What Is Biology
The science of biology is, broadly speaking , the study of living things.It draws on chemistry and physics for its foundation and applies these basic physical laws to living things.Because there are many kinds of living things, there are many special areas of study in biology.Practical biology—like medicine, crop science, plant breeding, and wildlife management –is balanced by more theoretical biology—such as medical microbiological physiology, photosynthetic biochemistry, plant taxonomy, and animal behavior (ethology).There is also just plain fun biology like insect collecting and bird watching.Specifically, biology is a science that deals with living things and how they interact with all of the things around them.Biology was defined as the science that deals with livings.But what does it mean to be alive? You would think that a biology textbook could answer this question very easily.However, this question is more than just a theoretical one, since it has become neceary in recent years to construct some legal definitions of what life is and especially when it begins and ends.The legal definition of death is important since it may determine whether or not a person will receive life insurance benefits or if body parts may be used in transplants.In case of heart transplants, the person donating the heart may be legally ― dead ‖, but the heart certainly isn’t since it can be removed while it still has ―life‖.In other words ,there are different kinds of death.There is the death of the whole living unit and the death of each cell within the living unit.A person actually ―dies‖ before every cell has died.Death ,then, is the absence of life, but that still doesn’t tell us what life is.At this point, we won’t try to define life but will describe some of the basic characteristics of living things.
生物科学，广泛的说，即是对活的生物的研究。它利用化学和物理学为基础并将这些自然法则应用到生物中。.由于生物多样性的存在，生物学中有很多特殊的研究领域。一些实用生物学，例如医学，作物学，植物育种学和野生动物管理学，已经同很多例如医学微生物生理学，光合生物化学，植物分类法，动物行为学的理论生物学形成均势。还有一些仅仅由兴趣产生的简单的生物学，像昆虫收集和观察鸟类。具体来讲，生物学是研究生物以及生物与生物及生物与环境之间相互作用的科学。
生物学被定义为研究活的生物体。那就意味着必须得是活的物体么？你可能会认为一本生物学课本可以很简单的回答这个问题。然而，最近几年，在创立一些合法的定义例如什么是生命，特别是何时为生何时为死方面，这个问题已经成为了必需的部分，因此，它已经不仅仅是理论问题了。法律对死的定义很重要，它将决定一个人是否能够获得人寿保险的赔偿或者一个身体器官是否可以用于移植。以心脏移植为例，捐献心脏的人必须是法律上的死亡，但是既然能够移植，心脏肯定不是死的，所以它还是“活”的。换句话说，死亡可以有很多种。有些是所有的生命单位都死亡，还有生命单元中的每个细胞都死亡。一个人的其实在所有的细胞都死亡之前已经死了。死亡，生命的缺失，但仍没有告诉我们什么是生。因此，我们不会试图定义什么是生，但会描述活的生命的一些基本特征。
The Value of Biology
To a great extent, we owe our current high standard of living to biological advances in two areas: food production and disease control.Plant and animal breeders have developed plants and animals that provide better sources of food than the original varieties.One of the best examples of this is the various changes that have occurred in corn.Corn is a gra that produces its seed on a cob.The original corn plant had very small ears that were perhaps only three or four centimeters long.Through selective breeding, varieties of corn with much larger ears and more seeds per cob have been produced.This has increased the yield greatly.In addition, the corn plant has been adapted to produce other kinds of corn, like sweet corn and popcorn..Corn is not an isolated example.Improvement in yield have been brought about in wheat, rice oats, and other cereal grains.The improvements in the plants, along with changed farming practices(also brought about through biological experimentation),have led to greatly increased production of food.Animal breeders have also had great succees.The pig, chicken, and cow of today are much different animals from those available even one hundred years ago.Chickens lay more eggs, dairy cows give more milk, and beef cattle grow faster.All of these improvements raise our standard of living.One interesting example is the change in the kinds of hogs that are raised At one time, farmers wanted pigs that were fatty.The fat could be made into lard, soap, and a variety of other useful products.As the demand for the fat products of pigs began to decline, animal breeders began to develop pigs that gave a high yield of meat and relatively little fat.Today, plant and animal breeders can produce plants and animals almost to specifications.
