producing cells. It turned out that genes designed to bind to calcium were particularly busy. 8 that information, Dr Ruohola-Baker and her colleagues next checked to see whether the stem cells could be persuaded to 9 ameloblasts. The team devised various drugs designed to activate the genes expressed in functioning ameloblasts. That worked, with the engineered ameloblasts producing the same proteins as the natural sort. For now, the work is more concept than a medical treatment. The next step is to boost enamel production further, with a view to 10 beginning clinical trials. The hope is that, one day, medical versions of the team’s findings could be used as biological implants, to 11 a patient’s decayed teeth. Stem-cell-based therapies are not the only ones heading to clinical trials. Another treatment, known as biomimetic repair, involves rebuilding the tooth crown using synthetic (人工合成的) proteins, which are similar, but not quite 12 , to human enamel. The proteins could be included in toothpaste and even cough drops. But synthetic formulations can be less 13 than human enamel. It will take time for either technology to become reality. One question is how durable the enamel made by stem-cell-derived ameloblasts is. Another is how best to deliver the stem cells to a patient’s mouth. But these findings are 14 . As any dentist will tell you, prevention is better than cure. 15 , a better cure would be always welcome. There is no doubt that this research offers a new prospect for future dental care. 1．A．combination B．absence C．application D．coincidence 2．A．contains B．coats C．floats D．fills 3．A．procedure B．alternative C．variation D．recipe 4．A．opportunity B．obligation C．capacity D．intention 5．A．changeable B．noticeable C．complicated D．practical 6．A．appealed to B．objected to C．applied to D．turned to 7．A．Then B．Therefore C．Otherwise D．Still 8．A．Pleased by B．Puzzled by C．Armed with D．Covered with 9．A．transform into B．break down C．speed up D．respond to 10．A．exclusively B．permanently C．inevitably D．eventually 11．A．resemble B．reform C．regenerate D．recycle 12．A．identical B．subject C．relevant D．unique 13．A．accessible B．diverse C．durable D．influential 14．A．fulfilling B．stimulating C．initiating D．promising 15．A．Likewise B．Furthermore C．Nevertheless D．Instead Passage 5 语法填空 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。 For some, cloning (克隆) is a problem, since it means that the awkward day 1 somebody proposes cloning people is unavoidable. For others, it will help medical researchers mass-produce animals for 2 (they) experiments. That sort of cloning is the goal of Dr Sun Qiang of the Chinese Academy of Science. In 2018, Dr Sun made headlines by 3 (raise) a crab-eating monkey. The following year, he performed 4 same trick with five crab-eaters. On January 16, 2024, he reported in Nature Communications that he has invented a better way to clone monkeys in quantity and that he has in his lab a healthy two-year-old male monkey 5 (produce) with the new method. Cloning has become 6 (popularity) since it gave the world Dolly, a sheep that, in 1996, became the first animal to be cloned from an adult with this method. But success 7 (rate) are low. For most species only, 1—3% of implants produce a surviving new-born. Even for cattle, where the odds are better, they are still only 5—20%. At the moment, the only people making money from cloning are companies that clone pets and horses. If cloning animals is to become a 8 (scientific) useful technology, then better ways of doing it have to 9 (find). “ 10 we have just obtained one healthy baby monkey from 11 implants, it’s not a bad outcome for the first trial of a new technique,” said Dr Sun. 2 原创精品资源学科网独家享有版权，侵权必究！ 10 / 22 学科网（北京）股份有限公司 $ 热点话题04 科学家从皮肤细胞中培育出人类卵细胞——生物科学技术 目录 时文精读------------------------------------------------------------精选外刊原创阅读理解 【原创·阅读理解】 【课标词汇积累】 【课标词汇训练】 【参考译文】 好题精练----------------------------------------------------------精选名校及联考话题专练 【阅读理解】 【阅读7选5】 【完形填空】 【语法填空】 时文精读 读 【话题·导语】 科学家从皮肤细胞中培育出人类卵细胞。 【原文·时文阅读】 文章来源：https://www.sciencenews.org/article/human-egg-cells-from-skin-cells A technique used in cloning combined with fertilization and a bit of chemical coaxing caused human skin cells to produce eggs able to give rise to early human embryos, researchers report September 30 in Nature Communications. The effort is the latest attempt to make eggs and sperm from human cells. Researchers have already succeeded in making these important cell types from many types of animals, including pandas. But producing human eggs and sperm has proven elusive. 