Section outline

  • General

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  • 核酸

    What you will learn
    ::你会学到什么

    • Nucleic acids and their structure
      ::核心酸及其结构
    • Role of nucleic acids
      ::核酸的作用

    Binary code pattern representing genetic information in nucleic acids.

    You may have heard that something is "encoded in your DNA." What does that mean?
    ::你可能听说了某种"在你的DNA中编码" 是什么意思?

    Nucleic acids. Essentially the "instructions" or the "code" of life. Deoxyribonucleic acid, or , carries the unique code to make the that give you your traits. Half of this code comes from your biological mother and a half from your biological father. Therefore, every person that has ever lived - except for identical twins - has his or her own unique sequence of code - or instructions - or DNA.
    ::核糖核酸。 基本上, 生命的“ 指令” 或“ 代码 ” 。 脱氧核糖核酸, 或者, 带有独特的代码来制造给你的特性。 一半的代码来自你的生母, 一半来自你的生父。 因此, 除了同父异母的双胞胎之外, 每一个曾经生活过的人, 都有自己独特的代码序列, 或者指令或者DNA 。

    Nucleic Acids
    ::核酸

    A nucleic acid is an , such as DNA or , that is built of monomers called nucleotides . Many nucleotides bind together to form a chain called a polynucleotide . The nucleic acid DNA (deoxyribonucleic acid) consists of two polynucleotide chains. The nucleic acid RNA (ribonucleic acid) consists of just one polynucleotide chain. Adenosine Triphosphate (ATP) is another important nucleic acid. ATP is described as the " energy currency" of the or the "molecular unit of currency." One molecule of ATP contains three phosphate groups.
    ::核酸是一种由单细胞制造的,如DNA或核糖核酸。许多核糖核酸结合成一个称为聚核酸的链条。核酸DNA(脱氧核糖核酸)由两个多核酸链组成。核酸RNA(核糖核酸)仅由一个聚核酸链组成。亚丁辛三磷酸(ATP)是另一个重要的核酸。ATP被称为“能量货币”或“货币分子单位”。ATP的一个分子包含三个磷酸组。

    Structure of Nucleic Acids
    ::核酸结构

    Each nucleotide consists of three smaller molecules as shown in the Figure :
    ::如图所示,每个核分裂分子由三个较小的分子组成:

    1. sugar
      ::糖糖糖糖
    2. phosphate group
      ::磷酸酯类
    3. nitrogen base
      ::氮基基氮基

    If you look at the Figure , you will see that the sugar of one nucleotide binds to the phosphate group of the next nucleotide. These two molecules alternate to form the backbone of the nucleotide chain. This backbone is known as the sugar-phosphate backbone.
    ::如果你看看图, 你会看到一个核酸的糖与下一个核酸的磷酸组结合。 这两个分子可以互换成核酸链的脊柱。 这个脊柱被称为甘酸磷基。

     

    Chemical structure of a nucleotide showing phosphate, sugar, and nitrogenous base.
    Structure of a nucleotide

    The nitrogen bases in a nucleic acid stick out from the backbone. There are four different types of bases: cytosine (C), adenine (A), guanine (G), and either thymine (T) in DNA, or uracil (U) in RNA. In DNA, bonds form between bases on the two nucleotide chains and hold the chains together. Each type of base binds with just one other type of base: cytosine always binds with guanine, and adenine always binds with thymine. These pairs of bases are called complementary base pairs .
    ::核酸中的氮基从骨干中伸出来。 有四种不同的基础: 细胞素(C), 腺素(A), 腺素(G), 以及DNA中的胸腺(T), 或RNA中的尿素(U)。 在DNA中, 核酸链中的两个基点之间形成债券, 并将链子固定在一起。 每一种基点都与另外一种基点捆绑在一起: 细胞素总是与guanine捆绑在一起, 腺素总是与胸膜捆绑在一起。 这些基点的配对被称为互补基底对。

    CAn you Build?

