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Passage Five What produces a waterproof super glue, acts like a vacuum cleaner, and even teaches scientists about gene repair The humble little shellfish known as the mussel (贻贝)。 Mussels are found worldwide. Some live in the sea. Others inhabit freshwater streams and lakes. When you try to move a mussel from a rock, you will discover what an incredibly firm grip it has- a necessity if the mussel is to resist the sharp grab of a hungry seabird or the pounding waves of the sea. How does it manage to cling so tight When it choose a place to set up home, it pokes its tongue-shaped foot out of its shell and presses it against a solid surface. Special glands give off a fluid mixture of proteins into a channel that runs the length of the foot. The liquid quickly hardens into a fine, elastic thread about an inch long. Then a tiny pad-like structure at the end of this thread gives off some natural glue-like substance, the mussel lifts its foot, and anchor line number one is complete. These strategically placed threads form a bundle, which ties the mussel to its new home in much the same way that ropes hold down a tent. The whole procedure takes only three or four minutes. Imagine having a very strong glue that is non-toxic and so flexible that it can penetrate the tiniest holes and corners, sticking to any surface, even under water. Shipbuilders would welcome it for repairing vessels without the expense of dry-docking them. Auto-body workers would like a really waterproof paint that keeps the rust out. Surgeons would value a safe glue to join broken bones and to close wounds... The list of possible uses appears endless. However, scientists are not thinking of using the mussels themselves to produce this super glue. It would take some l0.000 shellfish to make just one gram of glue. So collection enough mussels to supply the world’s demand for super glue would wipe out the mussel population, many species of which are already endangered. Instead, American researchers have isolated and cloned the genes for five mussel glue proteins, and they are about to mass-produce them in the laboratory. However, the mussel is still one jump ahead. Only the mussel instinctively knows the exact blend of proteins needed for each kind of surface. Molecular biologist Frank Roberto has asked admiringly: "How are you ever going to imitate that" To tie itself safely to a new home, a mussel must ______
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Passage One My surprise over the past few winters has been the personality transformation my parents go through around mid-December as they change from Dad and Mom into Grandpa and Grandma. Yes, they become grandparents and are completely different from the people I know the other eleven and a half months of the year. The first sign of my parents’ change is the delight they take in visiting toy and children’s clothing stores. These two people, who usually dislike anything having to do with shopping malls, become crazy consumers. While they tell me to budget my money and shop wisely, they are buying up every doll and dump truck in sight. And this is only the beginning of the holidays! When my brother’s children arrive, Grandpa and Grandma come into full form. First they throw out all ideas about a balanced diet for the grandkids. While we were raised in a house where everyone had to take two bites of corn, beets (甜菜) , or liver (foods that appeared quite often on our table despite constant complaining), the grandchildren never have to eat anything that does not appeal to them. Grandma carries chocolate in her pockets to bribe (贿赂) the littlest ones into following her around the house, while Grandpa offers "surprises" of candy and cake to them all day long. Boxes of chocolate-pie disappear while the whole-wheat bread get hard and stale. The kids love all the sweets, and when the sugar raises their energy levels, Grandma and Grandpa can always decide to leave and do a bit more shopping or go to bed while my brother and sister-in-law try to deal with their highly active kids. Once the grandchildren have arrived, Grandma and Grandpa also seem to forget all of the responsibility lectures I so often hear in my daily life. If Mickey screams at his sister during dinner, he is "developing his own personality"; if Nancy breaks Grandma’s mirror, she is "just a curious child". But, if I track mud into the house while helping to unload groceries, I become "careless"; if I scold one of the grandkids for tearing pages out of my textbook, I am" impatient". If Paula talks back to her mother, Grandma and Grandpa smile at her spirit. If I say one word about all of this excessive love, Mom and Dad reappear to have a talk with me about petty jealousies. It can be inferred from the passage that when the author was a child, he ______
