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  • 生化化合物

    Model of glucose, a key biochemical compound vital for energy in living organisms.

    The opening image is a model of an important chemical . Without it, living things would not have the they need to survive. Compared with most other compounds in living things, molecules of this compound are small and simple. In the model, the black circles represent carbon atoms, the red circles represent oxygen atoms, and the grey circles represent hydrogen atoms.
    ::开张图像是一个重要的化学模型。 没有它, 生物就不会有生存所需的物质。 与生物中大多数其他化合物相比, 这种化合物的分子是小而简单的。 在模型中, 黑圈代表碳原子, 红圈代表氧原子, 灰圈代表氢原子。

    Q: What is the for this compound, and what is its name?
    ::问:这个化合物的用途是什么? 它叫什么名字?

    A: The chemical formula is C 6 H 12 O 6 , and the name of the compound is glucose. In this article you’ll learn more about glucose and other compounds that are essential to life.
    ::A:化学公式是C6H12O6,化合物的名称是葡萄糖。在本篇文章中,你会更多地了解对于生命至关重要的葡萄糖和其他化合物。

    Introduction to Biochemical Compounds
    ::生化化合物介绍

    Glucose is an example of a biochemical compound. The prefix bio- comes from the Greek word that means “life.” A biochemical compound is any carbon-based compound that is found in living things. Biochemical compounds make up the cells and tissues of living things. They are also involved in all life processes, including making and using food for energy. Given their diversity of functions, it’s not surprising that there are millions of different biochemical compounds.
    ::甘蔗是生化化合物的一个例子。 生物前缀来自希腊语中的“生命 ” 。 生化化合物是活物中发现的任何碳基化合物。 生化化合物组成了活物的细胞和组织。 生物化学化合物也涉及所有生命过程,包括制造和使用食物作为能源。 由于其功能的多样性,有数百万种不同的生化化合物并不奇怪。

    Q: Plants make food in the process of . What biochemical compound is synthesized in photosynthesis?
    ::问题:植物在...过程中制造食物。在光合作用中合成了哪些生化化合物?

    A: Glucose is synthesized in photosynthesis.
    ::A:葡萄糖在光合作用中合成。

    Virtually all living things use glucose for energy, but glucose is just one of many examples of biochemical compounds that are found in most or all living things. In fact the similarity in biochemical compounds between living things provides some of the best evidence for the evolution of species from common ancestors. A classic example is the biochemical compound called cytochrome c. It is found in all living organisms because it performs essential life functions. Only slight variations in the molecule exist between closely related species, as you can see in the Figure . The molecule is identical in humans and their closest relatives, the chimpanzees. And even between humans and the single-celled tetrahymena (pictured in the Figure ), the cytochrome c molecule is nearly 50 percent the same.
    ::几乎所有生物都使用甘蔗糖作为能量,但葡萄糖只是大多数或所有生物中发现的许多生化化合物的众多例子之一。事实上,生物物质之间生物化学化合物的相似性为共同祖先物种的进化提供了一些最佳证据。一个典型的例子就是被称为细胞色素的生化化合物。在所有生物中都发现了这种化合物,因为它具有基本的生命功能。正如图中所示,在密切关联的物种之间,分子中只有微小的变化。分子在人类及其近亲即黑猩猩中是相同的。甚至人类和单细胞四血球(图中图示的图示)之间,细胞色素分子也几乎有50%相同。

    Comparison of cytochrome c protein similarities among various species, with Tetrahymena shown.

    Structure of Biochemical Molecules
    ::生化分子结构

    All biochemical molecules contain hydrogen and oxygen as well as carbon. They may also contain nitrogen, phosphorus, and/or sulfur. Almost all biochemical compounds are polymers . Polymers are large molecules that consist of many smaller, repeating molecules, called monomers . Glucose is a monomer of biochemical compounds called starches. In starches and all other biochemical polymers, monomers are joined together by , in which atoms share pairs of .
    ::所有生化分子都含有氢和氧以及碳,还可能含有氮、磷和/或硫,几乎所有生化化合物都是聚合物,聚合物是大型分子,由许多较小的重复分子组成,称为单体分子。甘蔗是被称为恒星的生化化合物的单体。在恒星和所有其他生化聚合物中,单体结合在一起,原子在其中分享一对。

     