    Try to bond the nitrogen bases on the right, with the complementary base. Start by dragging the nitrogen bases on the right.
    ::尝试将右边的氮基与补充基连接起来。 开始将右边的氮基拖到右边 。

     

     

    DID YOU KNOW?
    Although there are about 8.7 million known of living organisms on Earth, their genetic information is only made of four letters A, T, G, and C.
     

    The binding of complementary bases allows DNA molecules to take their well-known shape, called a double helix , which is shown in the Figure . A double helix is like a twisted ladder. The double helix shape forms naturally and is very strong, making the two polynucleotide chains difficult to break apart.
    ::互补基点的结合使DNA分子能够呈现出其众所周知的形状,称为双螺旋,如图所示。双螺旋就像一个扭曲的梯子。双螺旋形状自然形成并且非常坚固,使两个多核酸链条难以分解。

    The structure of a DNA double helix and its coiling into chromosomes.
    DNA Molecule. Bonds between complementary bases help form the double helix of a DNA molecule. The letters A, T, G, and C stand for the bases adenine, thymine, guanine, and cytosine. The sequence of these four bases in DNA is a code that carries instructions for making proteins. Shown is how the DNA winds into a chromosome.
    DID YOU KNOW?
    Due to one less oxygen in its sugar component, DNA is a more stable molecule than RNA. This property is useful in keeping the genetic information safe.
     

    Roles of Nucleic Acids
    ::核酸的作用

    DNA is also known as the hereditary material or genetic information. It is found in genes , and its sequence of bases makes up a code. Between 'starts' and 'stops', the code carries instructions for the correct sequence of amino acids in a protein. DNA and RNA have different functions relating to the and proteins. Like a computer code, DNA contains the genetic instructions for the correct sequence of amino acids in proteins. RNA uses the information in DNA to assemble the correct amino acids and help make the protein. The information in DNA is passed from parent cells to daughter cells whenever cells divide. The information in DNA is also passed from parents to offspring when organisms reproduce. This is how inherited characteristics are passed from one generation to the next.
    ::DNA也被称为遗传物质或遗传信息。 它在基因中被发现, 并且它的序列构成一个代码。 在“ 起始” 和“ 停止 ” 之间, 代码含有蛋白质中氨基酸正确序列的指示。 DNA和 RNA 具有与蛋白质和蛋白质相关的不同功能。 像计算机代码一样, DNA包含蛋白质中氨基酸正确序列的遗传指令。 RNA 使用DNA 中的信息来组装正确的氨基酸, 并帮助生成蛋白质。 DNA中的信息在细胞分裂时从母细胞传递给后代细胞。 DNA中的信息也由父母传递给生物繁殖时的后代。 这就是遗传特征如何从一代传到下一代。

     

     

     

     

    Summary
    ::摘要

    • DNA, RNA, and ATP are nucleic acids. Polynucleotides like DNA and RNA are built of monomers called nucleotides.
      ::DNA、RNA和ATP是核糖核酸。 像DNA和RNA这样的多核核酸由叫做核酸的单体组成。
    • The bases of DNA are adenine, guanine, cytosine, and thymine. In RNA, thymine is replaced by uracil.
      ::DNA的基底是、、细胞素和甲状腺。 在RNA, 甲状腺被聚氨酯取代。
    • In DNA, A always binds to T, and G always binds to C.
      ::在DNA中,A总是与T有联系,G总是与C有联系。
    • The shape of the DNA molecule is known as a double helix.
      ::DNA分子的形状被称为双螺旋。
    • DNA contains the genetic instructions for the correct sequence of amino acids in proteins. RNA uses the information in DNA to assemble the correct amino acids and help make the protein.
      ::DNA含有蛋白质中氨基酸正确序列的基因说明。 RNA利用DNA中的信息组装正确的氨基酸并帮助制造蛋白质。

    Review
    ::回顾

    1. Identify the three parts of a nucleotide.
      ::识别核糖核酸的三部分。
    2. What is DNA?
      ::DNA是什么? DNA吗? What is DNA?
    3. What are complementary base pairs? Give an example.
      ::什么是互补的基对?举个例子。
    4. Describe the shape of DNA.
      ::描述DNA的形状
    5. How are DNA and RNA related to proteins?
      ::DNA和RNA与蛋白质有何关联?