A tree converts disorder to order with a little help from the Sun

一棵树在太阳的协助下将无序转化为有序

The concept of entropy and the second law of thermodynamics suggests that systems naturally progress from order to disorder. If so, how do biological systems develop and maintain such a high degree of order? Is this a violation of the second law of thermodynamics?

熵的概念和热力学第二定律表明，系统倾向于从有序走向无序。如果真是这样，生物系统是如何发展并维持如此高的有序性呢？这是否违反了热力学第二定律？

Order can be produced with an expenditure of energy, and the order associated with life on the earth is produced with the aid of energy from the sun. The raw materials for the nutrients for life on the Earth are just carbon dioxide and water! The mechanisms of advanced plant and animal life add nitrogen, phosphorus and sulfur with most of life's operational mechanisms accomplished with the elements summarized in the mnemonic CHONPS.

秩序可以通过消耗能量来产生，而与地球上的生命相关的秩序则是借助太阳提供的能量产生的。地球上的生命所需的原始材料仅仅是二氧化碳和水！高级植物和动物的生命机制会添加氮、磷和硫，而生命大部分运作机制都是利用总结在mnemonic CHONPS中的元素完成的。

The building materials are in a highly disordered state - gases, liquids and vapors. The tree takes in carbon dioxide from the air, water from the earth as well as a small amount from water vapor in the air. From this disordered beginning, it produces the highly ordered and highly constrained sugar molecules, like glucose. The radiant energy from the Sun gets transferred to the bond energies of the carbons and the other atoms in the glucose molecule. In addition to making the sugars, the plants also release oxygen which is essential for animal life.

建筑材料处于高度无序的状态——气体、液体和蒸汽。树木从空气中吸收二氧化碳，从地球中吸收水分，同时也能吸收空气中少量的水蒸气。从这种无序的起点开始，它产生高度有序且高度约束的糖分子，如葡萄糖。太阳的辐射能转移到葡萄糖分子中碳原子和其他原子的键能中。除了产生糖分外，植物还会释放氧气，这对动物生命至关重要。

The leaves use the energy from the sun in tiny energy factories called chloroplasts. Using chlorophyll in the process called photosynthesis, they convert the sun's energy into storable form in ordered sugar molecules.

树叶利用阳光的能量，在称为叶绿体的微小能量工厂中进行转换。通过光合作用过程中的叶绿素，它们将阳光的能量转化为可储存的形式，储存在有序的糖分子中。

As an example of the scope of this process, consider a mature maple tree. It may have 500 pounds of green leaves employed in the process of photosynthesis. Having a leaf surface area of several hundred square meters, it is capable of making some 2 tons of sugar.

作为一个例子，说明这一过程的范围，考虑一棵成熟的枫树。它可能有500磅的绿叶用于光合作用。其叶面积可达数百平方米，能够产生约2吨的糖。

The process of photosynthesis in plants stores energy in the plants which can be used for accomplishing work. Some of the energy is used for the synthesis of carbohydrates. These carbohydrates may be simple sugars like glucose or complex combinations of sugars. Some of the common carbohydrates are:

植物的光合作用过程将能量储存于植物中，这些能量可用于完成工作。其中一部分能量用于合成碳水化合物。这些碳水化合物可能是简单的糖如葡萄糖，或是复杂的糖类组合。一些常见的碳水化合物包括：

Cellulose 纤维素	Long chains of glucose molecules which are fairly linear. They help maintain the plant structure - the wood of trees is primarily cellulose. 由较为线性的葡萄糖分子长链组成。它们有助于维持植物结构——树木的木材主要由纤维素构成。
Starch 淀粉	More highly branched chains of glucose molecules. They are produced by plants and serve as energy resources for the plants. They can be metabolized by humans and other animals for energy. 更分支的葡萄糖分子链。它们由植物产生，并作为植物的能量来源。它们可以被人类和其他动物代谢以获取能量。
Glycogen 糖原	Even more highly branched chains of glucose, but similar to starches. Used by plants and animals for energy storage. For animals, this glycogen storage is primarily in the muscles. 更加分支的葡萄糖链，但类似于淀粉。被植物和动物用于能量存储。对于动物来说，这种糖原存储主要存在于肌肉中。

In animal systems there are also small structures within the cells called mitochondria which use the energy stored in sugar molecules from food to form more highly ordered structures.

在动物细胞中，也有被称为线粒体的微小结构，它们利用食物中糖分子储存的能量，形成更加有序的结构。

Order and disorder in biological systems.

生物系统中的有序与无序。

Index

Second law concepts

索引第二定律概念

HyperPhysics***** Biology

HyperPhysics ***** 生物学

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