Rice plants normally grow well in still water. But most will die if they are completely underwater for more than four days. Now, researchers have identified a gene (基因) that helps rice survive longer underwater. They say the discovery will lead to new kinds of rice plants that can survive flooding, and therefore reach their final aim, ensuring more dependable food supplies.
Tests are now being done in
On a genetic (遗传的) map of rice, the scientists became interested in a group of three genes. They experimented with one of them, a gene known as Sub-One-A. They found that when this gene becomes very active, it improves the ability of rice to survive longer when rice is covered by water. They believe it succeeds because it affects the reaction to hormones (荷尔蒙). They control the ability of a flooded plant to survive. Placing the gene into rice plants that are especially good for conditions in
The researchers are now trying to identify all the genes governed by the Sub-One-A gene. Being able to leave water on rice plants for an additional week might also help farmers prevent the growth of weeds. Less weed growth around their crops would mean less need for herbicide (除草剂) chemicals.
41. Crop loss depends on all the following conditions EXCEPT _______.
A. soil conditions and plant age
B. the amount of water the plant stands in
C. the amount of fertilizer used on the crop
D. the amount of time the plant is underwater
42. What is the final aim of this research?
A. To identify the gene that helps rice survive underwater.
B. To increase the ability of rice to fight against floods.
C. To help farmers spend less time removing weeds.
D. To make sure of enough food supplies.
43. What does the underlined word “They” in Paragraph 3 refer to?
A. Genes. B. The experiments.
C. Genetically engineered plants. D. Hormones.
44. What would be the best title for the passage?
A. Rice research is going on in
B. How to reduce the influence of floods on rice
C. Gene researchers work on flood-resistant rice
D. A great discovery in the agricultural field
学练快车道快乐假期寒假作业系列答案科目：高中英语 来源： 题型：阅读理解
阅读下面短文，根据所读内容在表格中的空白处填入恰当的词。
注意：每个空格只填一个单词。
Fruit also makes up a flowering plant. It carries the seeds . The purpose of fruit is to protect a plant’s seeds and help them get spread about. Wind and water spread seeds .So do animals when they eat fruit and drop the seeds .
There are two main types of fruit: fleshy and dry. Fleshy fruits are soft and juicy , the way we usually think of fruits . Peaches ,plums ,and apples are all fleshy fruits . Dry fruits are thin and hard . Grains like wheat and rice , or nuts are dry fruits.
You’ve eaten seedless oranges and grapes . How can they be fruits? It’s because people have changed the way they grow fruit. They can now grow seedless fruit . Seedless fruit comes from special plants called hybrids(杂交生物体) . A hybrid is made by combining two varieties of a fruit to form a new variety . This hybrid grows and produces seeds . But the plants grown from these seeds are seedless . These plants cannot reproduce themselves.
A tomato is a vegetable , right? No , it’s actually a fruit . Other food we think of as vegetables—such as squash , peppers ,and eggplant—also are fruit . They’re fruit because they carry seeds and develop from flowers . Here’s another surprise . Scientists classify the tomato as a berry(浆果) . In addition , they don’t consider some fruits we call berries to be true berries because a berry is normally a type of fruit with a lot of seeds inside it . Technically , a strawberry , isn’t a berry , because it has its seeds on the outside . The red part is just the tip of the strawberry stem that’s enlarged.
Fruits are a source of nourishing(滋养) substances that keep us alive and healthy . For example , they contain many vitamins , especially vitamins A and C, and many minerals . They also provide fibre for a healthy digestive system and carbohydrates that the body needs to make energy.
| Title： | |
| Basic knowledge | Being of a flowering plant and carrying seeds. Protecting a plant’s seeds and helping spread them about. Mainly on wind , water and animals to spread. |
| Fleshy fruit :Juicy and , like peaches , plums ,apples ,etc . Dry fruit : Thin and hard , like wheat ,rice , nuts ,etc . | |
| Fruit seeds | Coming from a ,which is made by combining two kinds of fruit to form a new kind. |
| Some surprises | Tomato , squash ,peppers and eggplant are fruits because they carry seeds and develop from . Some fruits like strawberry aren’t technically berries because they have seeds on the . |
| Being to humans | Keeping people alive and . Providing vitamins , fiber and carbohydrates. |
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科目：高中英语 来源：2013届安徽泗县双语中学高三5月模拟测试英语卷（带解析） 题型：阅读理解
Some plants get so hungry they eat flies, and even small frogs. What's more amazing is that these plants occur naturally (in special environments) in every state. In fact, they're found on every continent except Antarctica.