窗体底端 Such technology may one day treat infertility for women who no longer have eggs because of age, early menopause or previous cancer treatments. Same-sex male couples may also be able to use the technique “to have, potentially, a child that’s genetically related to both partners,” says reproductive endocrinologist Paula Amato of Oregon Health & Science University in Portland. For now, the technique “is too inefficient and high risk to apply immediately to clinical application,” says stem cell researcher Katsuhiko Hayashi of the University of Osaka in Japan. Hayashi was not involved with this effort but previously reprogrammed tail cells from two adult male mice into eggs and sperm. Those reprogrammed cells gave rise to healthy mice that had two biological fathers and were able to have offspring of their own. A version of the new technique also works in mice, Amato says. “Usually, things that we can get to work in mice eventually work in humans.” At least, in making stem cells it does. Amato and colleagues removed the nucleus（细胞核） from a human egg cell and replaced it with the nucleus of a type of skin cell called a fibroblast（细胞核移植技术）. That step, called somatic cell nuclear transfer, is the same first step used in cloning Dolly the Sheep and many other species.   But the researchers weren’t trying to make a human clone. They wanted to make an egg cell, which has 23 chromosomes（染色体）. That’s half the number of chromosomes as most other cells in the body, which carry a set of 23 chromosomes inherited from the mother and 23 from the father. Cells that will give rise to eggs and sperm go through a type of cell division called meiosis（减数分裂）, which halves the number of chromosomes. In that process, each chromosome pairs with its counterpart from the other parent and swaps some DNA. The cell then divides, pulling one half of each pair into daughter cells. Then, when eggs and sperm get together, they produce a zygote（受精卵） with 46 chromosomes that will divide and make every cell in the body. But the cloned egg already had 46 chromosomes. With mice, Amato and colleagues just fertilized the cloned egg with sperm. That caused the egg to jettison half its chromosomes, producing an embryo with the correct number of chromosomes. The human eggs, though, didn’t extrude half their chromosomes when fertilized. So the researchers had to add chemical persuasion in the form of a molecule called roscovitine. That molecule allowed the winnowing of chromosomes to begin.   Some of the fertilized eggs made early human embryos, but many did not. “That’s probably, we think, because they had an abnormal number of chromosomes,” Amato says. These failed would-be eggs kicked out half their chromosomes, on average, but not the right half. None of the embryos were allowed to develop beyond the blastocyst（胚囊） stage, growing for about six days. Many stopped developing at earlier stages. None of the embryos ended up with the correct sets of chromosomes so ultimately were not viable. For instance, one embryo had 48 chromosomes instead of 46. That embryo had all 23 chromosomes from the sperm, but a mishmash of 25 chromosomes from the skin cell. Some chromosomes were present in a single copy, while others had two copies, and other chromosomes were missing entirely. The unequal divisions probably resulted because the chromosomes paired randomly instead of with their specific mate as they would in normal meiosis, Amato says. “It was not the outcome we wanted, really, but it was more proof-of-concept. ‘Hey, we can kind of make this process happen now,’” Amato says. The team is working to get the chromosomes to divvy up properly but she estimates at least a decade before the technique could be tested in clinical trials. Even then, such trials would probably not take place in the United States, which prohibits genetic modification of human embryos, she says. The new technique has a drawback in that it requires donor egg cells for the cloning step, Hayashi says. Reprogramming as he and colleagues have done does not need egg cells to make other egg cells. Still, he says, “this technology has made a significant breakthrough in halving the human genome.” He predicts “new technologies will stem from this achievement.”  【原创·阅读理解】 1.What does the underlined word in the second paragraph mean? A.difficult to find B.successful to solve C.fail to do D.easy to make A词义猜测题。根据文章第二段中的 Researchers have already succeeded in making these important cell types from many types of animals, including pandas. But研究人员已成功从多种动物（包括大熊猫）中培育出这些重要细胞类型。但是……，根据句中的but可知，后面的事情，应该是难以做到的，完成是有困难的。故选A。 2.What was the possible reason why did Amato’s experiment fail? A.Because the American government didn’t support the research. B.Because the fertilized eggs had an abnormal number of chromosomes. C.Because his team didn’t collect enough money for the experiment. D.Because his team didn’t have theory to support the experiment. B考查细节理解题。