Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis’ Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the cast sides of their stems grew more rapidly than the west sides. Ai night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day, or on the other side at night. A plant growth-regulating hormone, called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said. “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A.To see how sunflowers grow up.
B.To show what sunflowers’ genes are.
C.To study why sunflowers track the sun.
D.To check if sunflowers swing in cloudy days.
2.What does the underlined word “slaking” probably mean in Paragraph 3?
A.Tracking. B.Fastening.
C.Preserving. D.Researching.
3.What is the result of sunflowers being stopped from moving?
A.They won’t grow well.
B.They will grow faster than usual.
C.They won’t swing back though set free.
D.They will produce a number of new genes.
4.What is the advantage of sunflowers’ dance to the sun?
A.They attract more insects. B.They save more energy.
C.They mature more rapidly. D.They produce more flowers.
高三英语阅读理解困难题
Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis’ Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day, or on the other side at night. A plant growth-regulating hormone, called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said. “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A.To see how sunflowers grow up.
B.To show what sunflowers’ genes are.
C.To study why sunflowers track the sun.
D.To check if sunflowers swing in cloudy days.
2.What does the underlined word “staking”(Par 3) probably mean in ?
A.Tracking. B.Fastening.
C.Preserving. D.Presenting.
3.What is the result of sunflowers being stopped from moving?
A.They won’t grow well.
B.They will grow faster than usual.
C.They won’t swing back though set free.
D.They will produce a number of new genes.
4.What would happen to the sunflowers if they became fully grown?
A.They would swing as usual.
B.They would move back and forth.
C.They would stop turning.
D.They would track the sun.
5.Bees are fond of dancing ______________.
A.on cold sunflowers B.in the circle of flowers
C.on warm sunflowers D.on the mature sunflowers
高三英语阅读理解中等难度题查看答案及解析
Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis, Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures (成熟) and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A.To see how sunflowers grow up.
B.To show what sunflowers’ genes are.
C.To study why sunflowers track the sun.
D.To check if sunflowers swing in cloudy days.
2.What does the underlined word “staking” probably mean in Paragraph 3?
A.Tracking. B.Fining.
C.Growing. D.Searching.
3.What is the result of sunflowers being stopped from moving?
A.They will produce a number of new genes.
B.They will grow faster than usual.
C.They won’t swing back though set free.
D.They won’t grow well.
4.What is the advantage of sunflowers’ dance to the sun?
A.They attract more insects. B.They save more energy.
C.They mature more rapidly. D.They produce more flowers.
高三英语阅读理解中等难度题查看答案及解析
Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis’ Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the cast sides of their stems grew more rapidly than the west sides. Ai night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day, or on the other side at night. A plant growth-regulating hormone, called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said. “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A.To see how sunflowers grow up.
B.To show what sunflowers’ genes are.
C.To study why sunflowers track the sun.
D.To check if sunflowers swing in cloudy days.
2.What does the underlined word “slaking” probably mean in Paragraph 3?
A.Tracking. B.Fastening.
C.Preserving. D.Researching.
3.What is the result of sunflowers being stopped from moving?
A.They won’t grow well.
B.They will grow faster than usual.
C.They won’t swing back though set free.
D.They will produce a number of new genes.
4.What is the advantage of sunflowers’ dance to the sun?
A.They attract more insects. B.They save more energy.
C.They mature more rapidly. D.They produce more flowers.
高三英语阅读理解困难题查看答案及解析
Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis, Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures (成熟) and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A. To see how sunflowers grow up
B. To show what sunflowers’ genes are.
C. To study why sunflowers track the sun.
D. To check if sunflowers swing in cloudy days.
2.What does the underlined word “staking” probably mean in Paragraph 3?
A. tracking B. fining
C. growing D. searching
3.What is the result of sunflowers being stopped from moving?
A. They will produce a number of new genes.
B. They will grow faster than usual.
C. They won’t swing back though set free.
D. They won’t grow well.
4.What is the advantage of sunflowers’ dance to the sun?
A. They attract more insects. B. They save more energy.
C. They mature more rapidly. D. They produce more flowers.
高三英语阅读理解中等难度题查看答案及解析
Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.
Harmer, a professor in the University of California at Davis’ Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.
By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.
The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.
When sunflowers track the sun, the cast sides of their stems grew more rapidly than the west sides. Ai night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day, or on the other side at night. A plant growth-regulating hormone, called auxin, appears to be a key driver.
The “dance” to the sun cycle obviously slows when the sunflower matures and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.
“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.
“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said. “We’re currently testing this idea.”
1.Why did Harmer do the experiment on sunflowers?
A. To see how sunflowers grow up.
B. To show what sunflowers’ genes are.
C. To study why sunflowers track the sun.
D. To check if sunflowers swing in cloudy days.
2.What does the underlined word “slaking” probably mean in Paragraph 3?