You've probably seen a Venus' flytrap -- a small plant, which grows 6 to 8 inches tall in a container. At the end of its stalks (茎) are leaves that act like traps (陷阱). Inside each trap is a lining of tiny hairs. When an insect lands on them, the traps suddenly shut. Over the course of a week or so, the plant feeds on its catch.
The Venus' flytrap is just one of more than 500 species of meat-eating plants, says Barry Meyers-Rice, the editor of the International Carnivorous Plant Society's Newsletter. He states although you might have read some science-fiction stories, no meat-eating plant does any danger to humans.
Barry says a plant is meat-eating, only if it does all four of the following: "attract, kill, digest, and absorb" some form of insects. Meat-eating plants look and act like other green plants -- well, most of the time.
All green plants make sugar to produce food. What makes meat-eating plants different is their special leaves, which need insects for one reason: nitrogen (氮). Nitrogen is a nutrient that they can't obtain any other way. Why?
Almost all green plants on our planet get nitrogen from the soil. Meat-eating plants can't. They live in places where nutrients are hard to get from the soil because of its acidity. So they've come to rely on getting nitrogen from insects and small animals. In fact, nutrient-rich soft is poisonous to meat-eating plants. Never fertilize (施肥) them! But don't worry, either, if they never seem to catch any insects. They can survive, but they'll grow very slowly.
【小题1】According to the passage, a Venus' flytrap ______.
| A．is a small plant which grows in a container |
| B．is a kind of plant which gets hungry easily |
| C．can trap and feed on some form of insects |
| D．can only grow 6-8 inches tall |
| A．meat-eating plants are found nowhere else except Antarctica |
| B．all green plants get nitrogen from the soil |
| C．meat-eating plants endanger humans in science-fiction stories |
| D．the nutrient-poor soil is beneficial to meat-eating plants |
| A．so you'd better fertilize them |
| B．probably because the supply of nitrogen is cut off |
| C．simply because they can't absorb nitrogen from the soil |
| D．and then they will die slowly |
| A．Meat-eating plants look and act like other green plants. |
| B．It's hard to get nutrients in the soil when acidity is high. |
| C．The Venus' flytrap eats flies to get nutrient from them. |
| D．Green plants make sugar at night. |
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科目：高中英语 来源：福建省仙游县金石中学高一下学期unit13-unit15单元测试 题型：阅读理解
B
All of us eat every day, but most of us don’t understand nutrition. We often make mistakes in talking about good diet.
For example, many people think that foods such as rice, bread and potatoes will make one grow fat. In fact, these foods are very good to one’s health. They are good sources of many vitamins. And in comparison with steak and beef, they contain less amount of calories.
Some people don’t like canned(罐装的) or frozen vegetables, because they think fresh vegetables cooked at home are always better. This is again wrong. In fact, whether the vegetables are good or not depends more on how they are prepared. Overcooking, for example, destroys good qualities of vegetables. Vegetables cooked in too much water can use a large amount of vitamins.
It is widely believed extra vitamins provide more energy. But taking more than the body needs doesn’t make it function better.
It is also wrong to say that vegetables grown in poor, worn-out soil are lower in vitamins than vegetables grown in rich soil. The vitamins in our foods are in the plants themselves. They don’t come from the soil. However, the minerals(矿物质) in a plant depend on the minerals in the soil.
In short, there are many false ideas about nutrition. We need to correct them.
1. This passage is mainly about_______.
A. nutrition B. vitamins C. vegetables D. health
2. Rice, bread and potatoes do good to people’s health mainly because_______.
A. they make people fat B. there are lot of vitamins in them
C. they contain less amount of calories compared with steak and beef.
D. both B and C.
3. Why don’t some people like canned or frozen vegetables? Because______.
A. they think fresh vegetables contain less vitamins
B. they think fresh vegetables contain more vitamins than the canned or frozen ones
C. they don’t think the canned or frozen vegetables are fresh
D. they don’t think the canned or frozen vegetables taste as good as the fresh ones
4. Which of the following is true according to the passage?
A. Many people know almost everything about nutrition.
B. Food such as rice, bread and potatoes make people fat.
C. vegetables grown in poor worn-out soil may have the same amount of vitamins as vegetables grown in rich soil.
D. extra vitamins provide less energy.
5. The point of the passage is that______.
A. the minerals in a plant depend on the minerals in the soil
B. people make mistakes when talking about good diet
C. taking more vitamins than the body needs doesn’t make it function better
D. vegetables cooked in too much water can lose a large amount of vitamins
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科目：高中英语 来源：2011届江西省安福中学高三上学期第四次月考英语卷 题型：阅读理解
阅读下面短文，根据所读内容在表格中的空白处填入恰当的词。
注意：每个空格只填一个单词。
Fruit also makes up a flowering plant. It carries the seeds . The purpose of fruit is to protect a plant’s seeds and help them get spread about. Wind and water spread seeds .So do animals when they eat fruit and drop the seeds .