根据文章中的Some of the fertilized eggs made early human embryos, but many did not. “That’s probably, we think, because they had an abnormal number of chromosomes,” Amato says.部分受精卵发育为早期人类胚胎，但多数未能成功。“我们认为这很可能源于染色体数目异常，”阿马托解释道。故选B。 3.Which is correct according to text? A.Hayashi thinks that the new technique is useless. B.Making egg cells from skin cells from many types of animals is successful. C.Hayashi is a member of the Amato’s experiment. D.Amato predicts ten years before the technique could be tested in clinical trials. B细节理解题。根据文章第二段中的The effort is the latest attempt to make eggs and sperm from human cells. Researchers have already succeeded in making these important cell types from many types of animals, including pandas. 这项研究是利用人类细胞制造卵子和精子的最新尝试。研究人员已经成功地从包括大熊猫在内的多种动物中制造出这些重要的细胞类型。故选B。 4.What is Amato’s attitude to the technique? A.confident B.skeptical C.negative D.indifferent A考查推理判断题。根据文章中的“It was not the outcome we wanted, really, but it was more proof-of-concept. ‘Hey, we can kind of make this process happen now,’” Amato says.The team is working to get the chromosomes to divvy up properly but she estimates at least a decade before the technique could be tested in clinical trials."虽未达预期目标，但验证了技术可行性，"阿马托表示。团队正着力解决染色体精准分配难题，预计至少需十年才可能开展临床试验。可知，Amato对这个科学实验是有信心的。故选A。 【课标词汇积累】 1.technique n.技术, 技能 The teacher demonstrated a new memorization technique by using colorful mind maps to help students remember historical events more effectively. 老师展示了一种新的记忆技巧，通过使用彩色思维导图帮助学生更有效地记住历史事件。 2.combine v.使结合，混合, 联合, （使）联合；（使）合并n.联盟，集团 The science project required us to combine different chemicals to observe the reactions, which was both exciting and educational. 科学项目要求我们将不同的化学物质混合以观察反应，这既有趣又有教育意义。 3.previously adv.事先, 以前, 仓促 Previously, our school library only had a few outdated books, but now it's filled with new novels and reference materials.以前，我们学校图书馆只有几本过时的书，但现在堆满了新小说和参考资料。 4.attempt v. 努力，尝试，企图 n. 努力，尝试，（杀人）企图 Our class will attempt to organize a charity bake sale to raise funds for the local animal shelter. 我们班将尝试组织一场慈善烘焙义卖，为当地动物收容所筹集资金。 5.potentially adv. 潜在地；可能地 Staying up late to play video games can potentially affect your concentration in class the next day. 熬夜玩电子游戏可能会影响你第二天的课堂注意力。 6. reprogramme v. 再次（重新）设定程序 After failing the midterm, I decided to reprogramme my study habits by creating a strict schedule and sticking to it.期中考试不及格后，我决定重新调整学习习惯，制定严格的时间表并坚持执行。 7.modification n. 修改，修正，变更，改良，改进 The school cafeteria made a healthy modification to its menu by replacing fried foods with grilled options. 学校食堂对菜单做了健康调整，用烤制食品替代了油炸食品。 8.randomly adv. 随便地，未加计划地 The principal would randomly visit classrooms to check if students were focused during lessons. 校长会随机抽查教室，看学生上课是否专注。 9.abnormal adj. 不正常的，异常的；畸形的 It was abnormal for the usually punctual student to be late three days in a row, so the teacher asked if everything was okay.一向守时的学生连续三天迟到很不寻常，所以老师询问是否一切正常。 10.persuasion n. 劝说，说服（力）；信仰 The student council used creative persuasion tactics like free snacks to encourage more students to attend the after-school lecture.学生会用免费零食等创意劝说策略鼓励更多学生参加课后讲座。 【课标词汇训练】 根据语境，从上面的“课标词汇”中选用合适的单词及其正确形式将句子补充完整。 1.The basketball coach taught us a special shooting _____________ that improved our accuracy during practice.篮球教练教了我们一种特殊的投篮技巧，在训练中提高了我们的命中率。 2.We decided _____________ our ideas for the school festival and create a unique performance that included both dance and drama.我们决定将校园节的想法结合起来，创作一个包含舞蹈和戏剧的独特表演。 3.I had _____________ struggled with math, but after extra tutoring sessions, my grades improved significantly.我之前数学很差，但在额外辅导课后，成绩显著提高了。 4.During the sports meet, John made a brave _____________ to break the school's long jump record, landing just a few centimeters short.运动会上，约翰勇敢尝试打破学校的跳远纪录，只差几厘米就成功了。 5.Joining the debate club could _____________ help shy students build confidence in public speaking.参加辩论社可能帮助害羞的学生建立公开演讲的信心。 6.The computer teacher showed us how _____________ the robot to complete an obstacle course instead of just moving in straight lines.计算机老师教我们如何重新编程机器人，让它完成障碍路线而不仅是直线移动。 7.Our English teacher suggested some _____________ to our essay outlines to make our arguments clearer.英语老师对我们的作文提纲提出了一些修改建议，使论点更清晰。 8.For the group project, our teacher _____________ assigned teammates to ensure everyone worked with different classmates.分组作业时，老师随机分配组员以确保每个人和不同的同学合作。 9.The _____________ heat wave in October forced our school to cancel outdoor PE classes for safety reasons.十月的异常热浪迫使学校出于安全取消户外体育课。 10.After much _____________ from the art teacher, the shy student finally agreed to display her paintings in the school exhibition.经过美术老师的多次劝说，害羞的学生终于同意在学校展览中展示她的画作。 Keys: 1.technique 2.to combine 3.previously 4.attempt 5.potentially 6.to reprogramme 7.modifications 8.randomly 9.abnormal 10.persuasion 【参考译文】 研究人员在9月30日的《自然-通讯》中报告称，通过结合克隆技术与体外受精，并辅以化学诱导手段，成功使人类皮肤细胞产生能够发育为早期人类胚胎的卵细胞。 该研究是人类细胞制造卵子和精子技术的最新突破。