以下是在线为同学们整理的英语模拟题:长篇阅读,供各位考生参考。
Animals on the Move
A) It looked like a scene from Jaws but without the dramatic music. A huge shark was slowly swimming through the water, its tail swinging back and forth like the pendulum of a clock. Suddenly sensitive nerve ending in the sharks skin picked up vibrations of a struggling fish. The shark was immediately transformed into a deadly, efficient machine of death. With muscles taut, the shark knifed through the water at a rapid speed. In a flash the shark caught its victim, a large fish, in its powerful jaws. Then, jerking its head back and forth, the shark tore huge chunks of flesh from its victim and swallowed them. Soon the action was over.
Moving to Survive
B) In pursuing its prey, the shark demonstrated in a dramatic way the important role of movement, or locomotion, in animals.Like the shark, most animals use movement to find food.They also use locomotion to escape enemies, find a mate, and explore new territories. The methods of locomotion include crawling, hopping, slithering, flying, swimming, or walking.Humans have the added advantage of using their various inventions to move about in just about any kind of environment. Automobiles, rockets, and submarines transport humans from deep oceans to as far away as the moon.However, for other animals movement came about naturally through millions of years of evolution. One of the most successful examples of animal locomotion is that of the shark. Its ability to quickly zero in on its prey has always impressed scientists. But it took a detailed study by Duke University marine biologists S. A. Wainwright, F. Vosburgh, and J. H. Hebrank to find out how the sharks did it. In their study the scientists observed sharks swimming in a tank at Marine land in Saint Augustine, Fla. Movies were taken of the sharks movements and analyzed. Studies were also made of shark skin and muscle.
Skin Is the Key
C) The biologists discovered that the skin of the shark is the key to the animals high efficiency in swimming through the water. The skin contains many fibers that crisscross like the inside of a belted radial tire. The fibers are called collagen fibers. These fibers can either store or release large amounts of energy depending on whether the fibers are relaxed or taut. When the fibers are stretched, energy is stored in them the way energy is stored in the string of a bow when pulled tight. When the energy is released, the fibers become relaxed.
D) The Duke University biologists have found that the greatest stretching occurs where the shark bends its body while swimming. During the bodys back and forth motion, fibers along the outside part of the bending body stretch greatly. Much potential energy is stored in the fibers. This energy is released when the sharks body snaps back the other way.
As energy is alternately stored and released on both sides of the animals body, the tail whips strongly back and forth. This whip-like action propels the animal through the water like a living bullet.
Source of Energy
E) What causes the fibers to store so much energy? In finding the answer the Duke University scientists learned that the sharks similarity to a belted radial tire doesnt stop with the skin. Just as a radial tire is inflated by pressure, so, too, is the area just under the sharks collagen radials. Instead of air pressure, however, the pressure in the shark may be due to the force of the blood pressing on the collagen fibers.
F) When the shark swims slowly, the pressure on the fibers is relatively low. The fibers are more relaxed, and the shark is able to bend its body at sharp angles. The animal swims this way when looking around for food or just swimming. However, when the shark detects an important food source, some fantastic involuntary changes take place. The pressure inside the animal may increase by 10 times. This pressure change greatly stretches the fibers, enabling much energy to be stored. This energy is then transferred to the tail, and the shark is off. The rest of the story is predictable.
Dolphin Has Speed Record
G) Another fast marine animal is the dolphin. This seagoing mammal has been clocked at speeds of 32 kilometers an hour. Biologists studying the dolphin have discovered that, like the shark, the animals efficient locomotion can be traced to its skin. A dolphins skin is made up in such a way that it offers very little resistance to the water flowing over it. Normally when a fish or other object moves slowly through the water, the water flows smoothly past the body. This smooth flow is known as laminar flow. However, at faster speeds the water becomes more turbulent along the moving fish. This turbulence muses friction and slows the fish down.
H) In a dolphin the skin is so flexible that it bends and yields to the waviness of the water. The waves, in effect, become tucked into the skins folds. This allows the rest of the water to move smoothly by in a laminar flow. Where other animals would be slowed by turbulent water at rapid speeds, the dolphin can race through the water at record breaking speeds.
Other Animals Less Efficient
I) Not all animals move as efficiently as sharks and dolphins. Perhaps the greatest loser in locomotion efficiency is the slug. The slug, which looks like a snail without a shell, lays down a slimy trail over which it crawls. It uses so much energy producing the slimy mucus and crawling over it that a mouse traveling the same distance uses only one twelfth as much energy. Scientists say that because of the slugs inefficient use of energy, its lifestyle must be restricted. That is, the animals are forced to confine themselves to small areas for obtaining food and finding proper living conditions. Have humans ever been faced with this kind of problem?
1.According to the passage, a shark can use movement to find food, to avoid being chased by its enemies, and to find a new place to live.
2.Examples of automobiles, rockets and submarines are used to show that human inventions enable us to travel in almost any kind of environment.
3.The skin is the key to the sharks swift locomotion in water.
4.According to the Duke University scientists, when bending its body in swimming, the shark stretch its collagen fibers to the greatest extent.
5.Because it is also inflated by pressure, the area just under the sharks collagen fibers similar to a belted radial tire.
6.A laminar flow is formed when a fish swims slowly through the water.
7.Consuming the equal amount of energy as a slug does, a mouse can travel 12 times as long as a slug.
8.A shark finds its prey by feeling the vibrations of a struggling prey.
9.According to the passage, collagen fibers can be compared to the string of a bow for both of them store energy when stretched.
10.When the shark detects an important food source, some fantastic involuntary changes take place.
中国味的GRE词汇归纳
不同语境掌握GRE词汇的不同意思
那些极易弄混的GRE词汇
GRE核心词汇的近反义词记忆
GRE新手该如何着手词汇
GRE词汇怎么样背诵效率高
十个不得不记的GRE词汇背诵经验
GRE阅读提高第一步
GRE词汇的各种考法分析
GRE易混淆词汇盘点
两个方法对GRE词汇重复记忆
GRE生单词如何理解
一个月背完GRE词汇的心得
改革后的GRE要求的词汇量有多少
GRE常考动词的近义词
记忆GRE词汇需要什么样的诀窍
GRE单词一个月背诵计划
牛人花十天背完GRE词汇
GRE词汇背诵工具选择
GRE阅读速度和记忆提高
粗略法快速记忆GRE词汇
看牛人对GRE词汇背诵的经验总结
3月GRE考试阅读模拟
各种与胜败相关的GRE词汇
GRE阅读主旨题分析
GRE词汇在写作时该注意什么
GRE阅读考题长句子分析
新GRE词汇和旧GRE词汇要求的比较
背诵GRE词汇的三大诀窍
4个方法让你快速背诵GRE词汇
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |