It is easy for us to tell who our family members are, but do plants recognize(识别

It is easy for us to tell who our family members are, but do plants recognize(识别

题型:不详难度:来源:
It is easy for us to tell who our family members are, but do plants recognize(识别) their own family? Some do, scientists say, according to a report by Science News in early 2010.
Guillermo P. Murphy and Susan Dudley are two plant scientists from McMaster University in Hamilton, Canada. They did a few experiments with Jewelweeds, a kind of flower that grows in wet, shady spots. They found that the flowers seem to know their own flower family. In their experiments, Murphy and Dudley planted jewelweeds in pots with either siblings or strangers.
When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone. This response(反应)suggests that plants are competing with strangers for sunlight, since a plant with more leaves can receive more light and make more food. Jewelweeds usually grow in the shade, where sunlight is not enough.
When jewelweed seedlings(幼苗)were planted with siblings, they grew a few more branches than they usually would if they were alone – but they did not start growing lots of extra leaves. This behavior suggests the plants are more likely to share resources, rather than compete.
According to the Science News report, Jewelweeds are not the first plants that plant scientists have studied for family recognition. In 2007, Dudley and her team studied the Great Lakes sea rocket, a plant that grows on the beach – where it may be hard to get fresh water. In that experiment, the scientists found that when sea rockets were planted with siblings, they tolerated each other. But when they were planted with strangers, the sea rockets reacted by working extra hard to grow lots of roots.
Dudley says this just because sea rockets, on the beach, get plenty of sun but struggle for water – so when they’re threatened, they compete for water. Jewelweeds have plenty of water but have to compete for sunshine, so they grow more leaves.
小题1: What does the underlined word siblings mean?
A.Flowers come from foreign countries.
B.Plants growing in different environments.
C.Flowers planted with lots of strangers.
D.Plants that are the same kind.
小题2: In the text, the writer mentioned the experiments of Jewelweeds to         .
A.make a comparisonB.introduce a topic
C.describe a pretty flowerD.build a new theory
小题3: According to the passage, flowers planted alone will         .
A.grow more leaves than those planted in groups
B.become taller than those with more branches
C.grow fewer leaves than those planted with strangers
D.become ill easily because they can’t get enough shade
小题4: What can be the best title for the passage?
A.New Discoveries about Plants
B.How Plants Compete with Each Other
C.Family Recognition among Plants
D.Jewelweeds and the Great Lakes Sea Rockets

