4.9 生活所需能源
章节大纲
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Mush!
::乱七八糟的!These beautiful sled dogs are a metabolic marvel. While running up to 100 miles a day, they will each consume and burn about 12 thousand calories — about 240 calories per pound per day, which is the equivalent of about 24 Big Macs! A human endurance athlete, in contrast, typically burns only about 100 calories per pound each day. Scientists are intrigued by the amazing metabolism of sled dogs, although they still haven't determined how they use up so much energy . But one thing is certain: all living things need energy for everything they do, whether it's running a race or blinking an eye. In fact, every of your body constantly needs energy just to carry out basic life processes. You probably know that you get energy from the food you eat, but where does food come from? How does it come to contain energy? And how do your cells get the energy from food?
::这些美丽的雪橇狗是一个新陈代谢的奇迹。 它们每天消耗和燃烧大约12,000卡路里 — — 每磅约240卡路里,相当于每天24个大麦! 相比之下,人类耐力运动员通常每天只燃烧大约100卡路里。 科学家们对雪橇狗惊人的新陈代谢感兴趣,尽管他们还没有确定它们如何使用这么多能量。 但有一点是肯定的:所有生物都需要能源,不管它们做什么,不管是在赛跑还是眨眼。事实上,你们每个人不断需要能源来完成基本的生活过程。你可能知道,你从食物中获取能量,但食物来自何处? 科学家们如何从食物中获取能量呢? 细胞如何从食物中获取能量呢?What Is Energy?
::什么是能源?In the scientific world, energy is defined as the ability to do work. You can often see energy at work in living things — a flies through the air, a firefly glows in the dark, a dog wags its tail. These are obvious ways that living things use energy, but living things constantly use energy in less obvious ways, as well.
::在科学世界中,能源的定义是工作能力。你常常可以看到在生物中工作时的能量 — — 苍蝇在空气中,萤火虫在黑暗中发光,狗在尾巴中晃动。 这些都是生活事物使用能源的明显方式,但生活事物也经常以不太明显的方式使用能源。Why Living Things Need Energy
::生活为何需要能源Inside every cell of all living things, energy is needed to carry out life processes. Energy is required to break down and build up molecules, and to transport many molecules across plasma membranes. All of life’s work needs energy. A lot of energy is also simply lost to the environment as heat. The story of life is a story of — its capture, its change of form, its use for work, and its loss as heat. Energy (unlike matter) cannot be recycled, so organisms require a constant input of energy. Life runs on chemical energy. Where do living organisms get this chemical energy?
::所有生物的每个细胞中,都需要能源来进行生命过程。能源需要用来分解和积累分子,并将许多分子传送到等离子膜中。生命的所有工作都需要能源。许多能源也只是作为热力被环境所丧失。生命的故事是一个故事——它被捕捉,其形式变化,它用于工作,以及它作为热力的丧失。能源(与物质不同)不能被回收,因此生物需要不断的能量投入。生命靠化学能量运行。生物生物在什么地方得到这种化学能量?How Organisms Get Energy
::生物体如何获得能源The chemical energy that organisms need comes from food. Food consists of organic molecules that store energy in their chemical bonds . In terms of obtaining food for energy, there are two types of organisms: autotrophs and heterotrophs .
::有机体需要的化学能量来自食物,食物由有机分子组成,它们将能量储存在化学链中,在获取能源所需的食物方面,有两种生物:自养和血化。Autotrophs
::自动自发Autotrophs are organisms that capture energy from nonliving sources and transfer that energy into the living part of the . They are also able to make their own food. Most autotrophs use the energy in sunlight to make food in the process of . Only certain organisms — such as plants, , and some — can make food through photosynthesis. Some photosynthetic organisms are shown in the figure .
::自养生物是指从非生物来源获取能量并将这种能量转移到生物部分的生物,它们也能够自己生产食物,大多数自养生物利用阳光中的能量制造食物,只有某些生物,如植物和某些生物,可以通过光合作用来制造食物,有些光合生物在图中显示了。
Photosynthetic autotrophs, which make food using the energy in sunlight, include (a) plants, (b) algae, and (c) certain bacteria.
::光合成自养养分使食物使用阳光下的能量,包括(a)植物、(b)藻类和(c)某些细菌。Autotrophs are also called . They produce food not only for themselves, but for all other living things (known as consumers), as well. This is why autotrophs form the basis of , such as the food chain shown .
::也被称为自发性。 它们不仅为自己生产食物,而且为所有其他生物(称为消费者)生产食物。 这就是为什么自发性形成食物链等基础的原因。
A food chain shows how energy and matter flow from producers to consumers. Matter is recycled, but energy must keep flowing into the system. Where does this energy come from? (Though the decomposers are shown as the final step in this food chain, these organisms decompose material from each step of the food chain. See the Ecology Concepts for additional information.)