此前科学家已从包括大熊猫在内的多种动物细胞中培育出配子，但人类配子的制备始终面临挑战。 这项技术未来或可帮助因年龄、早发性绝经或癌症治疗而卵子枯竭的女性解决不孕问题。"同性男性伴侣也可能通过该技术获得与双方均有遗传关联的后代，"波特兰俄勒冈健康与科学大学的生殖内分泌学家保拉·阿马托表示。 但大阪大学干细胞研究者林克彦指出，当前技术"效率过低且风险过高，无法立即投入临床应用"。林克彦虽未参与本研究，但曾将成年雄性小鼠尾部细胞重编程为卵子和精子，并成功培育出拥有双父系基因的健康小鼠后代。 阿马托团队采用体细胞核移植技术——即克隆多利羊的技术路径——将皮肤成纤维细胞的细胞核植入去核人类卵细胞。与克隆不同，研究者旨在制造仅含23条染色体的卵细胞。正常配子形成需经历减数分裂，使染色体数量减半并完成基因重组。但克隆卵细胞初始携带46条染色体，小鼠实验中直接受精即可触发染色体减半，而人类卵细胞需依赖化学药物罗可维汀诱导。 实验显示，部分受精卵可发育至囊胚阶段（约6天），但因染色体分配异常均未存活。典型失败案例中，一个胚胎含有精子提供的完整23条染色体，却混杂了皮肤细胞来源的25条染色体，呈现单拷贝、双拷贝甚至完全缺失的混乱状态。阿马托解释，这种异常源于染色体随机配对而非正常减数分裂的特异性配对。 "虽未达预期目标，但验证了技术可行性，"阿马托表示。团队正着力解决染色体精准分配难题，预计至少需十年才可能开展临床试验。鉴于美国禁止人类胚胎基因编辑，相关试验或将在其他地区进行。 林克彦指出该技术仍需捐赠卵细胞作为核移植载体，不如其团队开发的直接重编程方案便捷。但他承认："这项研究在人类基因组减半技术上取得重大突破，必将催生更多衍生技术。" 好题精练 练 Passage1阅读理解 Known for its role in Game of Thrones (《权力的游戏》), the dire wolf (冰原狼) went extinct over 10,000 years ago. On April 7, the US company Colossal Biosciences announced restoring this species via de-extinction — a historic first. Time magazine said scientists studied fossils (化石) such as a 13,000-year-old dire wolf tooth and a 72,000-year-old ear bone and compared their genes to those of gray wolves to discover differences. They edited 14 key genes in gray wolf blood cells to match dire wolf traits, implanting modified cell’s nuclei (核) into surrogate (代孕) dogs’ eggs. The babies, larger than gray wolves, now live in a preserve. They behaved like wolves by howling at two weeks old. But “we have not seen them attempt to hunt live prey”, Colossal’s Paige McNickle told Time magazine. Some scientists have criticized the project. Professor Nic Rawlence from Otago University questioned using fossil DNA, calling it too damaged to use. “Ancient DNA is like if you put fresh DNA in a 500 degree oven overnight, it comes out like dust,” Rawlence told the BBC． He argued Colossal actually only created “a hybrid (杂交品种)” — a gray wolf with dire wolf features. Colossal isn’t just reviving the dire wolf. Their list includes the woolly mammoth, dodo and Tasmanian tiger. Their mission goes beyond de-extinction: they also use the same technique to prevent species in danger from disappearing. For example, they brought back four red wolves, an endangered species, in the same way of restoring the dire wolf. The Center for Biological Diversity predicts that 30% of the planet’s genetic diversity could be lost by 2050. Colossal CEO Ben Lamm argues that genetic engineering is crucial to prevent this loss. Yet some warn there could be consequences. Introducing new species can cause invasive species, while cloning often leads to health problems in animals and surrogates. 1．How did scientists try to restore the dire wolves? A．By obtaining DNA from living dire wolves. B．By hybridizing different modern wolf species. C．By studying fossils of dire wolf and surrogating. D．By using complete DNA of dire wolves to clone. 2．What can be learned about the “restored” dire wolf babies? A．They exhibit some wolf-like behaviors. B．They have already begun hunting live prey. C．They are bigger in size than adult gray wolves. D．They are completely the same as the ancient dire wolves. 3．Why does the author mention red wolves in the 5th paragraph? A．To illustrate the variety of revived species. B．To highlight the importance of biodiversity. C．To contrast with the dire wolf’s revival process. D．To show Colossal’s broader conservation efforts. 4．What is the author’s attitude towards the de-extinction? A．Opposed and critical. B．Objective and cautious. C．Supportive and optimistic. D．Humorous and unconcerned. 【答案】1．C 2．A 3．D 4．B 【解析】本文是一篇新闻报道。文章主要报道了美国公司Colossal Biosciences通过基因编辑技术尝试复活已灭绝的冰原狼，以及该技术面临的争议和更广泛的应用。 1．细节理解题。根据第二段中“Time magazine said scientists studied fossils (化石) such as a 13,000-year-old dire wolf tooth and a 72,000-year-old ear bone and compared their genes to those of gray wolves to discover differences. They edited 14 key genes in gray wolf blood cells to match dire wolf traits, implanting modified cell’s nuclei into surrogate dogs’ eggs. (据《时代》杂志报道，科学家们研究了化石，比如一颗1.3万年前的冰原狼牙齿和一块7.2万年前的耳骨，并将它们的基因与灰狼的基因进行比较，以发现差异。他们编辑了灰狼血细胞中的14个关键基因，使其与冰原狼的特征相匹配，将修改后的细胞核植入代孕狗的卵子中)”可知，科学家们是通过研究冰原狼的化石，编辑灰狼血细胞中的关键基因，并将其植入代孕狗的卵子中，来尝试恢复冰原狼的。故选C。 2．细节理解题。根据第三段中“The babies, larger than gray wolves, now live in a preserve. They behaved like wolves by howling at two weeks old.(这些幼崽比灰狼大，现在生活在一个保护区里。它们在两周大的时候就像狼一样嚎叫)”可知，这些“复活”的冰原狼幼崽表现出了一些类似狼的行为。故选A。 3．推理判断题。根据第五段中“Colossal isn’t just reviving the dire wolf. Their list includes the woolly mammoth, dodo and Tasmanian tiger. Their mission goes beyond de-extinction: they also use the same technique to prevent species in danger from disappearing. For example, they brought back four red wolves, an endangered species, in the same way of restoring the dire wolf.(Colossal公司不仅仅是在复活冰原狼。它们的名单还包括猛犸象、渡渡鸟和塔斯马尼亚虎。