A. Tracking. B. Fastening.
C. Preserving. D. Researching.
3.What is the result of sunflowers being stopped from moving?
A. They won’t grow well.
B. They will grow faster than usual.
C. They won’t swing back though set free.
D. They will produce a number of new genes.
4.What is the advantage of sunflowers’ dance to the sun?
A. They attract more insects. B. They save more energy.
C. They mature more rapidly. D. They produce more flowers.
高三英语阅读理解困难题查看答案及解析
The year I turned fifty, I resolved to do something new every day. However, balancing 365 new things with work and family, while still managing to do the laundry and get dinner on the table every night, was not always easy. In the early weeks of the project, I found it difficult to find so many new things.
It wasn’t long before my friends learned that I was open to almost anything I could consider a new thing, and the invitations began pouring in not just from friends, but friends of friends. As a result, my life was new. I went dog sledding. I attended a fashion show. I went to numerous lectures on all kinds of topics that I never would have previously considered useful or interesting and found something to appreciate in every single one. I even signed up immediately when learning about a local group trying to get into the Guinness Book of World Records by doing something unusual.
As time went by, whenever I learned about something that seemed remarkable, I did what I could to pursue it. Instead of “Why”, I began to ask “Why not”. Now I find it is easier to just keep my eyes open to the possibilities that surrounded me. It turned out that there were new things everywhere, and all I had to do was make a little effort to enjoy them.
I looked back on the year. It doesn’t matter to me that many of my “new things” weren’t exactly meaningful. What matters is how to make full use of them when discovering there is an endless number of new things for me. It seemed to me an obvious sign that at fifty, my life was full of promise. I could continue to grow, stretch my wings, and learn more every day for the rest of my life. I enjoyed the idea of something new, and it gave me a reason to welcome each day as an opportunity to experience the world a little differently.
1.Which of the following can best describe the author’s feeling according to Paragraph 1?
A.Better late than never. B.Action speaks louder than words.
C.Saying is one thing but doing is another. D.Experience is the best teacher.
2.What’s the author’s attitude toward new things?
A.Skeptical. B.Appreciative. C.Cautious. D.Tolerant.
3.What does the author intend to tell us in the last paragraph?
A.Make the most of new things. B.Wait for your life to start over.
C.Try to find more new things. D.Never say never when in trouble.
4.What can be a suitable title for the text?
A.Dream for a New Life B.The Value of Friendship
C.Remarkable New Things D.A Year of New Things
高三英语阅读理解简单题查看答案及解析
High expectations in finding jobs make young people ________ miss job interviews and turn down offers.
A. naturally B. completely C. formally D. frequently
高三英语单项填空中等难度题查看答案及解析
With fuel costs rising and airlines finding more fees to impose on travelers every day, airfare isn’t getting any cheaper. Since you can’t drive to all your dream destinations, flying is the only way to go sometimes and, undeniably, the fastest. Luckily, there are plenty of ways to find the most affordable fares and also avoid paying as many extra charges as possible when you plan ahead.
Getting the best fare. Airlines put out their fare sales on Tuesday morning, making this day the best day to book a flight for less.
Fly during the least popular times. Tuesday, Wednesday and Saturday are the slowest days to fly, which means cheaper deals than the rest of the week. You can also find reduced rates on early morning flights, since many people don’t like to get up before the sun to get to the airport. Earlier boarding times can also considerably cut down your chances of getting bumped on an overbooked flight or delayed because of other delayed flights or mechanical issues.
Choose your seat later. Some airlines charge you to pick your seat when you book online, adding even more to the bottom line of your ticket cost. If you show up early on your travel day, you can still get suitable seats. Some of the best seats get held back until flight day, unless others are willing to pay extra for them ahead of time, so you still have the chance at one of those.
Fly on holidays. You already know that summer is the most expensive time to fly, and even though most other times are more affordable, the days surrounding holidays can be crazy. Save big if you’re willing to travel on major holidays, such as Thanksgiving and Christmas.
Don’t wait until the last-minute to book. Many travelers don’t know that there’s a sweet spot for booking and getting the best price on your tickets. Book too early or too late and you could end up paying more than you need to. The best time to book is between three months and six weeks from when you want to travel.
Avoiding extra fees Airlines will charge for just about anything these days. Some have even toyed around with charging customers for using the restroom. All those extra fees can certainly add up, but there’s no reason to pay them if you don’t have to. Here are some tips to keep money in your wallet once you get to the airport.
Avoid the upgrade it's not necessary. Sometimes upgrades are free, but mostly you will be charged for seeking a last-minute bump to first class, and the cost can be hefty.
