题型:阅读理解 题类:常考题 难易度:普通
吉林省长春外国语学校2019届高三上学期英语期末考试试卷(含小段音频)
Chinese scientists recently have produced two monkeys with the same gene, Zhong Zhong and Hua Hua, using the same technique that gave us Dolly the sheep. These monkeys are not actually the first primates(灵长类)to be cloned. Another one named Tetra was produced in the late 1990s by embryo(胚胎)splitting, the division of an early-stage embryo into two or four separate cells to make clones. By contrast, they were each made by replacing an egg cell nucleus(原子核)with DNA from a differentiated body cell. This Dolly method, known as somatic cell nuclear transfer(SCNT), can create more clones and allows researchers greater control over the edits they make to the DNA.
Success came from adopting several new techniques. These included a new type of microscopy to better view the cells during handling or using several materials that encourage cell reprogramming, which hadn't been tried before on primates. Still, the research process proved difficult, and many attempts by the team failed. Just two healthy baby monkeys born from more than 60 tested mothers. This leads to many researchers' pouring water on the idea that the team's results bring scientists closer to cloning humans. They thought this work is not a stepping stone to establishing methods for obtaining live born human clones. Instead, this clearly remains a very foolish thing to attempt, it would be far too inefficient, far too unsafe, and it is also pointless.
But the scientists involved emphasize that this is not their goal. There is now no barrier for cloning primate species, thus cloning humans is closer to reality. However, their research purpose is entirely for producing non-human primate models for human diseases; they absolutely have no intention, and society will not permit this work to be extended to humans. Despite limitations, they treat this breakthrough a novel model system for scientists studying human biology and disease.
Are You a Morning Person?
Mornings are not for everyone. Knowing that our own bodies may be wired to prefer a certain time of day is certainly a relief. But many of us still have to wake up and function during those first daylight hours. So what can you do?
We tapped a variety of experts—from sleep experts to nutritionists to life organizational pros—to share their tricks on how to make morning less stressful and more pleasant (for) even the most after-hours of night owls.
①Night waking
Poor sleep quality can explain why we sometimes wake up from eight hours of snoozing and feel like we only clocked in at four. "It's normal to have one or two awakenings, but more than that leaves us feeling groggy in the morning because of the fragmented sleep," [explains Shelby Harris, director of the behavioral sleep medicine program at Montefiore Medical Center.]
②The Science of snoozing
The snooze button does more harm than good. Nodding off again sends you into a light and fragmented sleep! Multiple snoozes can leave you feeling groggier than just getting out of bed the first time.
Instead, be honest about the time you intend to get up and then enjoy every last minute of shuteye, so you can wake up alert and ready to go.
③Don't ease into your workday
It can be tempting to plow through the easy things early on-checking e-mail, scanning the headlines—but it's wise to tackle the bigger stuff first. "Getting to work on the most important tasks not only ups the chances that they actually get done, but it also leaves you with a burst of accomplishment to take with you the rest of the day," says Jason Selk, coauthor of Organize Tomorrow Today.
④Save social media for later
Schedule a social media block later in the afternoon to check in when you're likely to need a break anyway, and save the morning for the important stuff.
Specialized Term life organizational pro(n) 生活管理达人 someone who is an expert at helping others bring balance and order into their lives |
Vocabulary Focus
tap(v) [tæp] to get or make use of something
groggy (adj) ['gragi] weak and unable to think clearly or walk correctly, usually because of tiredness or illness
shuteye (n) ['ʃʌtai] sleep
plow through (something) (phr v) to finish reading, eating or dealing with something with difficulty
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