它们的使命不仅仅是让灭绝的物种复活：它们还使用同样的技术来防止濒危物种消失。例如，他们用同样的方法带回了四种濒危物种红狼，就像恢复冰原狼一样)”可推知，作者提到红狼是为了展示Colossal公司在保护濒危物种方面的更广泛努力。故选D。 4．推理判断题。根据第一段中“On April 7, the US company Colossal Biosciences announced restoring this species via de-extinction — a historic first.(4月7日，美国Colossal Biosciences公司宣布通过“去灭绝”技术恢复这一物种，这是历史上的首次)”以及最后一段中“Colossal CEO Ben Lamm argues that genetic engineering is crucial to prevent this loss. Yet some warn there could be consequences. Introducing new species can cause invasive species, while cloning often leads to health problems in animals and surrogates.(Colossal公司首席执行官本•拉姆认为，基因工程对于防止这种损失至关重要。然而，也有人警告说可能会有后果。引入新物种可能会导致入侵物种，而克隆往往会导致动物和代孕者的健康问题)”可推知，作者在文章中既提到了Colossal公司的创新尝试，也提到了科学界的争议和潜在风险，因此作者对于去灭绝技术的态度是客观且谨慎的。故选B。 【词汇积累】 1.extinct adj. 灭绝的；废除了的 2.historic adj. 历史（性）的；有历史记载的 3.implant vt. 移植；灌输；植入，插入vi. （受精卵）着床；被移植 4.preserve v. 保持；保护；保险；腌制n. 蜜饯；果酱；腌菜 5.criticize v. 批评，指责；评价，批判 6.endangered adj. （动物、鸟类等）濒危的，濒于灭绝的 7.diversity n. 多样性，多元性；差异，不同 8.crucial adj. 至关重要的，关键性的 Passage2阅读理解 An ambitious plan to genetically engineer a version of the woolly mammoth (长毛猛犸象), a giant that disappeared 4,000 years ago, is making some progress. A new biosciences and genetics company, Colosal, has raised $15 million to create a mammoth hybeid that looks exactly like its extinct counterpart. The goal isn’t to clone a mammoth, but to create, through genetic engineering, a living, walking elephant-mammoth hybeid. The scientists revealed they had reprogrammed cells from an Asian elephant, the woolly mammoth’s closest living relative. These changed cells can grow into any kind of elephant cell. The research team has analyzed the than 50 changes to the genetic code of the Asian elephant to give it the characteristics it needs to survive and thrive in the Arctic. These characteristics include a 10-centimeter layer of insulating (绝缘的) fat, five different kinds of hair including some that is up to a meter long, and smaller ears that will help the hybrid tolerate the cold. Colossal believes that bringing the woolly mammoth back to life could possibly help restore the fragile Arctic tundra (冻原) ecosystem, which is at risk as the world warms. The company has claimed that mammoths, if they should return to their natural habitat in the Arctic in sufficient numbers, would help slow down frozen soil melting. Some scientists believe that, before their extinction, animals such as mammoths and horses kept the earth frozen underneath by walking on the grass, knocking down trees and pressing snow tight. One small study in Siberia published in 2021 suggested that the presence of large mammals such as horses and reindeer resulted in lower soil temperatures in the protected area where they were kept compared with land outside that area. Colossal also announced plans to being some other animals back to life such as the Tasmanian tiger in 2023 and the dodo in 2024, but its work on the mammoth has been going on longest. 5．What does the underlined word “counterpart” in the first paragraph refer to? A．Endangered animal. B．Fellow species. C．Cloned elephant. D．Extracted cell. 6．What can we learn about the hybrid? A．It is visually similar to the Asian elephant. B．It can grow into any types of elephant cell. C．Thick fat and smaller ears help it endure the severe weather. D．Long hair like a woolly coat keeps it from the cold and attacks. 7．Why does the author mention the study in Siberia in Paragraph 3? A．To illustrate the possibility of reintroducing mammoths to their natural habitats. B．To compare different kinds of nature reserves where large mammals were kept. C．To indicate the link between the extinction of large mammals and climate change. D．To show the potential impact of returning mammoths to the Arctic on the ecosystem. 8．What can we infer from the last paragraph? A．The project on bringing back the mammoth costs the most. B．The Tasmania tiger and the dodo are also long-dead animals. C．Colossal needs increased investment to advance the projects. D．Colossal is completely confident in its technology and scientists. 【答案】5．B 6．C 7．D 8．B 【解析】本文是一篇说明文。文章主要讲述了一家生物科技公司成功创造了猛犸象近亲亚洲象的干细胞，为复活猛犸象迈出重要一步，引发环保和科学界的讨论。 5．词句猜测题。根据第一段中“A new biosciences and genetics company, Colosal, has raised $15 million to create a mammoth hybeid that looks exactly like its extinct counterpart. The goal isn’t to clone a mammoth, but to create, through genetic engineering, a living, walking elephant-mammoth hybeid. (一家名为Colosal的新型生物科学和遗传学公司已筹集到1500万美元，用于创造一种看起来与其灭绝的counterpart一模一样的猛犸象杂交品种。目标不是克隆猛犸象，而是通过基因工程创造一种活生生的、行走的大象-猛犸象杂交品种)”可知，此处指灭绝的猛犸象，counterpart意为“相对应的人或物”，所以此处指与现在的杂交品种相对应的物种，即“灭绝的猛犸象”，相当于“同类物种”。A. Endangered animal濒危动物；B. Fellow species同类生物；C. Cloned elephant克隆大象；D Extracted cell提取的细胞。故选B。 6．细节理解题。