::食物链显示了能源与物质如何从生产者流向消费者。 物质是再循环的, 但能源必须源源不断流入系统。 这种能源来自何处? (尽管分解者是食物链的最后一步, 这些有机体从食物链的每一步分解物质。 更多信息请参见生态概念 。 )Heterotrophs
::内分红Heterotrophs are living things that cannot make their own food. Instead, they get their food by consuming other organisms, which is why they are also called consumers . They may consume autotrophs or other heterotrophs. Heterotrophs include all and , as well as many single-celled organisms. In the figure , all of the organisms are consumers except for the grass. What do you think would happen to consumers if all producers were to vanish from Earth?
::血富症是无法自食其食的活物。相反,他们通过食用其他生物获得食物,这也是为什么他们也被称为消费者的原因。他们可能消费自发性或其他血富症。血富症包括所有生物和许多单细胞生物。在图表中,除了草以外,所有生物都是消费者。如果所有生产者都从地球消失,那么消费者会怎样呢?Energy Molecules: Glucose and ATP
::能量分子:甘蔗糖和ATPOrganisms mainly use two types of molecules for chemical energy: glucose and ATP . Both molecules are used as fuels throughout the living world. Both molecules are also key players in the process of photosynthesis.
::生物体主要使用两种分子来进行化学能源:葡萄糖和ATP,这两种分子在整个生物世界都用作燃料,这两种分子也是光合作用过程中的关键分子。Glucose
::葡萄糖Glucose is a simple with the chemical formula C 6 H 12 O 6 . It stores chemical energy in a concentrated, stable form. In your body, glucose is the form of energy that is carried in your and taken up by each of your trillions of cells. Glucose is the end product of photosynthesis, and it is the nearly universal food for life.
::甘蔗是化学方程式C6H12O6的简单易行。 它以集中、稳定的形式储存化学能量。 在你的身体里,甘蔗是由你携带的能量形式,由你每一万亿个细胞吸收。 甘蔗是光合作用的最终产物,也是几乎普遍的终身食物。ATP
::ATP 阿拉伯TPATP (adenosine triphosphate) is the energy-carrying molecule that cells use for energy. It is used for energy by all c ells in most cellular processes. ATP is made during the first half of photosynthesis and then used for energy during the second half of photosynthesis, when glucose is made. ATP releases energy when it gives up one of its three phosphate groups (P i ) and changes to ADP (adenosine diphosphate , which has two phosphate groups) , as shown in the figure . Thus, the breakdown of ATP into ADP + P i is a catabolic reaction that releases energy (exothermic). ATP is made from the combination of ADP and P i , an anabolic reaction that takes in energy (endothermic).
::ATP(乙酸三磷酸酯)是细胞用于能量的含有能量的分子,在大多数细胞过程中,所有细胞都将其用作能源。ATP是在光合作用前半期制作的,然后在光合作用后后半期,在制造葡萄糖时用于能源。ATP在放弃三种磷酸三组之一(Pi)和改变ADP(二磷酸二酯组,有两个磷酸二酯组)时释放出能量,如图所示。因此,ATP分解成ADP+Pi是一种释放能量(异温)的代谢反应。ATP是由ADP和Pi结合而成的,一种吸收能量(异温)的代谢反应。Why Organisms Need Both Glucose and ATP
::为何有机体既需要葡萄糖也需要ATPWhy do living things need glucose if ATP is the molecule that cells use for energy? Why don’t autotrophs just make ATP and be done with it? The answer is in the “packaging.” A molecule of glucose contains more chemical energy in a smaller “package” than a molecule of ATP. Glucose is also more stable than ATP. Therefore, glucose is better for storing and transporting energy. Glucose, however, is too powerful for cells to use. ATP, on the other hand, contains just the right amount of energy to power life processes within cells. For these reasons, both glucose and ATP are needed by living things.
::如果ATP是细胞用于能源的分子,那么生活的东西为什么需要葡萄糖呢?为什么ATP是细胞用于能源的分子呢?为什么ATP不是自发的,而是用ATP做成的?答案是“包装 ” 。 葡萄糖的分子在比ATP的分子更小的“包装”中含有更多的化学能量。 Glucose也比ATP更稳定。 因此,葡萄糖更适合储存和运输能源。 然而,Glucose对细胞来说太强大了,无法使用。 另一方面,ATP包含的只是细胞内动力生命过程的正确能量量。 出于这些原因,生物需要葡萄糖和ATP。How Energy Flows Through Living Things
::如何通过生命的能源流动The flow of energy through living organisms begins with photosynthesis. This process stores energy from sunlight in the chemical bonds of glucose. By breaking the chemical bonds in glucose, cells release the stored energy and make the ATP they need. The process in which glucose is broken down and ATP is made is called .
