首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
What produces a waterproof super glue, acts like a vacuum cleaner, and even teaches scientists about gene repair? The humble lit
What produces a waterproof super glue, acts like a vacuum cleaner, and even teaches scientists about gene repair? The humble lit
admin
2010-09-25
34
问题
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 chooses 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 comers, 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 10 000 shellfish to make just one gram of glue. So collecting 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?"
Scientists are not thinking of using mussels to produce the super glue mainly because of ______.
选项
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
答案
C
解析
推断题。由上可知:不过,科学家并没有打算利用贻贝本身来制作这种强力胶水,因为生产1克胶水就需要大约10 000个甲壳水生动物。故C项正确。
转载请注明原文地址:https://kaotiyun.com/show/5Bz7777K
0
大学英语六级
相关试题推荐
A、Youngpeopleusuallythinkthatoldwaysarenotacceptable.B、TheAmericangirlcan’tacceptwearingareddressatherweddi
A、Peopleshouldcontinuetoworkuntiltheyarequiteold.B、Peopleshouldearnalotofmoneybeforeretirement.C、Peopleshoul
AcrosstheUnitedStates,scientistsaremountingwhatmaybecomethemostinnovativeagriculturalresearchdrivesincethe1920
AcrosstheUnitedStates,scientistsaremountingwhatmaybecomethemostinnovativeagriculturalresearchdrivesincethe1920
A、Soil.B、Humanpopulation.C、Forest.D、Water.B细节考察题。从文章中看出有土壤,森林,水资源,动植物等方面,而没提及对人口造成的影响。
ScientistssaythewarmingoftheEarth’satmospherehasbeguntoaffectplantandanimallifearoundtheworld.Scientistsfrom
A、Planets.B、Themoon.C、Thesun.D、Gods.C细节辨别题文章介绍了solar和lunar两个词的含义由来,solar表示与太阳有关的,而lunar表示与月亮有关的。
A、£5.B、£30.C、£50.D、£55.B本题属于较难的数字题,要经过运算之后才能得山结论。综合男士所说的Ifyoujoinnowyoucanhavethefirstmonthfree和Themembershipfee
随机试题
对肠结核患者的护理措施不妥的是
下列属于建设工程施工风险中经济与管理风险的有()
诚信行为记录中,良好记录的公布期限一般为()。
下列选项中的机床属于金属切削类的有()。
关于出口应税消费品的税收政策,下列表述正确的是( )。
以下哪些情形的无效宣告请求不予受理?
下列选项中,属于免责条件的是()
针对新冠肺炎疫情带来的冲击,“危和机总是同生并存的,克服了危即是机”。习近平如是闸释危机转化之道。对于中国经济,他要求“坚持用全面、辩证、长远的眼光分析当前经济形势,努力在危机中育新机、于变局中开新局”。这给我们在哲学上的启示有
已知F(x)是f(x)的原函数,则
JamesMartin认为从结构化设计和分析来提高数据处理生产率的做法,收效甚微,以下哪些因素影响其效果Ⅰ.应用需求变化使系统改动很大,无法预料Ⅱ.数据格式的不一致,导致数据共享性差Ⅲ.没用高级数据库语言,没有良好的数据库设计Ⅳ.企业应用存在许多
最新回复
(
0
)