题目内容
A mosquito is an insect that is found all over the world.There are thousands of different kinds of mosquitoes in many different sizes and colors.The female mosquito needs blood from vertebrates (脊椎动物)to lay eggs and produce more mosquitoes.She has a special part of her mouth that she uses to suck blood,and her saliva(spit)thins the blood so she can drink it.In fact.It’s the mosquito’s saliva that makes the bites itch(痒)!
A person who gets bitten by a mosquito will notice a wheal,which is a bump around the bite.
The wheal will be round,with pink or red around the edge and white in the middle.The wheal will witch a lot.Soon the wheal will disappear, but the itch will stay.
If you’ve been bitten by a mosquito,wash the bite with soap and waterk#s^5*u.Put on some calamine lotion to help stop the itching,or an adult can find an anti-itch cream at the drugstore for you.Placing an ice pack on the bite may also help.Tell an adult you’ve been bitten by a mosquito,especially if you live in the easterk#s^5*un United States.But if you develop an allergic reaction and feel dizzy or sick,tell a doctor immediately.He can treat allergic reactions with sole medicine.
The best way to avoid mosquito bites is to wear an insect repellent.Repellents that include one of these ingredients are best:BEET and lemon eucalyptus.Ask a parent to help you apply them.
Since mosquitoes lay their eggs in water,it’s also a good idea to empty out buckets,flower pots,toys and other things in your yard that may have collected water during a rainstorm.And when it’s possible,you’d better wear long-sleeved shirts and long pants to keep mosquitoes away from your skin.
60.What makes you itch after the mosquitoes’ bites?
A.A bump around the bite. B.The mosquito’s saliva.
C.Some calamine lotion. D.An antic-itch cream.
61.The underlined word “wheal”(Paragraph 2)is closest in meaning to________.
A.a small mouth that can prevent an insect
B.a small mark after an insect bite that usually itches
C.an illness after an insect bite that always spreads nearby
D.an illness from mosquitoes’ bites and other pollution diseases
62.Which of the following is TRUE according to this passage?
A.There are thousands of mosquitoes in the same sizes and colors.
B.The wheal will never disappear forever but the itch will disappear soon.
C.Ask a doctor for some medicine if you develop an allergic reaction for the bite.
D.Ask a parent for an insect repellent if you see mosquitoes laying their eggs in water.
60—62 BBC
根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
It’s summertime-time once again for mosquitoes to make their appearance. And once they appear, mosquitoes are a total pain. They land on you, bite you, suck out some blood and leave behind an itchy welt(发痒的红肿).
1 Female mosquitoes must find blood in order to reproduce, so mosquitoes come equipped with finely tuned sensors to help them locate the blood they need.
Mosquitoes’ weapons
Mosquitoes have perfected three different types of sensors. First, mosquitoes can sense several different chemicals. Mosquitoes can smell carbon dioxide and lactic acid(乳酸)up to 100 feet away. 2
Second, mosquitoes have very good eyesight. If you are wearing clothing that contrasts with the background, and if you move while wearing that clothing, mosquitoes can see you. It’s a good bet that anything moving is alive, and therefore full of blood.
Finally, mosquitoes come equipped with temperature sensors, so they can find warm-blood mammals and birds very easily.
3 The female mosquito sticks her proboscis(喙)into you. She sucks about five microliters of your blood into her abdomen.
After she has bitten you, some saliva(唾液)remains in the wound. 4 The area swells and you tich. Eventually, the selling goes away, but the itch remains until your immune cells break down the saliva proteins.
Our defense methods
Because mosquitoes are both a nuisance(讨厌的东西) and a danger, people prefer to stay away from mosquitoes. One way to do that is to use a chemical called DEET, which seems to black a mosquito’s chemical sensors. 5 In some cities there are even trucks that drive around town to spray for mosquitoes. Finally there are to traps. The most popular traps turn propane(丙烷) into carbon dioxide and warmth to attract mosquitoes. Over time, by catching large numbers of mosquitoes, these traps can cause the collapse of the mosquito population in the area.
| A.Another way to control mosquitoes is with insecticides(杀虫剂) that kill them. |
| B.How mosquitoes work is unknown to most of us. |
| C.Once a mosquito lands on you, it is time to bite. |
| D.Some bites of mosquitoes are more serious than you thought. |
F. The proteins from the saliva create an immune response from your body.
G. But if you ignore the fact that mosquitoes are so annoying they really are amazing.