同等学力英语每日练习:2017年1月16日
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 10000 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？”
56. A mussel grips a hard surface very firmly to （ ）.
A. seal itself from being damaged by sea water
B. produce the waterproof super glue
C. protect itself from being blown away by strong wind
D. protect itself from being the food of other animals
57. The waterproof super glue originates in （ ）.
A. the mussel’s tongue-shaped foot
B. some glands in the mussel’s body
C. the thread given off by the mussel
D. the channel of the mussel’s foot
58. To tie itself safely to a new home，a mussel must （ ）.
A. produce a thread to anchor to the hard surface
B. draw air and water from its pad-like structure
C. hold down a tent as human beings do
D. place many anchor lines strategically
59. Scientists are not thinking of using mussels to produce the super glue mainly because of （ ）.
A. the possible mass-production of the super glue
B. their concern about the cost of collecting mussels
C. their concern about the extinction of the species
D. the world’s limited demand for the super glue
60. The main idea of this passage is that （ ）.
A. mussels can be used to produce super glue
B. mussels are much smarter than we think
C. it is important to protect mussels
D. mussels have an amazing power useful to man
译文：
是什么制成了防水强力胶水，就像真空吸尘器一样，甚至教会了科学家有关基因修复的知识？这个低等的小甲壳水生动物，就是所谓的贻贝！
贻贝可以在全世界找到。一些贻贝生长在海洋里，其他贻贝寄居在淡水溪流和湖泊中。当你试图从块岩石上移动一个贻贝时，你会发现，贻贝与岩石之间的结合如此牢固让人难以置信——这是必要的，如果贻贝想要抵抗一只饥饿海鸟的凶猛捕食，或者抵抗海浪的冲刷。贻贝是如何粘贴得那么紧的呢？当贻贝选择一个地方建造自己的家时，它就会将它的像舌头一样的脚伸出它的贝壳外，把脚紧紧按压在一个固体的表面上。特殊的腺组织分泌出一种液体的蛋白质混合物，这种混合物流进一个导管，这个导管顺着脚延展。这种液体迅速硬化成为一根细的、有弹性的长约一英寸的细丝。接着，这根细丝末端的一个微小垫状组织分泌出某种天然的胶状物质，贻贝会抬起脚，第一个固定线路就完成了。战略性地放置这些细线形成了束线，这就将贻贝与它的新家牢牢地连接在一起，这种方法与人们用绳子搭建帐篷的方法极为相似。整个过程只需三到四分钟。
想象一下拥有这种强力无毒胶水，它如此柔韧，以至于可以渗透进最小的洞和角落，粘到任何表面上，甚至在水中。造船工程师们会喜欢它，因为它不必支付昂贵的干燥船只的费用就可以修复船只。车身工人也会喜欢真正的防水涂料，使车身不生锈。外科医生也会非常喜欢这种安全黏合剂，以便连接断裂的骨头，缝合伤口……这种胶水的可能用途的清单似乎没有止境。
不过，科学家并没有考虑利用贻贝本身来生产这种强力胶水。只是生产1克胶水就需要大约10000个甲壳水生动物。因此，收集足够的贻贝来满足全球对强力胶水的需求会导致贻贝的灭绝，而且许多贻贝物种已经处于灭绝危险了。于是，美国的研究人员分离了五种贻贝蛋白质并且克隆出了它们的基因，他们将在实验室大量培育这些基因。然而，贻贝总是领先一步。只有贻贝本能地知道每种表面所需的蛋白质的精确混合。分子生物学家弗兰克·罗伯特赞赏地问道，“你们打算如何去模仿它呢？”
答案解析：
56.【正确答案】D
【考点类型】细节判断
【解析过程】贻贝抓住坚硬的表面，目的是
A. 保护自己不被海水伤害
B. 产生可以防水的胶水
C. 保护自身不被大风吹走
D. 保护自身不要成为其他动物的食物
线索：文章的第2段提到“a necessity if the mussel is to resist the sharp grab of a hungry seabird or the pounding waves of the sea.”表明D为正确答案。B选项不正确，因为生产超级胶水是贻贝抓住坚硬表面的手段而不是目的。
【考点提示】细节判断题做题的步骤：仔细审题干——返回原文找线索——根据线索和选项对照——得出正确答案。
57.【正确答案】B
【考点类型】细节判断
【解析过程】防水的超级胶水来自
A. 贻贝舌型的触角
B. 贻贝身体里的一些腺体
C. 贻贝分泌出去的线体
D. 贻贝触角的通道
线索：文章的第2段提到“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.”表明B为正确答案。C选项在文章中也提到了，但是题干说的是最初来自哪里，所以B 是正确答案。
【考点提示】细节判断题一定要细心，细心，再细心。这是唯一可以保证100%正确的做题方法。
58.【正确答案】D
【考点类型】细节判断
【解析过程】为了把它自身安全地固定在一个新家，贻贝必须
A. 产生一个线体稳固在坚硬的表面
B. 从它的类似吸盘的结构中吸入空气和水
C. 像人类一样支个帐篷
D. 战略性地放置许多如锚的线体
线索：文章的第1段提到“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.”表明D为正确答案。选项C在原文中提到了，但原文中仅仅是一个比喻的例证，不是贻贝固定新家的具体方法。
【考点提示】科普文章的语言一般是比较晦涩难懂的，这就需要同学们去适当地读一些中英文的科普常识，了解一些相关的背景知识。
59. 【正确答案】C
【考点类型】因果关系细节
【解析过程】科学家们不打算使用贻贝去生产超级胶水，主要是因为
A. 可能大规模生产超级胶水
B. 他们对于收集贻贝成本的担心
C. 他们对于这种物种灭绝的担心
D. 全世界对于超级胶水的有限的需求
线索：文章的第4段提到“It would take some 10,000 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.”表明C为正确答案。
【考点提示】因果关系题一般是有明显的线索词如because，for等，但是有些文章的内容也没有这些线索词，这就要求同学们一定要认真地阅读文章，把握句子之间的逻辑关系。
60.【正确答案】D
【考点类型】主旨推断
【解析过程】文章的主旨是
A. 贻贝能够被用于制作超级胶水
B. 贻贝是要比我们认为的更聪明
C. 保护贻贝是非常重要的
D. 贻贝对于人类有一个惊人的力量
线索：从整篇文章的中心把握，贻贝的这种产生超级胶水的能力是非常令人惊讶的，而且人类还无法复制。所以D是最好的选项。A和原文的最后一段表达的内容相反，而且它本身也不能成为文章的中心。