根据第二段中“These changed cells can grow into any kind of elephant cell. The research team has analyzed the than 50 changes to the genetic code of the Asian elephant to give it the characteristics it needs to survive and thrive in the Arctic. These characteristics include a 10-centimeter layer of insulating (绝缘的) fat, five different kinds of hair including some that is up to a meter long, and smaller ears that will help the hybrid tolerate the cold. (这些改变的细胞可以生长成任何种类的大象细胞。研究小组分析了亚洲象基因组的50多处变化，使其具有在北极生存和繁衍所需的特征。这些特征包括一层10厘米厚的绝缘脂肪、五种不同的毛发 (其中一些长达一米) 以及较小的耳朵，这将帮助杂交品种抵御寒冷)”可知，杂交品种有10厘米厚的绝缘脂肪和较小的耳朵，这些可以帮助杂交品种忍受恶劣的天气。故选C。 7．推理判断题。根据第三段中“One small study in Siberia published in 2021 suggested that the presence of large mammals such as horses and reindeer resulted in lower soil temperatures in the protected area where they were kept compared with land outside that area. (2021年在西伯利亚进行的一项小型研究表明，在保护区内饲养的马和驯鹿等大型哺乳动物的存在，使得该区域的土壤温度比保护区外的土地更低)”可知，提到这项研究是为了说明猛犸象回归北极可能对生态系统产生的潜在影响，例如降低土壤温度、保护冻土层等。故选D。 8．推理判断题。根据最后一段“Colossal also announced plans to bring some other animals back to life such as the Tasmanian tiger in 2023 and the dodo in 2024, but its work on the mammoth has been going on longest. (Colossal公司还宣布计划于2023年复活塔斯马尼亚虎，于2024年复活渡渡鸟，不过其关于猛犸象的研究开展得最早)”可推知，塔斯马尼亚虎和渡渡鸟也是早已灭绝的动物。故选B。 【长难句分析】 【文章原句】Colossal believes that bringing the woolly mammoth back to life could possibly help restore the fragile Arctic tundra (冻原) ecosystem, which is at risk as the world warms. 【句式分析】 这个句子是一个复合句。That后是宾语从句，which is at risk as the world warms是宾语从句中的非限制性定语从句。 【翻译】Colossal认为，让猛犸象复活可能有助于恢复脆弱的北极苔原生态系统，随着全球变暖，这个生态系统正面临风险。 Passage 3 阅读七选五 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。 Four Rules for Successful Plant Cloning Plant growers have two choices when it comes to starting new plants: growing from seed, or plant cloning. And plant clones offer advantages that growing plants from seed can’t offer. 1 , and as long as you do the cloning yourself, you know who the mother plant is and how your clones will grow, yield, and get you high. But it’s an art and science to plant cloning. Take your plant cuttings from a healthy motherplant. Plant cloning gives you genetic copies of your motherplant. 2 , your clones get the best start possibly. Avoid using motherplants that are sick, or that are plagued with pests. 3 . Most plant clones prefer temperatures slightly higher than your ideal grow room temperature, and they don’t like a day and night cycle with a temperature drop at night. That’s why most growers root their cuttings under lighting that stays on 24 hours a day. The lighting itself creates temperature stabilization. Temperatures between 74-77 degrees F are the range you want. Clones like high humidity(湿度). Your cuttings need a humid environment in the 75-95% humidity range until they’ve created roots and are able to intake water through them. That’s why many plant cloners use humidity covers. 5 , they’ll die. Use sterile(无菌的) equipment and materials. You already figured out that your scissors, knife, or other tools for cutting clones has to be clean. But you also want to make sure you trays, cloning covers, and root zone media are clean and sterile too. Don’t reuse cloning cubes or cloning powders and gels. 5 . When you follow these plant cloning tips, your clone success rate should be nearly 100%. A．Start fresh every time B．Use kind LED lighting C．Give your plant clones consistent climate D．Growing from clones you’re sure to have all females E．If you’re taking 20 clones and seeing only 10 of them survive F．Until your clones have functioning roots, if they’re in dry air G．If your motherplants are strong, healthy, and have potent genetics 【答案】1．D 2．G 3．C 4．F 5．A 【解析】本文是一篇说明文，主要介绍了成功克隆植物的四个原则。 1．承接句。根据后文中and as long as you do the cloning yourself, you know who the mother plant is and how your clones will grow, yield, and get you high可知，此处说明克隆植物的好处，得到的都是雌株。故选D。 2．承接句。根据主题句中的关键词motherplant以及后一句your clones get the best start possibly.可知，本空说明要挑选强壮、健康，有强大的遗传力的母本植株。故选G。 3．主题句。根据段中关键词temperatures可知，本段说明克隆植物所需的温度。故选C。 4．总结句。选项中的dry air与主题句中的humidity相对应。故选F。 5．总结句。本句与主题句和前文Don’t reuse cloning cubes or cloning powders and gels.相呼应，说明克隆植物时要用无菌的工具，最好是新的工具。故选A。 Passage 4 完形填空 Like anything built by evolution, the human body has many downsides, teeth without exception. Adult humans only get one set of teeth, which must last about 60 years. However, a(n) 1 of poverty, sugar-rich diets and poor hygiene means 2.5bn people globally suffer from tooth decay, in which acid produced by mouth-living bacteria eats away the hard enamel (牙釉质) that 2 the outside of a tooth, leading to further infection and damage. Once decay has set in, all a dentist can do is to fill the gap with artificial filling. But in a paper published in Cell, Hannele Ruohola-Baker, a stem-cell biologist at the University of Washington, and her colleagues offer a possible 3 . Stem cells have the 4 to turn themselves into any other type of cell in the body. It may soon be possible, the researchers claim, to use those 5 cells to regrow a tooth’s enamel naturally. The first step was to work out how enamel is produced. As enamel-making cells, known as ameloblasts, disappear soon after a person’s adult teeth have finished growing, the researchers 6 samples of tissue from human foetuses (胚胎), which contain plenty of functioning ameloblasts. 