A recent study has come up with _____ unexpected conclusion that ____ Africa elephants should be divided into two different species.
A.a, the B. an, the C. an, an D. the, the
高三英语单项填空简单题
A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species
The discovery was made by researchers at York and Harvard universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant, African forest elephant and African savanna elephant
Once they obtained DNA sequences (序列) from two fossils (化石)，mammoths and mastodons， the team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephants and the African forest elephants have been distinct species for several million years. The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists.
There has long been debate in the scientific community that the two might be separate species but this is the most convincing scientific evidence so far that they are indeed different species.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3.5metres while the forest elephant has an average shoulder height of 2.5metres. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. But the fact that they look so different does not necessarily mean they are different species. However, the proof lay in the analysis of the DNA.
Alfred Roca, assistant professor in the department of Animal Sciences at the University of Minois, said, “We now have to treat the forest and savanna elephants as two different units for conservation purpose. Since 1950 all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinct animals, the forest elephant should become a bigger priority (优先)for conservation purpose .”
1.One of the fossils studied by the researchers is that of ________.
A. the Asian elephant B. the forest elephant
C. the savanna elephant D. the mastodon elephant
2.The underlined word “divergence” in paragraph 4means “________”
A. evolution B. exhibition C. separation D. examination
3.The researcher’s conclusion was based on a study of the African elephant’s _____
A. DNA B. height C. weight D. population
4.What were Alfred Roca’s words mainly about?
A. The conservation of African elephants.
B. The purpose of studying African elephants
C. The way to divide African elephants into two units
D. The reason for the distinction of African elephants
5.Which of the following can be the best title for the passage?
A. Naturalist’s Belief about Elephants.
B. Amazing Experiment about Elephants
C. An Unexpected Finding about Elephants
D. A Long scientific Debate about Elephants
高三英语阅读理解中等难度题查看答案及解析
A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species
The discovery was made by researchers at York and Harvard universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant, African forest elephant and African savanna elephant
Once they obtained DNA sequences (序列) from two fossils (化石)，mammoths and mastodons the team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephants and the African forest elephants have been distinct species for several million years. The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists.
There has long been debate in the scientific community that the two might be separate species but this is the most convincing scientific evidence so far that they are indeed different species.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3.5metres while the forest elephant has an average shoulder height of 2.5metres. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. But the fact that they look so different does not necessarily mean they are different species. However, the proof lay in the analysis of the DNA.
Alfred Roca, assistant professor in the department of Animal Sciences at the University of Minois, said, “We now have to treat the forest and savanna elephants as two different units for conservation purpose. Since 1950 all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinct animals, the forest elephant should become a bigger priority (优先)for conservation purpose .”
1.
One of the fossils studied by the researchers is that of ________.
A. the Asian elephant B. the forest elephant
C. the savanna elephant D. the mastodon elephant
2.
The underlined word “divergence” in paragraph 4means “________”
A. evolution B. exhibition C. separation D. examination
3.
The researcher’s conclusion was based on a study of the African elephant’s ____________
A. DNA B. height C. weight D. population
4.
What were Alfred Roca’s words mainly about?
A. The conversation of African elephants.
B. The purpose of studying African elephants
C. The way to divide African elephants into two units
D. The reason for the distinction of African elephants
5.
Which of the following can be the best title for the passage?
A. Naturalist’s Belief about Elephants. B. Amazing Experiment about Elephants
C. An Unexpected Finding about Elephants D. A Long scientific Debate about Elephants
高三英语阅读理解中等难度题查看答案及解析
A recent study has come up with _____ unexpected conclusion that ____ Africa elephants should be divided into two different species.
A．a, the B．an, the C．an, an D．the, the
高三英语单项填空中等难度题查看答案及解析
A recent study has come up with _____ unexpected conclusion that ____ Africa elephants should be divided into two different species.
A.a, the B. an, the C. an, an D. the, the
高三英语单项填空简单题查看答案及解析
A recent study has ________an unexpected conclusion that the African elephant should be divided into two different species.
A．kept up with B．made up with C．caught up with D.come up with
高三英语单项填空中等难度题查看答案及解析
(2014·安徽省芜湖三校一模)A recent study has ________an unexpected conclusion that the African elephant should be divided into two different species.
A．kept up with B．made up with
C．caught up with D．come up with
高三英语单项填空简单题查看答案及解析
(2013·四川省宜宾五校二调)A recent study has ________ an unexpected conclusion that the African elephant should be divided into two different species.
A．kept up with B．made up with
C．caught up with D．come up with
高三英语单项填空简单题查看答案及解析
--Alvin, are you coming with us?
--I'd love to, but something unexpected ________.
A. has come up B. was coming up
C. had come up D. would come up
高三英语单项填空中等难度题查看答案及解析
— Alvin，are you coming with us?
—I'd love to，but something unexpected ________.
A．has come up B．was coming up
C．had come up D．would come up
高三英语单项填空中等难度题查看答案及解析
Your chair is your enemy. That is the conclusion of several recent studies. Among people who sit in front of the television for more than three hours each day, those who exercise are as fat as those who don’t.
So what’s wrong with sitting? The answer seems to have two parts. The first is that sitting is one of the most passive things you can do. Compared to sitting, standing in one place is hard work. To stand, you have to tense your leg muscles, and engage the muscles of your back and shoulders; while standing, you often shift from leg to leg. All of this burns energy.
You may think you have no choice about how much you sit. But this isn’t true. Suppose you sleep for eight hours each day, and exercise for one. That still leaves 15 hours of activities. Even if you exercise, most of the energy you burn will be burnt during these 15 hours, so weight gain is often the cumulative(累积的) effect of a series of small decisions: Do you take the stairs or the elevator? Do you walk to the corner store, or drive?
But it looks as though there’s a more sinister aspect to sitting. Some evidence suggests that when you spend long periods sitting, your body actually does things that are bad for you.
Lipoprotein lipase(蛋白脂酶) is a molecule that plays a central role in how the body processes fats. Low levels of lipoprotein lipase are associated with a variety of health problems. Studies in rats show that leg muscles only produce this molecule when they are actively being moved. The result is that when you sit, an important part of your metabolism(新陈代谢) slows down. You may also have a higher risk of suffering from diabetes(糖尿病).
Some people have advanced radical solutions to the sitting syndrome(综合症): replace your sit-down desk with a stand-up desk, or watch television in a rocking chair. But whatever you choose, know this. The data is clear; look out for your chair.
1.What would be the best title of this passage?
A．Become an Athlete to Be Healthy.
B．Choose a Better Chair for You.
C．How to Speed Up Your Metabolism.
D．Stand Up While You Read This.
2.Paragraphs 2 and 3 tell us that.
A．taking too much exercise harms people’s health
B．sitting a lot reduces the benefits of taking exercise
C．people needn’t depend on exercise to keep healthy
D．healthy people are those who sit less and stand more
3.Which of the following is the best advice on how to control our weight?
A．Exercising at least an hour a day.
B．Standing as long as possible.
C．Using our energy actively in daily life.
D．watching TV in a rocking chair.
4.The author mentions lipoprotein lipase mainly to.
A．show that it plays a big part in keeping us healthy
B．tell us that it isn’t produced while we are sitting
C．suggest that we should take less exercise to be healthy
D．prove sitting for long is bad for our body
高三英语阅读理解简单题查看答案及解析