在很大程度上，我们应把当前我们高标准生活中先进的生物领域规为两大领域：食品生产和疾病治理。动植物繁殖者们已经开始培育新的动植物了，这些新培育的动植物可以比原来的种类更好的提供食物来源。最好的一个例子就是发生在玉米上的各种各样的变化。玉米是一种禾草，它的产物是种子，长在玉米穗轴上。原始玉米的穗很小，大概只有3到4厘米长。
通过有选择性的繁殖，各种各样的玉米有了更长的穗和每个穗轴上产出了更多的种子。这使得产量有了很大的提高。另外，这种玉米已经应用于其他种类的玉米产品上了，比如甜玉米和爆米花。
玉米不是唯一的例子。在小麦，大米，燕麦和其它谷类作物上都提高了产量。在改进植物的同时，也要改变农作方式（当然，也带来了一些生物学上的实验），就会导致食物的增产。
动物饲养者们同样也取得了很大的成功。今天的猪，鸡和牛在一些可利用方面要与一百年前的有所不同。鸡会产更多的蛋。奶牛会产出更多的牛奶，肉牛会长的更快。所有的这些进步，都会提高我们的生活水平。一个有趣的例子就是在各种猪的身上发生了一些改变，那就是增加了它们的数量。同时，农民希望猪能胖一些。脂肪可以制成猪油，肥皂和其它一些有用的产品。当猪脂肪产品的需求量开始下降时，动物饲养者就开始培育一种猪，这种猪有较高的瘦肉产量和较少的肥肉。今天，动植物的培育者们可以培育出具有相同标准的动植物产品。
Much of the improvement in food production has resulted from the control of plants and animals that compete with or eat the organisms we use as food.Control of insects and fungi that weaken plants and reduce yields is as important as the invention of new varieties of plants.Since these are ―living‖ pests, biologists have been involved in the study of them also.There has been fantastic progre in the area of health and disease control.Many diseases such as polio, whooping cough, measles, and mumps can be easily controlled by vaccinations or ―shots‖.Unfortunately, the vaccines have worked so well that some people no longer worry about getting their shots, and some of these diseases are reappearing.These diseases have not been eliminated, and people who are not protected by vaccinations are still susceptible to them.The understanding of how the human body works has led to treatments that can control diseases such as diabetes, high blood preure, and even some kinds of cancer.Paradoxically, these advances contribute to a major biological problem: the increasing size of the human population.
大部分的食品生产都是通过控制我们食用的动植物原料的质量来得到提高的。发明一个可控制那些能够削弱植物和减少产量的昆虫和病菌的新物种也是非常重要的。自从这些“生活”病虫害出现之后，生物学家对它们进行了深入的研究。
这在健康和疾病控制方面是一个非常积极的工程。许多疾病如小儿麻痹症、百日咳、麻疹以及流行性腮腺炎等都可以通过接种疫苗来得到控制。但不幸的是，由于疫苗的效果良好使得许多人不再重视疫苗的注射，而使得许多疾病又再次出现。那些没有被消除的病毒对于一些没有被疫苗所保护的人来说还是比较容易感染上的。
通过理解人体是如何导致疾病的如糖尿病、高血压以及各种癌症等，就知道该如何控制它们的发生了。奇怪的是，这些研究进展有助于我们的一个主要的生物学问题：人口的增长问题。
Biological problems Now that you have seen some progre that can be credited to biologists, we will look at some of the problems that have been created by improperly used biological principles.For example, the drive to preserve nature has in some cases resulted in conflicting goals.Many of our western forests have been preserved as parks.In order to preserve the trees, fire was not allowed in these forests.The lack of fire led to a dangerous buildup of debris, which could result in abnormally devastating fires.Before our involvement, periodic, natural fires cleaned out the debris and helped to preserve the trees from more intense fires.These fires also eliminated some undesirable species of trees.As a result, the U.S.Park Service changed its policy on fires in parks and began to allow naturally caused fires to burn themselves out.This caused considerable debate among parks managers, forest interests, and the public.A whole generation of people had grown up with the idea that all forest fires were bad.During the extremely dry summer of 1988, several huge fires burned in Yellowstone National Park and other parks in the west.As a result of these fires, the Park Service has modified its policy and will take measures to control fires if conditions are such that they may alter huge portions of the park ecosystem.