答案

小题1:D
小题2:B
小题3:C
小题4:C
解析

试题分析:这篇文章讲的是科学家通过做实验,发现将一种植物与不同种类的植物种植在一起,它会和其他植物竞争养分,将会长的更好,如果单独种植的话,则会分享资源,而不竞争。
小题1:推断题。由第二段最后一句In their experiments, Murphy and Dudley planted jewelweeds in pots with either siblings or strangers.在他们的实验中,Murphy and Dudley将凤仙花要么和同类植物种植在一起,要么和不同的植物种植在一起。由后面的词义可推出siblings的意思是同类植物。故选D
小题2:推断题。从第一自然段Some do, scientists say, according to a report by Science News in early 2010.可知植物也能够分辨出它的同类,第二自然段对这个说法进行了一项有关jewelweeds凤仙花的研究,所以在此是为了点明主题。
小题3:细节题。由第三段第一句When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone.当把凤仙花和不同种类的植物种植在一起时,它就会比单独种植时生长出更多的叶子。故可知,答案选C
小题4:主旨题。这篇文章讲的是科学家通过实验,发现植物也可以辨别出哪些植物与自己是同一种类的。故选C.
点评:本文较难,科技类的文体是比较繁琐的,因为专有名词较多。学生在解答这类题目时,首先对文章有大致的掌握,对于文章一遍没有看懂时,可以先看题目,按照文章题目的提示,再在文章中找出相对应的地方,然后仔细分析文章的上下文,同时对于专有名词可以用笔画出,通过多个地方的比较就可以猜出意思了。
举一反三
阅读短文,根据短文内容回答问题。(共10分,每小题2分)
Do you want to keep your brain active and your memory strong? Here are some useful ways:
Choose the Brain Food
A proper diet will help keep your mind running strong all day long. Make sure to include plenty of fruits and green vegetables. Some of the best foods include: blueberries, blackberries, fish and fish oil, eggs, strawberries and so on.
Exercise
Get your body moving and your memory will soon follow. Exercise improves the heart’s blood flow. This, in turn, helps the brain function better and stay sharper.
Pick up a Book
The key to keeping your memory quick is to continue to challenge it. Try to always have a book in hand. After you’ve done reading a section or two, question and review the material you’ve read. Try to imagine what you’re reading. Discuss what you’ve read, and talk about it with friends or join a book club.
Develop Interest
We remember new things because we enjoy them. Find ways to make a boring subject fun by connecting it to something you already know. You can use your imagination and create a fun story behind a subject to help make it easier to remember.
Repeat after Me
When learning new information, the more you repeat it, the more likely you will be able to remember that information. Practice is the key to lasting memory.
Share with Others
Don’t keep your knowledge stored up. Teaching others is another great way to improve memory skills. Don’t be afraid of taking on new challenges. After learning something, it’s necessary to put the new information to use.
小题1: What will help keep the mind running strong?
小题2: What’s the key to keeping your memory quick?
小题3: Why do you remember new things?
小题4: How many useful ways are mentioned in the passage?
小题5: What does the writer tell us in the passage?
题型:不详难度:| 查看答案
Just a Quick Nap(打个盹儿)
  Do you feel a little sleepy after lunch? Well, that’s normal. Your body naturally slows down then. What should you do about it? Don’t reach for a coffee! Instead, take a nap.
  It’s good to have a daily nap. First of all , you are more efficient(有效的) after napping. You remember things better and make fewer mistakes. Also, you can learn things more easily after taking a nap. A nap may increase your self-confidence and make you more active. It may even cheer you up. But, there are some simple rules you should follow about taking a nap. First, take a nap in the middle of day, about eight hours after you wake up. Next, a 20-minute nap is best. If you sleep longer, you may fall into a deep sleep. After waking from a deep sleep, you will feel worse. Also, you should set an alarm clock. That way, you can fully relax during your nap. You won’t have to keep looking at the clock, so you don’t oversleep.
  Now, the next time you feel sleepy after lunch, don’t get stressed. Put your head down, close your eyes, and catch forty winks.
小题1: After taking a nap, you may feel more     .
A.tiredB.confident
C.sleepyD.excited
小题2:The proper period of time for taking a nap is    .
A.the shorter the better
B.as long as you like
C.the longer the better
D.about twenty minutes

