章节大纲

  • 常规

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  • 发酵

    A wooden barrel with red and white wine glasses next to green and black grapes.
     

    How is wine made?
    ::酒怎么酿的?

    You probably realize that grapes are needed to make wine. You might not realize, however, that  yeast  are also central in the process of making wine. Yeast take the sugars from the grapes and convert them into alcohol through the process of fermentation.
    ::您可能意识到葡萄是酿酒所需要的。 但是,您可能没有意识到酵母也是酿酒过程中的核心。 酵母从葡萄中取出糖,通过发酵过程将其转化为酒精。

    Fermentation
    ::发酵

    Sometimes  cells  need to obtain  energy  from sugar, but there is no oxygen present to complete  . In this situation, cellular respiration can be  anaerobic , occurring in the absence of oxygen. In this process, called  fermentation , only the first step of  respiration ,  glycolysis , occurs, producing two  ATP ; no additional ATP is produced. Therefore, the  organism  only obtains the two ATP molecules per  glucose   molecule  from glycolysis. Compared to the 36-38 ATP produced under  aerobic  conditions,  anaerobic respiration  is not a very efficient process. Fermentation allows the first step of cellular respiration to continue and produce some ATP, even without oxygen.
    ::有时细胞需要从糖中获取能量,但是没有氧气可以完成。在这种情况下,细胞呼吸可以是厌氧的,在缺氧的情况下发生。在这个过程中,被称为发酵的过程,只是呼吸的第一步,即液解析,产生两个ATP;没有生产额外的ATP。因此,有机体只能从凝解中获得两个ATP分子,每个Glucose分子。与在有氧条件下产生的36-38ATP相比,厌氧呼吸不是一个非常有效的过程。发酵使得细胞呼吸的第一步能够继续并产生一些ATP,即使没有氧。

    Yeast (single-celled eukaryotic organisms) perform  alcoholic fermentation  in the absence of oxygen. The products of alcoholic fermentation are ethyl alcohol (drinking alcohol) and carbon dioxide gas. This process is used to make common food and drinks. For example, alcoholic fermentation is used to bake bread. The carbon dioxide bubbles allow the bread to rise and become fluffy. Meanwhile, the alcohol evaporates. In wine making, the sugars of grapes are fermented to produce wine. The sugars are the starting materials for glycolysis.
    ::以酒精发酵为产物。酒精发酵的产物是乙醇(酒精饮料)和二氧化碳气体。这种工艺用于制造普通食品和饮料。例如,酒精发酵用于烘烤面包。二氧化碳泡沫允许面包上升并变得毛发。与此同时,酒精蒸发。在酿酒过程中,葡萄糖被发酵以生产葡萄酒。糖是进行凝胶分析的起始材料。

    Animals  and some  bacteria  and   carry out  lactic acid fermentation .  Lactic acid is a waste product of this process. Our   perform lactic acid fermentation during strenuous  , since oxygen cannot be delivered to the muscles quickly enough. Bacteria that produce lactic acid are used to make cheese and yogurt. The lactic acid causes the  proteins  in milk to thicken. Lactic acid also causes tooth decay, because bacteria use the sugars in your mouth for energy.
    ::动物和一些细菌,并进行乳酸发酵。 酸酸是这一过程的废物产物。 我们在艰苦时期进行酸酸发酵,因为氧气无法迅速送到肌肉部。 产生酸奶的细菌被用来制造奶酪和酸奶。 酸奶导致牛奶中的蛋白质变厚。 酸酸还会导致牙齿衰竭,因为细菌用你嘴里的糖来制造能量。

    Pictured below are some products of fermentation ( Figure   ).
    ::以下是发酵的一些产品(图)。

    A cheese platter with wine, showcasing products of lactic and alcoholic fermentation.
     
    Products of fermentation include cheese (lactic acid fermentation) and wine (alcoholic fermentation).

    Gut Fermentation
    ::Gut 发酵

    Behind every fart is an army of gut bacteria undergoing some crazy biochemistry. These bacteria break down the remains of digested food through fermentation, creating gas in the process. Learn what these bacteria have in common with beer brewing at  .
    ::每个放屁的背后都是一群直肠细菌 正在经历一些疯狂的生物化学。这些细菌通过发酵分解消化食物的残渣,在过程中产生气体。了解这些细菌与啤酒酿造的相同之处。

     

     

    Summary
    ::摘要

    • Fermentation happens in the absence of oxygen.
      ::没有氧气,发酵就会发生
    • Only the two ATP from glycolysis are produced under anaerobic conditions.
      ::在厌氧条件下,仅生产了两台通过凝解解的ATP。
    • Alcoholic fermentation and lactic acid fermentation are the two types of fermentation.
      ::酒精发酵和乳酸发酵是两种发酵类型。

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    • Anaerobic Respiration  at   (2:01)
      ::抗氧呼吸(2:01)

     

     

    1. Where in the cell does anaerobic respiration take place?
      ::牢房里哪里有厌氧呼吸?
    1. What happens to pyruvate during anaerobic respiration? How does yeast differ from other organisms regarding the fate of pyruvate?
      ::在厌氧呼吸期间,回旋作用会如何?酵母与其他生物在回旋作用的命运方面有何不同?
    1. How can glycolysis participate in anaerobic repiration?
      ::液解如何参与厌氧反应?
    1. How much ATP is produced by the breakdown of pyruvate? How much ATP is produced overall by fermentation? Where does this ATP come from?
      ::发酵总产值是多少?这一ATP来自何处?

    Review
     ::回顾

    1. What is the difference between alcoholic fermentation and lactic acid fermentation?
      ::酒精发酵和乳酸发酵之间有什么区别?
    1. If an organism could make ATP from sugars with or without the presence of oxygen, which would be preferred and why?
      ::如果有机体可以用含氧或不含氧的糖制成ATP,那么更可取的是什么以及为什么?