英文书摘精选 What Is Spider Silk?蜘蛛丝是什么?
时间：2018-12-28 作者：英语课 分类：初学者听力文摘精选
What’s five times as strong as steel, twice as tough as Kevlar, and can be stretched over thirty percent in length without breaking? The answer is spider silk.
什么东西的强度是钢的5倍？什么东西的韧性是凯夫拉的2倍？什么东西能够拉长到自身长度的30%却不会断裂？答案是，蜘蛛丝。
Spiders make at least six different types of silk which they use for locomotion 1, protecting eggs, wrapping prey 2, and gluing pieces of web together. Silk is not only strong, it’s biodegradable and produced at low temperatures and pressures, unlike many man made polymer fibers 3.
蜘蛛能生产至少6种不同类型的蛛丝用以移动、护卵、捕食和结网。蛛丝不仅结实，而且在低温低压下可生物降解和再生。这有别于许多人造纤维。
Why don’t we use spider silk to make things?
为什么我们不利用蜘蛛丝来制作产品呢？
Unlike silk worms, spiders can’t produce much silk at a time. It took eighty weavers 5 and a million golden orb 6 spiders five years to make a spider silk rug a little over twelve feet square.
蜘蛛无法像蚕那样在短时间内产生大量的丝。制作12平方英尺多点的蛛网地毯，需要80名织工，使用100万只金球蜘蛛，花费5年时间才能完成。
Scientists decided 7 to work on the silk quantity problem. And, no, they didn’t create giant spiders. First, they identified soft and crystalline components 8 in the silk protein sequences that make it both stretchy and strong. Once they identified these elements, they located the gene 9 that codes for spider silk.
科学家们决定研究蛛丝的数量问题。当然他们不会去创造巨型蜘蛛。首先，他们在蛛网蛋白序列中识别出使蛛网具备延展性和强韧性的柔软又透明的成份。一旦科学家们成功识别出这些成份，他们就能锁定形成蛛网的基因。
Genes 10
基因
With the gene in hand, scientists decided to use a common intestinal 11 bacteria named Escherichia coli to help them. They inserted the spider gene into the bacteria. Because the protein was large, they had to do some metabolic 12 engineering to enable the bacteria to produce it.
基因到手后，科学家们决定使用一种普遍的肠道细菌——大肠杆菌——作为辅助。他们要把蜘蛛基因嵌入大肠杆菌。不过蜘蛛的蛋白很大，所以科学家们需要做一些代谢工程使得大肠杆菌能够生产蜘蛛蛋白。
In the end, they made spider silk, but it wasn’t as fine as the real thing. That’s because spiders enhance the uniformity of their silk as they pull it from their spinnerets.
最后，大肠杆菌产出蛛网，但其质量不如真正的蛛丝那么理想。原因在于蜘蛛是从吐丝器官里把蛛丝拉出来的，这加强了蛛丝的均匀性。
The pulling process wasn’t replicated 13 in the lab until scientists developed a device to mimic 14 the fiber 4-pulling step. They have now created a thread rivaling natural silk.
在科学家们开发出一种模拟拉出蛛丝的设备之前，这种拉丝过程无法在实验室里复制。不过科学家们现已创造出一种与织线媲美的天然丝。
This great fiber could soon be used for violin strings 15 as well as bullet proof vests.
这种优质的纤维预计很快就能用于小提琴琴弦或者防弹背心上了。
- By land,air or sea,birds are masters of locomotion.无论是通过陆地，飞越空中还是穿过海洋，鸟应算是运动能手了。
- Food sources also elicit oriented locomotion and recognition behavior patterns in most insects.食物源也引诱大多数昆虫定向迁移和识别行为。
- Stronger animals prey on weaker ones.弱肉强食。
- The lion was hunting for its prey.狮子在寻找猎物。
- Thesolution of collagen-PVA was wet spined with the sodium sulfate as coagulant and collagen-PVA composite fibers were prepared. 在此基础上，以硫酸钠为凝固剂，对胶原-PVA共混溶液进行湿法纺丝，制备了胶原-PVA复合纤维。
- Sympathetic fibers are distributed to all regions of the heart. 交感神经纤维分布于心脏的所有部分。
- The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
- The material must be free of fiber clumps.这种材料必须无纤维块。
- The Navajo are noted as stockbreeders and skilled weavers, potters, and silversmiths. 纳瓦霍人以豢养家禽，技术熟练的纺织者，制陶者和银匠而著名。
- They made out they were weavers. 他们假装是织布工人。
- The blue heaven,holding its one golden orb,poured down a crystal wash of warm light.蓝蓝的天空托着金色的太阳，洒下一片水晶般明亮温暖的光辉。
- It is an emanation from the distant orb of immortal light.它是从远处那个发出不灭之光的天体上放射出来的。
- This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
- There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。
- the components of a machine 机器部件
- Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。
- A single gene may have many effects.单一基因可能具有很多种效应。
- The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
- You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
- Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
- A few other conditions are in high intestinal obstruction. 其它少数情况是高位肠梗阻。 来自辞典例句
- This complication has occasionally occurred following the use of intestinal antiseptics. 这种并发症偶而发生在使用肠道抗菌剂上。 来自辞典例句
- Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。
- A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。
- Later outplant the seedlings in a replicated permanent test plantation. 以后苗木出圃栽植成重复的永久性试验林。
- The phage has replicated and the donor cells have lysed. 噬菌体已复制和给体细胞已发生裂解。