03-02-2015, 06:35 PM
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عضو جديد
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تاريخ التسجيل: Feb 2015
المشاركات: 3
معدل تقييم المستوى: 0
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السلام عليكم
لقيت هذي القطعه في النت الي عنده حل الاسئله ياليت يعطينا جزاكم الله خير
Directions: Read the passage. Then answer questions about the passage below. Slap! Swat! How do those annoying mosquitoes find you? Is it your wonderful personality or is it something else which attracts them? And why are you so rarely able to swat them before they fly off to another feast? There are about 3,500 species of mosquitoes in the world. Not all of them are in your back yard, although sometimes it seems that the summer evening air is filled with them. There are about 200 species of mosquitoes in the United States –– about 80 species have been identified in Florida, which is an ideal breeding area. The word “mosquito” means “little fly” in Portuguese. Mosquitoes are members of the scientific order Diptera, the “True Flies.” Like other “True Flies,” they have wings. But they are different from some True Flies; their wings have scales. These tiny scales help eliminate the effects of friction. This helps the mosquitoes skim quickly and efficiently through the air, making them almost impossible to swat. The familiar high–pitched, annoying buzz of the mosquito comes from the sound of its wings beating 600 times per second! If you want to control the spread of these pesky insects, it is important to know how they live and breed. As you will see, much of their life is spent in water, so getting rid of standing water plays a large role in controlling mosquitoes. There are four stages in the lifetime of a mosquito: egg, larva, pupa, and adult. Mosquito eggs need water to hatch. Different species of mosquitoes prefer different places to lay their eggs. Some prefer to lay their eggs in standing water, such as water in old tires or buckets. Others like to lay their eggs in areas with a lot of organic material, like leaves and grass, so they lay their eggs in marshes and swamps. Some prefer fresh water; some like saltwater. Mosquito larvae are called “wigglers” because they move with jerking movements of their bodies. They spend most of their time under the surface of the water, feeding on leaves and grass. They must have air to stay alive, so they wiggle to the surface. The larvae shed their skin four times as they grow and progress to the third stage, which is the pupa. Mosquito pupae also need air to stay alive. They continue to feed on grasses and leaves under the surface of the water, but they must come up for air. After several days in the pupa stage, the pupae mature into adult mosquitoes. Adult mosquitoes emerge after several days of growth. Some mosquitoes ***** maturity in as few as 5 days, but most require 10–14 days before they ***** maturity. Variations in maturity time is due to differences in species and differences in the temperature of the environment. Adult mosquitoes mate within a few days of their emergence as adults. They eat fruit, nectar, and any other sources of sugar they can find. Female mosquitoes need blood in order for their eggs to develop. After the female has her meal of blood, she rests for two or three days before she lays her eggs. The cycle of eating and laying eggs continues for one or two weeks, which is the lifetime of a mosquito. Now you know that it is the female mosquitoes which bite you. But how do they find you –– their meal of blood? Mosquitoes seek out warmth and movement –– both properties of human beings and other animals. They also seek carbon dioxide, which is exhaled by humans and other animals. So while it is not exactly your wonderful personality which attracts them, the social activities of conversation and laughter –– which involve movement and the exhalation of carbon dioxide –– are what attract these annoying little insects!
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