7 , they checked to see which genes were especially active in the enamel-producing cells. It turned out that genes designed to bind to calcium were particularly busy. 8 that information, Dr Ruohola-Baker and her colleagues next checked to see whether the stem cells could be persuaded to 9 ameloblasts. The team devised various drugs designed to activate the genes expressed in functioning ameloblasts. That worked, with the engineered ameloblasts producing the same proteins as the natural sort. For now, the work is more concept than a medical treatment. The next step is to boost enamel production further, with a view to 10 beginning clinical trials. The hope is that, one day, medical versions of the team’s findings could be used as biological implants, to 11 a patient’s decayed teeth. Stem-cell-based therapies are not the only ones heading to clinical trials. Another treatment, known as biomimetic repair, involves rebuilding the tooth crown using synthetic (人工合成的) proteins, which are similar, but not quite 12 , to human enamel. The proteins could be included in toothpaste and even cough drops. But synthetic formulations can be less 13 than human enamel. It will take time for either technology to become reality. One question is how durable the enamel made by stem-cell-derived ameloblasts is. Another is how best to deliver the stem cells to a patient’s mouth. But these findings are 14 . As any dentist will tell you, prevention is better than cure. 15 , a better cure would be always welcome. There is no doubt that this research offers a new prospect for future dental care. 1．A．combination B．absence C．application D．coincidence 2．A．contains B．coats C．floats D．fills 3．A．procedure B．alternative C．variation D．recipe 4．A．opportunity B．obligation C．capacity D．intention 5．A．changeable B．noticeable C．complicated D．practical 6．A．appealed to B．objected to C．applied to D．turned to 7．A．Then B．Therefore C．Otherwise D．Still 8．A．Pleased by B．Puzzled by C．Armed with D．Covered with 9．A．transform into B．break down C．speed up D．respond to 10．A．exclusively B．permanently C．inevitably D．eventually 11．A．resemble B．reform C．regenerate D．recycle 12．A．identical B．subject C．relevant D．unique 13．A．accessible B．diverse C．durable D．influential 14．A．fulfilling B．stimulating C．initiating D．promising 15．A．Likewise B．Furthermore C．Nevertheless D．Instead 【答案】 1．A 2．B 3．B 4．C 5．A 6．D 7．A 8．C 9．A 10．D 11．C 12．A 13．C 14．D 15．C 【解析】这是一篇说明文。文章主要介绍了科学家对于干细胞转化成成釉细胞的研究过程和意义。 1．考查名词词义辨析。句意：然而，由于贫困、高糖饮食和卫生条件差，全球有25亿人患有蛀牙，口腔细菌产生的酸会侵蚀覆盖在牙齿外部的硬牙釉质，导致进一步的感染和损伤。A. combination组合；B. absence缺席；C. application应用；D. coincidence巧合。根据后文的“of poverty, sugar-rich diets and poor hygiene”可知，贫困、高糖饮食和卫生条件差的结合，导致了人患有蛀牙。故选A项。 2．考查动词词义辨析。句意：然而，由于贫困、高糖饮食和卫生条件差，全球有25亿人患有蛀牙，口腔细菌产生的酸会侵蚀覆盖在牙齿外部的硬牙釉质，导致进一步的感染和损伤。A. contains包含；B. coats覆盖；C. floats漂浮；D. fills填充。空前的that引导限定性定语从句，先行词是enamel。根据后文的“the outside of a tooth”结合常识可知，牙釉质覆盖在牙齿外部。故选B项。 3．考查名词词义辨析。句意：但是在《细胞》杂志上发表的一篇论文中，华盛顿大学的干细胞生物学家Hannele Ruohola-Baker和她的同事提供了一种可能的替代方法。A. procedure程序；B. alternative备选方案；C. variation变异；D. recipe配方。根据前文的“Once decay has set in, all a dentist can do is to fill the gap with artificial filling.”和后文的“Stem cells have the 4 to turn themselves into any other type of cell in the body. It may soon be possible, the researchers claim, to use those 5 cells to regrow a tooth’s enamel naturally.”可知，利用干细胞自然地再生牙齿的牙釉质是对前文用人工填充物填补空隙的替代方法。故选B项。 4．考查名词词义辨析。句意：干细胞有能力将自己转化为体内任何其他类型的细胞。A. opportunity机会；B. obligation机会；C. capacity能力；D. intention打算。根据后文的“to turn themselves into any other type of cell in the body. It may soon be possible, the researchers claim, to use those5 cells to regrow a tooth’s enamel naturally.”可知，干细胞有能力将自己转化为体内任何其他类型的细胞。故选C项。 5．考查形容词词义辨析。句意：研究人员声称，利用这些可变化的细胞自然地再生牙齿的牙釉质可能很快就会成为可能。A. changeable可变的；B. noticeable引人注目的；C. complicated复杂的；D. practical实际的。根据前文的“Stem cells have the 4 to turn themselves into any other type of cell in the body.”可知，干细胞是可变化的。故选A项。 6．考查动词短语辨析。句意：由于牙釉质生成细胞，即成釉细胞，在人的成年牙齿完成生长后很快就会消失，研究人员转向了人类胎儿的组织样本，其中含有大量的功能成釉细胞。A. appealed to呼吁；B. objected to反对；C. applied to应用于；D. turned to转向。根据前文的“As enamel-making cells, known as ameloblasts, disappear soon after a person’s adult teeth have finished growing”和后文“samples of tissue from human foetuses (胚胎), which contain plenty of functioning ameloblasts.”