::活生物体的能量流动始于光合作用。 这一过程将阳光的能量储存在葡萄糖的化学链条中。 通过打破葡萄糖的化学链条,细胞释放了储存的能量,并使得它们需要ATP。 将葡萄糖分解和ATP制成的过程被称为 。Photosynthesis and cellular respiration are like two sides of the same coin. This is apparent in the figure . The products of one process are the reactants of the other. Together, the two processes store and release energy in living organisms. The two processes also work together to recycle oxygen in the Earth’s atmosphere .
::光合作用和细胞呼吸就像同一枚硬币的两面。这在图中显而易见。一个过程的产物是另一个过程的反反应物。两个过程共同储存和释放活生物体中的能量。 这两个过程还一起在地球大气层中回收氧气。
This diagram compares and contrasts photosynthesis and cellular respiration. It also shows how the two processes are related.
::该图比较和对比了光合作用和细胞呼吸,还显示了这两个过程之间的关系。Summary
::摘要-
Energy is the ability to do work.
It
is needed by all living things and every living cell to carry out life processes, such as breaking down and building up molecules, and transporting many molecules across cell membranes.
::能源是工作的能力。 所有生物和每个生物细胞都需要能源来执行生命过程,例如分裂和制造分子,以及将许多分子运过细胞膜。 -
The form of energy that living things need for these processes is chemical energy, and it comes from food. Food consists of organic molecules that store energy in their chemical bonds.
::这些过程需要的能量形式是化学能源,它来自食物。 食物由有机分子组成,它们将能量储存在化学链条中。 -
Autotrophs make their own food.
P
lants, for example, make food by photosynthesis. Autotrophs are also called producers.
::例如,植物用光合作用做食物,自发养殖也称为生产者。 -
Heterotrophs obtain food by eating other organisms. Heterotrophs are also
known as
consumers.
::食用其他生物来获取食物的血红营养素也被称为消费者。 -
Organisms mainly use the molecules glucose and ATP for energy. Glucose is a compact, stable form of energy that is carried in the blood and taken up by cells. ATP contains less energy and is used to power cell processes.
::有机体主要使用分子甘蔗糖和ATP作为能量,甘蔗糖是一种紧凑稳定的能量形式,由血液携带,由细胞吸收。ATP含有较少的能量,用于电动细胞过程。 -
The flow of energy through living things begins with photosynthesis, which creates glucose. In a process called cellular respiration,
organisms' cells
break down glucose and make the ATP they need.
::通过活物的能量流动始于光合作用,它会产生葡萄糖。 在所谓的细胞呼吸过程中,生物细胞的细胞会分解葡萄糖,并使得他们需要ATP。
Review
::回顾1. Define energy.
::1. 界定能源。2. Why do living things need energy?
::2. 为什么生活需要能源?3. Compare and contrast the two basic ways that organisms get energy.
::3. 比较和对比生物获得能量的两种基本方式。4. Describe the roles and relationships of the energy molecules glucose and ATP.
::4. 描述能量分子甘蔗糖和ATP的作用和关系。5. Summarize how energy flows through living things.
::5. 总结能源如何通过生物物质流动。6. Explain why the energy used by the human body ultimately comes from the sun.
::6. 解释为什么人体使用的能量最终来自太阳。7. True or False: Some humans (such as vegetarians) are autotrophs.
::7. 真实或假:有些人类(如素食者)是自发的。8. True or False: Glucose stores chemical energy in its bonds.
::8. 真实或假:甘蔗在其债券中储存化学能源。9. Producers are also called ______________ .
::9. 生产者也称为______________________________________________________________________________________________________________________________________________________________________10. Consumers are also called ______________ .
::10. 消费者也被称为 。11. Which of the following stores chemical energy?
::11. 下列哪些储存化学能源?a. ATP
::a. ATPb. glucose
::b. 葡萄糖c. none of the above
::c. 以上无一情况d. both A and B
::d. A 和 B 两者12. Which of the following are not heterotrophs?
::12. 以下哪些不是血化营养症?a. mushrooms (fungi)
::a. 蘑菇(fungi)b. cows
::b. 奶牛c. corn
::c. 玉米d. both A and C
::d. A 和 C 两者13. The cellular process in which glucose is broken down and ATP is made is called _________ ________ .
::13. 葡萄糖分解和ATP制成的细胞过程称为。14. Why does the transformation of ATP to ADP release energy?
::14. 为什么将ATP转换为ADP释放能源?Explore More
::探索更多This video discusses photosynthesis, and how autotrophs and heterotrophs get energy .
::这段影片讨论光合作用, 以及自养和血化如何获得能量。This video outlines the food chain, as well as energy transfer through the trophic levels.
::该视频概述了食物链以及通过营养水平的能源转移。 -
Energy is the ability to do work.
It
is needed by all living things and every living cell to carry out life processes, such as breaking down and building up molecules, and transporting many molecules across cell membranes.
