Section outline

  • General

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  • 液溶解

    What you will learn
    ::你会学到什么

    • Steps of the glycolysis pathway
      ::凝解路径步骤
    • Energy-carrying molecules formed during glycolysis
      ::溶解过程中形成的含有能量的分子

    Two hands slicing a glucose molecule in half, illustrating the glycolysis process.

    How do you slice a molecule of glucose in half?
    ::你怎么把葡萄糖的分子切成两半?

    With sharp knives? Not really. But you essentially slice it in half through glycolysis. This is an extremely important part of . It happens all the time, both with and without oxygen. And in the process, transfers some energy to ATP .
    ::用锋利的刀子吗?不是。 但你基本上通过水解将其切成两半。 这是最重要的部分。 它经常发生, 无论有没有氧气。 在这个过程中, 将一些能量转移给ATP。

    Cellular Respiration Stage I: Glycolysis
    ::细胞呼吸第一阶段:液解

    The first stage of cellular respiration is glycolysis . It does not require oxygen, and it does not take place in the - it takes place in the cytosol of the cytoplasm .
    ::细胞呼吸的第一阶段是透析,不需要氧气,也不发生在细胞顶层的细胞索中。

    When was the last time you enjoyed yogurt on your breakfast cereal, or had a tetanus shot? These experiences may appear unconnected, but both relate to which do not use oxygen to make ATP. In fact, tetanus bacteria cannot survive if oxygen is present. However, Lactobacillus acidophilus (bacteria which make yogurt) and Clostridium tetani (bacteria which cause tetanus or lockjaw) share with nearly all organisms the first stage of cellular respiration, glycolysis. Because glycolysis is universal, whereas aerobic (oxygen-requiring) cellular respiration is not, most biologists consider it to be the most fundamental and primitive pathway for making ATP.
    ::上一次你在早餐麦片上享受酸奶是什么时候,还是曾经注射过破伤风?这些经验可能看起来没有联系,但都与不使用氧气制造ATP有关。事实上,如果氧气存在,破伤风细菌就无法存活下来。然而,Lactobcillus酸性philus(制造酸奶的细菌)和Clostridium Titani(导致破伤风或锁扎的细菌)与几乎所有生物分享了细胞呼吸的第一阶段,即液解。因为水解是普遍性的,而氧(氧气)细胞呼吸不是,大多数生物学家认为这是进行ATP的最根本和最原始的途径。

    Splitting Glucose
    ::分割葡萄糖

    The word glycolysis means “ glucose splitting,” which is exactly what happens in this stage. split a molecule of glucose into two molecules of pyruvate (also known as pyruvic acid). This occurs in several steps, as shown in the Figure . 
    ::溶解一词的意思是“甘蔗分解 ” , 这正是目前阶段发生的情况。 将葡萄糖分子分裂成两种硫酸分子(也称为pyruvic酸 ) 。 这在几个步骤中发生,如图所示。

    Glycolysis process, glucose splitting into two pyruvate molecules, producing ATP.
    In glycolysis, glucose (C6) is split into two 3-carbon (C3) pyruvate molecules. This releases energy, which is transferred to ATP. How many ATP molecules are made during this stage of cellular respiration?

     

     

    Results of Glycolysis
    ::液分解结果

    Energy is needed at the start of glycolysis to split the glucose molecule into two pyruvate molecules. These two molecules go on to stage II of cellular respiration. The energy to split glucose is provided by two molecules of ATP. As glycolysis proceeds, energy is released, and the energy is used to make four molecules of ATP. As a result, there is a net gain of two ATP molecules during glycolysis. During this stage, high-energy electrons are also transferred to molecules of NAD + to produce two molecules of NADH , another energy-carrying molecule. NADH is used in stage III of cellular respiration to make more ATP.
    ::溶解开始时需要能量,以便将葡萄糖分子分成两个回旋分子。这两个分子继续进入细胞呼吸的第二阶段。分裂葡萄糖的能量由ATP的两个分子提供。随着溶解的收益,能量释放出来,能量被用来制造ATP的四个分子。因此,在解析过程中,有两个ATP分子的净收益。在这一阶段,高能电子还被转移到NAD+的分子中,产生两个NADH的分子,另一个能量携带分子。NADH在细胞呼吸的第三阶段中被用来制造更多的ATP。

    DID YOU KNOW?
    The most common pathway of glycolysis was described by Gustav Embden, Otto Meyerhof, and Jakub Karol Parnas. Glycolysis is therefore known as the Embden–Meyerhof–Parnas (EMP) pathway.
     

    Summary
    ::摘要

    • The first stage of cellular respiration is glycolysis. It does not require oxygen.
      ::细胞呼吸的第一阶段是透析,不需要氧气。
    • During glycolysis, one glucose molecule is split into two pyruvate molecules, using 2 ATP while producing 4 ATP and 2 NADH molecules.
      ::在液解过程中,一个葡萄糖分子分解成两个微粒分子,使用2个ATP,生产4个ATP和2个NADH分子。

    Review
    ::回顾

    1. What is glycolysis?
      ::什么是液解?
    2. Describe what happens during glycolysis. How many ATP and NADH molecules are gained during this stage?
      ::描述在水解过程中发生的情况:在这一阶段有多少ATP分子和NADH分子?
    3. Defend this statement: ‘‘Glycolysis is a universal and ancient pathway for making ATP’’.
      ::抗争声明: 液解是一种普遍和古老的制定ATP的路径。