Fly carry-on only. Baggage fees vary wildly, but almost all airlines charge them and charge big. Why pay for your clothes to fly with you? If everyone in your travel party checks a bag, your bill can be astronomical before you ever even get to your destination. It’s easy to reduce the amount of stuff you pack: Make sure all your clothing coordinates, so you can take less and still make more outfit combinations, take only two pair of shoes, plan to do a bit of laundry on your trip and bring only travel-sized toiletries.
Pack your own snacks. Unless you’re flying internationally, it’s rare your flight comes with a free meal. Snacks on the plane are not cheap and almost never healthy. Don’t rely on what’s on the small menu and instead tuck some of your own snacks — granola bars, homemade muffins, fruit and trail mix all make fantastic travel foods — into your bag and eat a lot better, and cheaper, than other passengers.
Do you have a tried and true method of getting the best deal on your flights? Let us know.
1.Tuesday is the best to book a ticket at a lower cost for ________.
A. fewer people travel on Tuesday.
B. the flights are slower than usual.
C. fare sales are usually announced on Tuesday.
D. flights are seldom delayed on Tuesday.
2.Which of the following will help to cost you less for a flight?
A. Book your flight on Thursday.
B. Travel surrounding Christmas.
C. Pick your seat the moment you book online.
D. Book early morning flights.
3.The underlined word “hefty” here has the same meaning as ________.
A. large B. heavy C. fierce D. acceptable
4.To save the cost for the flight, you should ________.
A. check whether the upgrade is free before you bump to the first class
B. make sure your clothes and shoes are fit for a lot of walk
C. share your own snacks with other passengers
D. plan to do the washes on flight
高三英语阅读理解中等难度题查看答案及解析
With fuel costs rising and airlines finding more fees to impose （强加，征税）on travelers every day, airfare isn’t getting any cheaper. Since you can’t drive to all your dream destinations, flying is the only way to go sometimes and, undeniably, the fastest. Luckily, there are plenty of ways to find the most affordable fares and also avoid paying as many extra charges as possible when you plan ahead.
Get the best fare. Airlines put out their fare sales on Tuesday morning, making this day the best day to book a flight for less.
Fly during the least popular times. Tuesday, Wednesday and Saturday are the slowest days to fly, which means cheaper deals than the rest of the week. You can also find reduced rates on early morning flights, since many people don’t like to get up before the sun to get to the airport. Earlier boarding times can also considerably cut down your chances of getting bumped on an overbooked flight or delayed because of other delayed flights or mechanical issues.
Choose your seat later. Some airlines charge you to pick your seat when you book online, adding even more to the bottom line of your ticket cost. If you show up early on your travel day, you can still get suitable seats. Some of the best seats get held back until flight day, unless others are willing to pay extra for them ahead of time, so you still have the chance at one of those.
Fly on holidays. You already know that summer is the most expensive time to fly, and even though most other times are more affordable, the days surrounding holidays can be crazy. Save big if you’re willing to travel on major holidays, such as Thanksgiving and Christmas.
Don’t wait until the last-minute to book. Many travelers don’t know that there’s a sweet spot for booking and getting the best price on your tickets. Book too early or too late and you could end up paying more than you need to. The best time to book is between three months and six weeks from when you want to travel.
1.The passage is intended to _______.
A. inform us how to book a cheaper ticket
B. tell us how to choose the seat and time for a flight
C. persuade us into travelling by air
D. inform us of some best ways to save money on a flight
2.Which of the following statements is not true?
A. Airline travelers are supposed to pay more for the rising fuel costs
B. Early morning flight will help avoid some bumps and delays.
C. You can only book your seat online before or on your flight day.
D. Booking too early may cost you more money on your tickets.
3.Which is the best time to book the flight for October 2nd?
A. May 15th B. August 15th
C. June 15th D. September 15th
高三英语阅读理解中等难度题查看答案及解析
Young sunflowers face the sun as it rises in the east and follow it across the sky until it sets in the west. Why does this happen? A team of scientists has finally been able to figure 1. how and why young sunflowers move.
Older sunflowers always face east. However, as it 2.(turn) out, an internal（内部的）clock helps young sunflowers track the sun so that they can grow better. US biologist Stacey Harmer and her colleagues had it 3. (explain) in a recent paper published in the journal Science on Aug. 5.
4. (depend) on the time of day, certain growth genes seem to work to different degrees on different 5. (side) of young sunflowers’ stems（茎）. The east side of their stems grows faster during 6. day, causing the stems to 7. (gradual) bend from east to west. The west side grows faster at night, preparing them for the next morning.
All this move is highly 8. (benefit) to sunflowers. The team found that flowers kept away from the sun had leaves 9. were 10 percent smaller on average. According to Harmer, sunflowers which 10. (face) with the sun receive more bees and other insects because they like warm flowers.
高三英语语法填空中等难度题查看答案及解析