题型:不详难度:| 查看答案
完形填空(15分)
Do you often  1 your parents? You may say “Of course, I  2 . I buy a present for my mother on Mother’s Day and on Father’s Day, I give my father  3 , too.” But what about the other days of the year?
I have a friend  4 parents live in another city. One day I went to see her. We had a nice  5 . Then she wanted to  6 , so she dialed(拨号) the number, but then she  7 the phone. After about fifteen  8 , she dialed the number “Hi, Mom.”
Later I asked, “  9 did you dial the number twice?” She smiled, “My parents are old and  10 . They can’t get close to the telephone  11 . I always do so when I call them. I just want to give them  12 time to answer the call.”
My friend is a good girl. She is  13 thinking about her parents. You also want to be a  14 child, right? Please always remember to 15 your parents in every situation, not just on some important days.
小题1:A、think of            B、think with         C、think
小题2:A、will               B、do                 C、won’t
小题3:A、a cake            B、a kiss              C、a present
小题4:A、who                 B、which                C、whose
小题5:A、sing              B、conversation         C、drink
小题6:A、make a call         B、pay a visit         C、have a rest
小题7:A、put down            B、put away             C、put off
小题8:A、seconds            B、minutes            C、hours
小题9:A、How                 B、What                C、Why
小题10:A、fast             B、slow              C、healthy
小题11:A、quick             B、quickly             C、slowly
小题12:A、little             B、quick                C、enough
小题13:A、always            B、never                C、seldom
小题14:A、bad               B、clever              C、good
小题15:A、think of          B、look after           C、ring up
题型:不详难度:| 查看答案
Because earthquakes happen without warning, it’s important to take steps now to prepare. Because you don’t know where you will be when an earthquake happens, prepare some supplies(急需品) for your home, work place, and car.
1.Water
A person needs at least 1/2 gallon(加仑,容量单位) of water daily just for drinking. Store at least 1 gallon of water per(每一个) person per day and be prepared for a 72 hour period. It is suggested that you buy bottled water. Keep bottled water in its original container(容器) and do not open it until you need to use it. Also, do check the “use by” date.
2.Food
It’s always a practical idea to keep a supply of non perishable(不易腐烂的) food on hand. Have an enough supply of canned(灌装的) food, powdered milk(奶粉), dried fruits, non salted nuts and canned juices for at least 72 hours.
3.Flashlights(手电筒) and spare batteries(备用电池)
Keep a flashlight beside your bed, at your place of work, and in your car. Do not use matches or candles after an earthquake until you are sure that no gas leaks(泄漏).
Prepare a battery powered(装电池的) radio and spare batteries. Most telephones will be out of order(发生故障), so radios will be your best source of information.
4.Clothes
If you live in a cold place, you must think about warmth. You might not have heat after an earthquake. Think about your clothing and bedding supplies.
根据短文内容,选择正确答案(10分)
小题1:Why should people prepare themselves for an earthquake?
A、Because earthquakes can be known before they happen.
B、Because earthquakes take place without warning.
C、Because earthquakes usually take place in the neighborhood.
小题2:About the prepared water, which description is RIGHT?
A、A person should prepare 0.5 gallon of water for one day.
B、You’d better use your own containers to keep water.
C、You shouldn’t open the bottled water until you need it.
小题3:You should prepare all of the following except       .
A、powdered milk
B、fresh vegetables
C、dried fruits
小题4:According to the article we know that        .
A、we need to prepare some supplies only at home
B、a telephone is the most important prepared thing
C、flashlights but not matches are first used after earthquakes
小题5:If you live in a cold place, you should prepare       .
A、some warm clothes and bedding supplies
B、some hot water
C、some batteries
题型:不详难度:| 查看答案
Some people think that as more and more people have televisions in their homes, fewer and fewer people will buy books and newspapers. Why read an article in the newspaper, when the TV news can bring you the information in a few minutes and with pictures? Why read the life story of a famous man, when a short television program can tell you all that you want to know?
Television has not killed reading, however. Today, newspapers sell in very large numbers. And books of every kind are sold more than ever before. Books are still a cheap way to get information and enjoyment. Although some books with hard covers are expensive, many books are printed today as paperbooks (平装本), which are quite cheap. A paperback collection of short stories, for example, is always cheaper than an evening at the cinema or the theater, and you can keep a book for ever and read it many times.
Books are a wonderful provider of knowledge and pleasure and some types of books should be in every home. Every home should have a good dictionary. A good encyclopedia (百科全书), though expensive, is useful, too, because you can find information on any subject. Besides, you can have such books as history books, science textbooks, cookbooks, and collections of stories and poems. Then from time to time you can take a book of poems off your shelves and read the thoughts and feelings of your favorite poets.
小题1:It can be inferred from the passage that ____.
A.Fewer and fewer people will buy books.
B.A good dictionary should be kept in every home.
C.Books with hard covers sell better than paperbooks.
D.More people like TV programs about famous men.
小题2:What does the sentence “Television has not killed reading, however.” underlined in the second paragraph suggest?
A.People only need reading, though.
B.Reading is still necessary today.
C.Reading is more fun than television.
D.Watching television doesn’t help reading.
小题3:What can we learn from the passage?
A.TV programs are a chief provider of knowledge.
B.Cinemas are the best choice in getting information.
C.Reading is cheap way of learning and having fun.
D.Newspapers are an expensive way to enjoy oneself.

题型:不详难度:| 查看答案
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