Frogs, toads and salamanders usually make us think of green, slimy little monsters. These monsters actually belong to a very special class of animals called the amphibians. Amphibians can live both on land and in the water. They commonly inhabit ponds, rivers, marshes and other wetlands.
Today, amphibians are becoming extinct very quickly from all the six continents where they are found. More than 25 countries are reporting sharp drops in the populations of amphibians. In some places, embryos (胚胎) are dying; in others, adults are missing. Why are they dying off?
Scientists blame human interference. Industrial waste and toxic gases given out by factories, manufacturing plants and cars are steadily poisoning the breeding grounds of amphibians. Chemicals such as sulphur dioxide rise high into the atmosphere and mix with rain. This makes the rain acidic and thus kills off delicate amphibian embryos.
More rare species of amphibians are already gone. Costa Rica's Golden toads have not been seen since 1989. The Australian Gastric Brooding frogs are extinct. Leopard frog numbers are dropping in the Rocky Mountains. Leopard frogs live in the wetland regions in these areas. The wetlands are being drained to make way for highways, industry and new housing.
Another threat to the amphibians is the increased ultraviolet radiation. Ultraviolet rays come from the sun and are extremely harmful to living things. They can cause skin cancer in humans. Luckily for us, ultraviolet rays are blocked by a thick layer of ozone above the earth's atmosphere. Ozone is a special kind of oxygen which absorbs ultraviolet radiation. Now, the ozone layer is being destroyed by chemicals called CFC's which are given off by factories. A hole in the ozone layer was discovered over Antarctica in the late 1980’s. As a result, more ultraviolet rays are reaching the earth and more amphibians are dying.
Just as the emergence of new infectious diseases such as Bird Flu are a threat to human and animal populations across the world, amphibian species are also facing their most significant threat from a little understood disease. A chytrid fungus is understood to be of the major causes of frog death across the world.
(Note: Answer the questions or complete the statements in NO MORE THAN TWELVE WORDS)
81. _____________________________________indicate that amphibians are dying out quickly.
82. What’s the destructive force of acid rain?
_________________________________________________________________________.
83. The ozone layer protects people by _____________________________________________.
84. List at least two major factors that lead to the extinction of amphibians.
_________________________________________________________________________.
冲刺100分单元优化练考卷系列答案科目：高中英语 来源：广东省执信中学2009-2010学年度高二下学期期中考试 题型：阅读理解
D
Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm-blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.
Getting enough water to survive is a major problem for all desert animals. Some desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.
Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.
The camel---often called the ship of the desert---is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps. A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.
71. Desert animals are usually more active at night because ______.
A. it is cooler at night B.it is easier to find water
C.they like the dark D. they are less likely to be attacked at night
72. Which of the following desert animals can get water only from the food?
A. The camel. B. The kangaroo rat. C. The frog. D. The toad
73. Which of the following is TRUE according to the passage?
A. All the desert animals rest during the day.
B. All the desert animals don’t rest during the day.
C. Cold-blooded desert animals don’t rest during the day.
D. None of the cold-blooded desert animals go out during the day.
74. The title for this passage could probably be ________.
A. Hot Deserts B. Desert Animals
C. How Desert Animals Get Water D. Ways To Escape the Desert Heat
75. The underlined word “burrows” in the first paragraph can be replaced by _________.
A. holes B. caves C. rooms D. Openings
查看答案和解析>>
科目：高中英语 来源： 题型：阅读理解
Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm- blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles（爬行动物） move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.
Getting enough water to survive is a major problem for all desert animals. Some desert animals, like desert birds, manage to find water holes. Other desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.
Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted(适应) to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles(水坑) dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.
The camel ― often called the ship of the desert ― is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps(驼峰). A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.
41. Desert animals are usually more active at night because _____.
A. it is cooler at night B. it is easier to find water
C. they like the dark D. they are less likely to be attacked at night
42. Which of the following desert animals can get water only from the food?
A. The camel. B. The kangaroo. C. The frog. D. The rat.
43. Which of the following is TRUE according to the passage?
A. All the desert animals rest during the day.
B. All the desert animals don’t rest during the day.
C. Cold-blooded desert animals are out most of the day.
D. None of the cold-blooded desert animals go out during the day.
44. The title for this passage could probably be _____.
A. Hot Deserts B. Desert Animals
C.
45. The underlined word “burrows” in the first paragraph can be replaced by _____.
A. holes B. caves C. rooms D. openings
查看答案和解析>>
科目：高中英语 来源： 题型：阅读理解
Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm-blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.
Getting enough water to survive is a major problem for all desert animals. Some desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.
Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.
The camel---often called the ship of the desert---is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps. A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.
71. Desert animals are usually more active at night because ______.
A. it is cooler at night B.it is easier to find water
C.they like the dark D. they are less likely to be attacked at night
72. Which of the following desert animals can get water only from the food?
A. The camel. B. The kangaroo rat. C. The frog. D. The toad
73. Which of the following is TRUE according to the passage?
A. All the desert animals rest during the day.
B. All the desert animals don’t rest during the day.
C. Cold-blooded desert animals don’t rest during the day.
D. None of the cold-blooded desert animals go out during the day.
74. The title for this passage could probably be ________.
A. Hot Deserts B. Desert Animals
C. How Desert Animals Get Water D. Ways To Escape the Desert Heat
75. The underlined word “burrows” in the first paragraph can be replaced by _________.
A. holes B. caves C. rooms D. openings
查看答案和解析>>
科目：高中英语 来源： 题型：阅读理解
Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm-blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.
Getting enough water to survive is a major problem for all desert animals. Some desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.
Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.
The camel---often called the ship of the desert---is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps. A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.
71. Desert animals are usually more active at night because ______.
A. it is cooler at night B.it is easier to find water
C.they like the dark D. they are less likely to be attacked at night
72. Which of the following desert animals can get water only from the food?
A. The camel. B. The kangaroo rat. C. The frog. D. The toad
73. Which of the following is TRUE according to the passage?
A. All the desert animals rest during the day.
B. All the desert animals don’t rest during the day.
C. Cold-blooded desert animals don’t rest during the day.
D. None of the cold-blooded desert animals go out during the day.
74. The title for this passage could probably be ________.
A. Hot Deserts B. Desert Animals
C. How Desert Animals Get Water D. Ways To Escape the Desert Heat
75. The underlined word “burrows” in the first paragraph can be replaced by _________.
A. holes B. caves C. rooms D. openings
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话：027-86699610 举报邮箱：58377363@163.com
