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  3. Did you know that only the female mosquito bites? Well, it’s true. And it’s not because she’s un friendly; she needs blood to re

Did you know that only the female mosquito bites? Well, it’s true. And it’s not because she’s un friendly; she needs blood to re

admin2010-06-30  40
问题      Did you know that only the female mosquito bites? Well, it’s true. And it’s not because she’s un friendly; she needs blood to reproduce.
     She’s quite selective, and she chooses her victims carefully. First, she uses sensors to find her victim. These sensors are located on her two antennae and her three pairs of legs. With these sensors, she tests your body moisture, body warmth, and chemical substances in your sweat. If she likes what she finds, she bites. But if you don’t appeal to her, she’ll reject you for some one more appetizing.
     If the mosquito likes you, she settles onto your flesh very gently, and she breaks your skin with the tip in front of her nose. This tip is a kind of mouth and it sticks out just below the mosquito’s eyes. It contains six sharp instruments called stylets. She stabs all six stylets into your skin at once, and if she hits a blood vessel, she’ll get a full dinner in about a minute. All this usually takes place too quickly and quietly that you may not have suspected anything was happening.
     Why does your skin itch after the mosquito bites? The itch is not really from the bite. It is from the liquid the mosquito mixes with your blood to keep it from forming into lumps as she sucks it up her proboscis tip. By the time the itching begins, she has gone. Heavy with your blood, she picks a spot--on a leaf or a wall or a stone--to quietly lay her eggs. Just one drop of blood will produce hundreds of eggs.
     All mosquitoes, male and female, pass through their early stages of development in or near water. In fact, mosquito eggs will not hatch without water--although the eggs can survive up to five years on dry land waiting for water. It is not surprising that the heavy rain produce large numbers of mosquitoes.
     Why did nature bother to create mosquitoes? Just to annoy us? Probably that wasn’t the main reason. Male mosquitoes live on the juice of flowers, and they never bite people since they do not need blood to reproduce as the female ones. Of course, mosquitoes have to reproduce, and unfortunately that’s where you and I come in. Like it or not, mosquitoes are here to stay.
Why does rain produce a lot of mosquitoes?
选项 A、Mosquitoes can find enough food in rainy season.
B、Rain makes grass grow fast.
C、Rain provides a good living condition for mosquitoes.
D、Rain provides an abundant supply of water.
答案D
解析 根据文章第五段可知，没有水，蚊子的卵是不能孵化的。大雨可以提供丰富的水源，也正因为如此，大雨能够产生大量的蚊子。A、B文章未提及。C与文意不符，文章第五段第一句只是说雄蚊子和雌蚊子成长早期都是在离水近的地方，并没说大雨可以给蚊子提供好的生存环境。
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