既然我们从生物学家的努力中获得了一些进步，那么我们也能看到一些因为生物学原理被不合理应用而引发的问题。例如开车去保护环境在某些情况下反倒会导致截然相反的结果。西部的很多森林都被作为公园而保护起来。火的缺乏会导致能够引起毁灭性火灾的森林残骸的积累。在我们参与之前自然的火灾可以清理掉这些残骸，从而避免树木遭到更严重火灾的破坏。火灾也可以烧掉一些不良的树种。所以，美国国家公园管理局修改了关于公园火灾方面的政策，开始允许自然地火灾烧掉他们自己。这个做法引起了公园管理者在森林利益和公众利益方面的激烈争论。整整一代人都是伴随着森林火灾是有害的这个想法长大的。在1988年极其干燥的夏季期间，西部地区包括美国黄石国家公园在内的一些公园都发生了数起大型的火灾。因为这些火灾，公园管理者修改了关于火灾的政策，如果火灾情况可能会改变公园的大部分生态系统那么他们会采取措施去控制这些火灾。
A second major biological mistake has been the introduction into some countries of exotic (foreign) species of plants and animals .In North America, this has had disastrous consequences in a number of cases.Both the American chestnut and the American elm have been nearly eliminated by diseases that were introduced by accident.Other things have been introduced on purpose through shortsightedne or a total lack of understanding about biology.The starling and the English (house) sparrow were both introduced into this country by people who thought that they were doing good.Both of these birds have multiplied greatly and replaced some of the birds that were native to the United States.The gypsy moth is also an introduced species; they were brought to the United States by manufacturers in hopes of increasing silk production.When the scheme fell short of their goal, and moths were accidentally set free, the moths quickly took advantage of their new environment by feeding on desirable ornamental plants and crops.Even with these examples before us, there are still people who try to sneak exotic plants and animals into the country without thinking about the poible consequences.
另一个最主要的生物失败在于向外国引进植物及动物物种。在北美地区，这种现象已经在很多事件中带来了灾难性的影响。由于错误的引进，美国板栗和榆树已经濒临消失。其他的引进也是由于目光短浅及生物学知识的匮乏而发生。椋鸟和英国的麻雀也被那些自认为做好事的人引进到这个国家。这两种鸟类大量繁殖取代了美国一些本土种类的鸟。吉普赛蛾也是被引进的物种之一；它们被那些希望制造丝质产品的生产商引进到美国。当他们的计划落空时，他们的目标，和意外释放的飞蛾，迅速利用新环境的喂养对理想的观赏植物和农作物。即使有了这些，我们之前，仍然有人试图潜入外来植物和动物进入该国而没有考虑可能产生的后果。
Another major area where problems have been caused by biological advances is in the area of bioethics.In many ways technological advances have presented us with a series of ethical situations that we have not been able to resolve satisfactorily. Major advances in health care have allowed persons to live who would have died a generation earlier.Many of the techniques and machines that allow us to preserve and extend life are extremely expensive and are therefore unavailable to most citizens of the world.Furthermore, many people in the world are lacking even the most basic health care, while the rich nations of the world spend money on cosmetic surgery and keep comatose patients alive with aistance of machines.
另一个因生物学进展而引起问题的主要领域是生物伦理学。在许多方面，技术的进步已经给我们带来了一系列在道德范畴我们一直无法圆满解决的问题。卫生保健中的重大进展，已允许个人用生物技术来延长自己的生命。让我们保持和延长寿命的技术和机器，很多都是极其昂贵，因此世界大多数公民无法使用。此外，在世界上还有许多人甚至缺乏最基本的卫生保健，而有些国家却在整容手术上和维持植物人的机能的仪器上花费着大量的财力。