Passage One My surprise over the past few winters has been the personality transformation my parents go through around mid-December as they change from Dad and Mom into Grandpa and Grandma. Yes, they become grandparents and are completely different from the people I know the other eleven and a half months of the year. The first sign of my parents’ change is the delight they take in visiting toy and children’s clothing stores. These two people, who usually dislike anything having to do with shopping malls, become crazy consumers. While they tell me to budget my money and shop wisely, they are buying up every doll and dump truck in sight. And this is only the beginning of the holidays! When my brother’s children arrive, Grandpa and Grandma come into full form. First they throw out all ideas about a balanced diet for the grandkids. While we were raised in a house where everyone had to take two bites of corn, beets (甜菜) , or liver (foods that appeared quite often on our table despite constant complaining), the grandchildren never have to eat anything that does not appeal to them. Grandma carries chocolate in her pockets to bribe (贿赂) the littlest ones into following her around the house, while Grandpa offers "surprises" of candy and cake to them all day long. Boxes of chocolate-pie disappear while the whole-wheat bread get hard and stale. The kids love all the sweets, and when the sugar raises their energy levels, Grandma and Grandpa can always decide to leave and do a bit more shopping or go to bed while my brother and sister-in-law try to deal with their highly active kids. Once the grandchildren have arrived, Grandma and Grandpa also seem to forget all of the responsibility lectures I so often hear in my daily life. If Mickey screams at his sister during dinner, he is "developing his own personality"; if Nancy breaks Grandma’s mirror, she is "just a curious child". But, if I track mud into the house while helping to unload groceries, I become "careless"; if I scold one of the grandkids for tearing pages out of my textbook, I am" impatient". If Paula talks back to her mother, Grandma and Grandpa smile at her spirit. If I say one word about all of this excessive love, Mom and Dad reappear to have a talk with me about petty jealousies. As regards his parents’ shopping for the grandchildren, the author ______
In recent years a new farming revolution has begun, one that involves the (61) of life at a fundamental level--the gene. The study of genetics has (62) a new industry called biotechnology. As the name suggests, It (63) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (64) seeds that give a high yield, that (65) diseases, drought and frost, and that reduce the need for (66) chemicals. If such goals could be achieved, it would be most (67) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (68) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (69) usually involves taking genes from one species and inserting them into another (70) to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (71) from an artic fish, and inserting it into a potato or strawberry to make it frost-resistant. (72) , then, biotechnology allows humans to (73) the genetic wails that separate species. Like the green revolution, (74) some call the gene revolution contributes to the problem of genetic uniformity--some say even more so (75) geneticists can employ techniques such as cloning and (76) culture (培养), processes that produce perfectly (77) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (78) , such as the effects that they may have on us and the environment. "We are flying blindly into a new (79) of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (80) " said science writer Jeremy Rifkin.
Passage Two Children live in a world in which science has tremendous importance. During their lifetimes it will affect them more and more. In time, many of them will work at jobs that depend heavily on science--for example, concerning energy sources, pollution control, highway safety, wilderness conservation, and population growth. As taxpayers they will pay for scientific research and exploration. And, as consumers, they will be bombarded (受到轰击) by advertising, much of which is said to be based on science. Therefore, it is important that children, the citizens of the future, become functionally acquainted with science--with the process and spirit of science, as well as with its facts and principles. Fortunately, science has a natural appeal for youngsters. They can relate it to so many things that they encounter--flashlights, tools, echoes, and rainbows. Besides; science is an excellent medium for teaching far more than content. It can help pupils learn to think logically, to organize and analyse ideas. It can provide practice in communication skills and mathematics. In fact, there is no area of the curriculum to which science cannot contribute, whether it is geography, history, language arts, music, or art! Above all, good science teaching leads to what might be called a "scientific attitude". Those who possess it seek answers through observing, experimenting, and reasoning, rather than blindly accepting the pronouncements of others. They weigh evidence carefully and reach conclusions with caution. While respecting the opinions of others, they expect honesty, accuracy, and objectivity and are on guard against hasty judgments and sweeping generalizations. All children should be developing this approach to solving problems, but it cannot be expected to appear automatically with the mere acquisition of information. Continual practice, through guided participation, is needed. In the passage the writer seems to ______
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