All mammals, except human beings, have angiogenesis factor in their bodies.A. Right B. Wro
All mammals, except human beings, have angiogenesis factor in their bodies.
A. Right
B. Wrong
C. Not mentioned
All mammals, except human beings, have angiogenesis factor in their bodies.
A. Right
B. Wrong
C. Not mentioned
All the mammals are mentioned as migrating ones EXCEPT ______.
A.caribou
B.fin whale
C.reindeer
D.Alaska fur seal
All mammals, except human beings, have angiogenesis factor in their bodies.
A.Right
B.Wrong
C.Not mentioned
All the mammals are mentioned as migrating ones EXCEPT ______
A.caribou
B.fin whale
C.reindeer
D.Alaska fur seal
According to the passage, young owlets eat everything EXCEPT ______.
A.other small birds
B.insects
C.small mammals
D.nuts and seeds
听力原文: Millions of years ago, whales lived on land and walked on four legs. Today, whales still have small bones that are the remains of their hind legs, but these bones can only be seen on the inside of the whale. No one knows why whales left the land to live in the water.
However, scientists can imagine that when the whales changed their environment, their bodies underwent a change—taking on a more fish-like appearance. This new form. offered less resistance to the water, enabling the whales to swim faster.
Despite their fish like form, whales are not fish. A whale will drown, just as a man will, if it stays under water too long. When a whale is under water, it closes its nostrils tightly and holds its breath. The air in its lungs becomes very hot and full of water vapor. When the whale rises to the surface and exhales, its hot breath produces a column of water vapor that rises high in the air. A man produces the same effect when he exhales warm air on a cold morning.
Whales are classified as mammals because they bear their young, rather than laying eggs, and because the mother whales give the babies milk. Like other mammals, whales have warm blood. Their blood stays at the same temperature, even when they move from hot to cold water. They keep warm in cold water because they have a thick layer of fat just under their skins. This fat is called blubber, and it is thicker on whales that spend their lives in cold water. Almost all land mammals, except man, have hair on their bodies to keep them warm, but whales, which have very few hairs, are kept warm by their fat.
How does a whale keep itself warm?
A.By its thick layer of fat under its skin.
B.By moving frequently in the water.
C.By adjusting its blood temperature.
D.By taking in hot air.
All the aquatic mammals sleep a lot.
A.Right
B.Wrong
C.Not mentioned
阅读材料,回答题。
When We Are Asleep
Everyone dreams, but some people never recall their dreams, or do so very rarely. Other people always wake up with vivid recollections (记忆 ) of their dreams, though they forget them very quickly. In an average night of eight hours&39;sleep, an average adult will dream for around one hundred minutes, probably having three to five dreams, each lasting from ten to thirty minutes.
Scientists can detect when someone is having a dream by using an instrument which measures the electrical waves in the brain. During dreaming, these waves move more quickly. Breathing and pulse rate also increase, and there are rapid eye movements under the lids, just as though the dreamer were really looking at moving objects. These signs of dreaming have been detected in all mammals (哺乳动物) studied, including dogs, monkeys, cats, and elephants, and also some birds and reptiles (爬行动物) .This period of sleep is called the "D" state for around 50% of their sleep; the period reduces to around 25% by the age of 10.
Dreams take the form. of stories, but they may be strange and with incidents not connected, which make little sense. Dreams are seldom without people in them and they are usually about people we know. One estimate says that two-thirds of the "cast" of our dream dramas are friends and relations. Vision seems an essential part of dreams, except for people blind from birth. Sound and touch senses are also often aroused, but smell and taste are not frequently involved. In "normal" dreams, the dreamer may be taking part, or be only an observer. But he or she cannot control what happens in the dream.
However, the dreamer does have control over one type of dream. This type of dream is called a "lucid"(清醒的) dream. Not everyone is a lucid dreamer. Some people are occasional lucid dreamers. Others can dream lucidly more or less all the time. In a lucid dream, the dreamer knows that he is dreaming.
Some people dream but cannot remember their dreams. 查看材料
A.Right
B.Wrong
C.Not mentioned
This suggests that these "top dogs" of the ocean are【C6】______and multiplying.【C7】______, such has not been the case, at ieast not for the last 150 years. Trouble has closed in【C8】______these mammals in the form. of equally warm-blooded and even more【C9】______adaptable predators, humans. At sea,【C10】______on land, humans have now【C11】______themselves on the top of the whole great pyramid of life, and【C12】______have caused serious problems for the mammals of the sea, There is a simple【C13】______for this.
【C14】______mammals have the misfortune to be swimming aggregates of【C15】______that humans want: fur, oil and meat. Even so, they might not be so【C16】______to human depredation if they did not, like humans,【C17】______so slowly.
Every year humans【C18】______more than 50 million tons of fish from the oceans without critically depleting the population of any【C19】______. But the slowbreeding mammals of the sea have been all but wiped out by humans【C20】______satisfy their wants and whims.
【C1】
A.involved
B.evolved
C.evoked
D.exceeded
When We Are Asleep
Everyone dreams, but some people never recall their dreams, or do so very rarely. Other people always wake up with vivid recollections (记忆) of their dreams, though they forget them very quickly. In an average night of eight hours' sleep, an average adult will dream for around one hundred minutes, probably having three to five dreams, each lasting from ten to thirty minutes.
Scientists can detect when someone is having a dream by using an instrument which measures the electrical waves in the brain. During dreaming, these waves move more quickly. Breathing and pulse rate also increase, and there are rapid eye movements under the lids, just as though the dreamer were really looking at moving objects. These signs of dreaming have been detected in all mammals (哺乳动物) studied, including dogs, monkeys, cats, and elephants, and also some birds and reptiles (爬行动物). This period of sleep is called the “D” state for around 50% of their sleep; the period reduces to around 25% by the age of 10.
Dreams take the form. of stories, but they may be strange and with incidents not connected, which make little sense. Dreams are seldom without people in them and they are usually about people we know. One estimate says that two-thirds of the “cast” of our dream dramas are friends and relations. Vision seems an essential part of dreams, except for people blind from birth. Sound and touch are senses also often aroused, but smell and taste are not frequently involved. In “normal” dreams, the dreamer may be taking part, or be only an observer. But he or she cannot control what happens in the dream.
However, the dreamer does have control over one type of dream. This type of dream is called a “lucid”(清醒的) dream. Not everyone is a lucid dreamer. Some people are occasional lucid dreamers. Others can dream lucidly more or less all the time. In a lucid dream, the dreamer knows that he is dreaming.
Some people dream but cannot remember their dreams.
A.Right
B.Wrong
C.Not mentioned