There are two main types of fruit: fleshy and dry. Fleshy fruits are soft and juicy , the way we usually think of fruits . Peaches ,plums ,and apples are all fleshy fruits . Dry fruits are thin and hard . Grains like wheat and rice , or nuts are dry fruits.
You’ve eaten seedless oranges and grapes . How can they be fruits? It’s because people have changed the way they grow fruit. They can now grow seedless fruit . Seedless fruit comes from special plants called hybrids(杂交生物体) . A hybrid is made by combining two varieties of a fruit to form a new variety . This hybrid grows and produces seed
s . But the plants grown from these seeds are seedless . These plants cannot reproduce themselves.
A tomato is a vegetable , right? No , it’s actually a fruit . Other food we think of as vegetables—such as squash , peppers ,and eggplant—also are fruit . They’re fruit because they carry seeds and develop from flowers . Here’s another surprise . Scientists classify the tomato as a berry(浆果) . In addition , th
ey don’t consider some fruits we call berries to be true berries because a berry is normally a type of fruit with a lot of seeds inside it . Technically ,
a strawberry , isn’t a berry , because it has its seeds on the outside . The red part is just the tip of the strawberry stem that’s enlarged.
Fruits are a source of nourishing(滋养) substances that keep us alive and healthy . For example , they contain many vitamins , especially vitamins A and C, and many minerals . They also provide fibre for a healthy digestive system and carbohydrates that the body needs to make energy.
| Title：【小题1】 | |
| Basic knowledge | Being【小题2】 of a flowering plant and carrying seeds. Protecting a plant’s seeds and helping spread them about. Mainly【小题3】 on wind , water and animals to spread. |
| Fleshy fruit :Juicy and【小题4】 , like peaches , plums ,apples ,etc . Dry fruit : Thin and hard , like wheat ,rice , nuts ,etc . | |
| Fruit【小题5】 seeds | Coming from a 【小题6】 ,which is made by combining two kinds of fruit to form a new kind. |
| Some surprises | Tomato , squash ,peppers and eggplant are fruits because they carry seeds and develop from 【小题7】 . Some fruits like strawberry aren’t technically berries because they have seeds on the 【小题8】 . |
| Being 【小题9】 to humans | Keeping people alive and【小题10】 . Providing vitamins , fiber and carbohydrates. |
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科目：高中英语 来源：2010-2011学年北京市东城区高三下学期二模英语试题 题型：阅读理解
A new power plant in Nakoso, Japan, might someday change everything for coal plants．Since the new power plant fired up in September, the designer, Mistubishi, is expecting to prove it's possible to burn coal without polluting．This technology is known as integrated gasification combined cycle （IGCC）．Proving IGCC works should give Mitsubishi's US partner, NRG Energy, the jump other hurdles to building new clean plants．
The project promised to solve the problem of the ages for power plants: how to produce cheap, clean, reliable electricity．No existing technology can do all three perfectly．
The problem is IGCC isn't there yet．It costs about 20 percent more than traditional plants．And even though it's easier to collect the resulting carbon dioxide from an IGCC plant than a traditional plant, there's no proven way to get rid of the greenhouse gas．One plan is to drill a shaft（通道） to pump the carbon dioxide underground, into saltwater formations．But there's no guarantee it will remain underground forever．
NRG administrators think solving the IGCC riddles is worth the trouble because they expect the U．S．will soon limit the amount of carbon dioxide that power generators may give out ．
"With the additional cost of IGCC, to just voluntarily build something that's 20 percent more expensive, that’s commercial suicide," NRG chief administrator, David Crane said．
NRG administrators expect the cost to decline after six or seven plants are built．But other industry experts think it will take about a dozen plants for the price to be competitive with traditional coal plants．
Takaya Watanabe, a vice general manager of Mitsubishi, admits that the cost challenges are difficult．“It’s good for a company to say we want to be green, but unless someone is willing to pay, it's a dream．It won't keep our family eating rice," he said．
1.What is expected of the new technology?
A．To make electricity without polluting the air．
B．To produce energy without burning coal．
C．To keep the use of electricity cheaper．
D．To pump carbon dioxide more easily ．
2.What's the biggest problem the companies are faced with?
A．How to pump greenhouse gases．
B．How to deal with the high cost．
C．How to get along with other partners．
D．How to improve the new technology．
3.What can be inferred from the passage?
A．New technologies are unacceptable to people．
B．It's unlikely to build more new power plants．
C．The companies are run on a tight budget．
D．Going green is easier said than done．
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