    Size of Biochemical Molecules
    ::生化分子的大小

    Most biochemical molecules are macromolecules. The prefix macro- means “large,” and many biochemical molecules are very large indeed. They may contain thousands of monomer molecules. The largest known biochemical molecule is called titin. It plays an important role in muscle contraction. The human form of the molecule contains more than 34,000 monomers. Its chemical formula is C 169723 H 270464 N 45688 O 52243 S 912 . Its chemical name contains almost 190,000 letters, and it has been called the longest word in any language. 
    ::大多数生化分子是大型分子。前缀宏意味着“大 ” , 许多生化分子确实非常大。 它们可能包含数千个单体分子。 已知的最大生化分子叫“ 泰坦 ” 。 它在肌肉收缩中起着重要作用。 分子的人体形式含有34 000多个单体。 它的化学公式是C169723H2704664N45688O52243S912。 它的化学名称包含近190 000个字母, 并且被任何语言称为最长的单词 。

    Classes of Biochemical Compounds
    ::生化化合物类别

    Although there are millions of biochemical compounds, all of them can be grouped into just four main classes: , , , and . The classes are summarized in the Table .
    ::虽然有数百万种生化化合物,但所有这些化合物都可归为四个主要类别:.、.、.和.。

    Class Elements Examples Functions
    Carbohydrates

    carbon
    ::碳碳

    hydrogen
    ::氢氢

    oxygen
    ::氧氧气

    sugars
    ::糖糖

    starches
    ::恒星

    cellulose
    ::纤维纤维素

    provide energy to cells
    ::为单元格提供能量

    store energy in plants
    ::工厂储存能源

    makes up the cell walls of plants
    ::造化植物的细胞壁,

    Proteins

    carbon
    ::碳碳

    hydrogen
    ::氢氢

    oxygen
    ::氧氧气

    nitrogen
    ::氮氮

    sulfur
    ::硫磺

    hormones
    ::荷激素

    up
    ::上上

    regulate life processes
    ::规范生命过程

    Lipids

    carbon
    ::碳碳

    hydrogen
    ::氢氢

    oxygen
    ::氧氧气

    fats
    ::脂肪

    oils
    ::油油油

    store energy in animals
    ::动物储存能源

    store energy in plants
    ::工厂储存能源

    Nucleic acids

    carbon
    ::碳碳

    hydrogen
    ::氢氢

    oxygen
    ::氧氧气

    nitrogen
    ::氮氮

    phosphorus
    ::磷

    DNA
    ::DNA DNA

    RNA
    ::RNA 核纳

    stores genetic information in cells
    ::存储单元格中的遗传信息

    helps cells make proteins
    ::帮助细胞制造蛋白质

    Q: In which class of biochemical compounds would you place glucose?
    ::问题:在哪一类生化化合物中,你会放置葡萄糖?

    A: Glucose is a sugar in the class carbohydrates. Like other carbohydrates, it contains only carbon, hydrogen, and oxygen. It provides energy to the cells of living things.
    ::甲:甘蔗是类碳水化合物中的糖。与其他碳水化合物一样,它只含有碳、氢和氧。它为生物细胞提供能量。

    Q: Look back at the chemical formula for titin. In which class of biochemical compounds should it be placed?
    ::问题:回顾泰廷的化学公式。应该将其放在哪一类生化化合物中?

    A: Titin is a protein. You can tell because it contains sulfur, and proteins are the only biochemical compounds that contain this .
    ::甲:提丁是蛋白质。你可以分辨,因为它含有硫磺,蛋白质是唯一含有这种物质的生化化合物。

    Summary
    ::摘要

    • Biochemical compounds are carbon-based compounds that are found in living things. The similarity in biochemical compounds between living things provides evidence for the evolution of species from common ancestors.
      ::生物化学化合物是活物中发现的碳基化合物,生物物质之间生物化学化合物的相似性为共同祖先物种的进化提供了证据。
    • All biochemical molecules contain hydrogen and oxygen as well as carbon. They may also contain nitrogen, phosphorus, and/or sulfur. Almost all biochemical compounds are polymers.
      ::所有生化分子都含有氢和氧以及碳,还可能含有氮、磷和/或硫,几乎所有生化化合物都是聚合物。
    • Most biochemical molecules are macromolecules, meaning that they are very large. Some contain thousands of monomer molecules.
      ::大多数生化分子是大型分子,意味着它们非常大。有些含有数千个单体分子。
    • Although there are millions of biochemical compounds, all of them can be grouped into just four classes: carbohydrates, proteins, lipids, and nucleic acids.
      ::虽然有数百万种生化化合物,但所有这些化合物都可分为四类:碳水化合物、蛋白质、脂类和核酸。

    Review
    ::回顾

    1. What is a biochemical compound?
      ::什么是生化化合物?
    2. Give a general description of a biochemical molecule.
      ::对生化分子作一般性描述。
    3. List the four classes of biochemical compounds.
      ::列出四类生化化合物。
    4. Which classes of biochemical compounds store energy in living things?
      ::哪几类生化化合物在生物物质中储存能量?
    5. Which classes of biochemical compounds contain oxygen?
      ::哪几类生化化合物含有氧?