可知，成釉细胞在成年人的身体里没有，故研究人员转向了人类胎儿的组织样本。故选D项。 7．考查副词词义辨析。句意：然后，他们检查哪些基因在产生牙釉质的细胞中特别活跃。A. Then然后；B. Therefore因此；C. Otherwise否则；D. Still还。根据前文的“the researchers 6 samples of tissue from human foetuses (胚胎), which contain plenty of functioning ameloblasts.”可知，研究人员转向对人类胎儿的组织样本的研究，然后就进行了具体的研究。故选A项。 8．考查动词短语辨析。句意：有了这些信息，Ruohola-Baker博士和她的同事们接下来检查了干细胞是否可以转化成成釉细胞。A. Pleased by对……感到高兴；B. Puzzled by对……感到困惑；C. Armed with 拥有；D. Covered with被……覆盖。根据前文的“they checked to see which genes were especially active in the enamel-producing cells. It turned out that genes designed to bind to calcium were particularly busy.”可知，他们找到了特别活跃的产生牙釉质的细胞，因此有了这些信息，Ruohola-Baker博士和她的同事们开始展开进一步的研究。故选C项。 9．考查动词短语辨析。句意：有了这些信息，Ruohola-Baker博士和她的同事们接下来检查了干细胞是否可以转化成成釉细胞。A. transform into转化为；B. break down分解；C. speed up加速；D. respond to回应。根据前文的“the stem cells could be persuaded to”和后文“ameloblasts”可知，研究人员想把干细胞转化成成釉细胞。故选A项。 10．考查副词词义辨析。句意：下一步是进一步促进牙釉质的产生，以期最终开始临床试验。A. exclusively唯一地；B. permanently永久地；C. inevitably不可避免地；D. eventually最后。根据后文的“beginning clinical trials”可知，开始临床试验是研究的最终目标。故选D项。 11．考查动词词义辨析。句意：希望有一天，该团队的研究成果的医学版本可以用作生物植入物，以再生患者的蛀牙。A. resemble类似于；B. reform改革；C. regenerate再生；D. recycle回收利用。根据后文的“a patient’s decayed teeth.”可知，使患者的蛀牙再生是研究的目的。故选C项。 12．考查形容词词义辨析。句意：另一种被称为仿生修复的治疗方法是使用合成蛋白质重建牙冠，这种蛋白质与人类牙釉质相似，但并不完全相同。A. identical相同的；B. subject服从于；C. relevant相关的；D. unique唯一的。根据前文的“which are similar, but not”可知，二者相似，但并不完全相同。故选A项。 13．考查形容词词义辨析。句意：但合成配方可能不如人类牙釉质耐用。A. accessible可接近的；B. diverse多样的；C. durable耐用的；D. influential有很大影响的。根据前文的“Another treatment, known as biomimetic repair, involves rebuilding the tooth crown using synthetic (人工合成的) proteins, which are similar, but not quite 12, to human enamel.”、“But synthetic formulations can be less”和后文“than human enamel”可知，这种合成蛋白质与人类牙釉质相似，但并不完全相同，可能不如人类牙釉质耐用。故选C项。 14．考查动词词义辨析。句意：但这些发现是有希望的。A. fulfilling实现；B. stimulating刺激；C. initiating开始；D. promising承诺。根据前文的“It will take time for either technology to become reality.”可知，这两种技术都需要时间才能成为现实，但这些发现是有希望的。故选D项。 15．考查副词词义辨析。句意：然而，更好的治疗方法总是受欢迎的。A. Likewise同样地；B. Furthermore此外；C. Nevertheless然而；D. Instead相反。根据前文的“As any dentist will tell you, prevention is better than cure.”和后文“a better cure would be always welcome”可知，前后句意存在转折关系。故选C项。 Passage 5 语法填空 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。 For some, cloning (克隆) is a problem, since it means that the awkward day 1 somebody proposes cloning people is unavoidable. For others, it will help medical researchers mass-produce animals for 2 (they) experiments. That sort of cloning is the goal of Dr Sun Qiang of the Chinese Academy of Science. In 2018, Dr Sun made headlines by 3 (raise) a crab-eating monkey. The following year, he performed 4 same trick with five crab-eaters. On January 16, 2024, he reported in Nature Communications that he has invented a better way to clone monkeys in quantity and that he has in his lab a healthy two-year-old male monkey 5 (produce) with the new method. Cloning has become 6 (popularity) since it gave the world Dolly, a sheep that, in 1996, became the first animal to be cloned from an adult with this method. But success 7 (rate) are low. For most species only, 1—3% of implants produce a surviving new-born. Even for cattle, where the odds are better, they are still only 5—20%. At the moment, the only people making money from cloning are companies that clone pets and horses. If cloning animals is to become a 8 (scientific) useful technology, then better ways of doing it have to 9 (find). “ 10 we have just obtained one healthy baby monkey from 11 implants, it’s not a bad outcome for the first trial of a new technique,” said Dr Sun. 【答案】 1．when 2．their 3．raising 4．the 5．produced 6．popular 7．rates 8．scientifically 9．be found 10．Although/Though/While 【解析】本文是一篇新闻报道。文章主要介绍了中科院成功培育出恒河猴的克隆技术。 1．考查定语从句。句意：对于一些人来说，克隆是一个问题，因为这意味着尴尬的一天，当有人提出克隆人是不可避免的。定语从句修饰先行词the day，关系词在从句作时间状语，故此处用关系副词 when。故填when。 2．考查代词。句意：对其他人来说，这将有助于医学研究人员为他们的实验大量生产动物。此处用形容词性物主代词their修饰后面的 experiments。故填their。 3．考查非谓语动词。句意：2018年，孙博士养了一只吃螃蟹的猴子，成为头条新闻。by为介词，故用所给动词的动名词raising作宾语。故填raising。 4．考查冠词。句意：第二年，他又和五个吃螃蟹的人表演了同样的把戏。the same意为“同一个”，为固定搭配。故填the。 5．考查非谓语动词。句意：2024年1月16日，他在《自然通讯》上报告说，他发明了一种更好的方法来大量克隆猴子，他的实验室里有一只用这种新方法生产的健康的两岁雄性猴子。produce与monkey之间存在逻辑上的动宾关系，故用过去分词作定语。故填produced。 6．考查形容词。句意：1996年，克隆羊多莉诞生，成为第一只用这种方法从成年人身上克隆出来的动物。自那以后，克隆技术开始流行起来。所填词在此处作 become的表语，故用所给名词的形容词形式。故填popular。 7．考查名词复数。句意：但成功率很低。rate为可数名词，根据空后的谓语动词are可知，此处用所给名词的复数形式。故填rates。 8．考查副词。句意：如果克隆动物要成为一项科学上有用的技术，那么就必须找到更好的方法。修饰形容词 useful，作状语，故用所给形容词的副词形式 scientifically。故填scientifically。 9．考查语态。句意：如果克隆动物要成为一项科学上有用的技术，那么就必须找到更好的方法。find 与 ways存在逻辑上的动宾关系，故用被动语态，且have to do sth.。故填be found。 10．考查连词。句意：孙博士说:“虽然我们刚刚从11次植入中获得了一只健康的小猴子，但对于一项新技术的首次试验来说，这是一个不错的结果。”引导让步状语从句，表示“虽然”用连词although，though或 while。首字母大写。故填Although/Though/While。 2 原创精品资源学科网独家享有版权，侵权必究！ 10 / 22 学科网（北京）股份有限公司 $