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  • 低温酸化发酵 -- -- 高级

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    Is there enough ATP?
    ::有足够的ATP吗?

    Yes. But not to keep this effort up for a long time. Short spurts of sprinting are sustained by in muscle . This produces just enough ATP to allow these short bursts of increased activity.
    ::短短的短短冲刺由肌肉支撑。这只产生足够的ATP, 足以让这些短短的波纹增加活动。

    Lactic Acid Fermentation: Muscle Cells and Yogurt
    ::电法酸发酵:肌肉细胞和酸奶

    For chicken or turkey dinners, do you prefer light meat or dark? Do you consider yourself a sprinter or a long-distance runner? What is the biological difference between light meat or dark meat? Or between the two types of runners? Would you believe it has something to do with muscle color?
    ::对于鸡肉或火鸡晚餐,你更喜欢浅肉还是暗肉?你认为自己是短跑或长途跑步者吗?浅肉或暗肉之间的生物区别是什么?还是这两种选手之间的生物区别是什么?你相信这与肌肉颜色有关吗?

     

    • Light meat
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    • Red meat
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    • Sprinting
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    • Endurance - Marathon
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    Light meat or dark? Sprinting or endurance? Muscle cells know two ways of making ATP – aerobic and anaerobic respiration.

    Are Drumsticks and Athletic Prowess Related?
    ::鼓棒和运动功率与鼓棒有关吗?

    Muscle color reflects its specialization for aerobic or anaerobic metabolism . Although humans are obligate aerobes , our muscle cells have not given up on ancient pathways that allow them to keep producing ATP quickly when oxygen runs low. The difference is more pronounced in chickens and grouse ( Figure  ), which stand around all day on their legs. For long periods of time, they carry out aerobic respiration in their “specialized-for-endurance” red . If you are familiar with grouse, you know that these “flush” with great speed over short distances. Such “sprinting” flight depends on in the white cells of breast and wing muscle, allowing rapid production of ATP in low-oxygen situations.
    ::肌肉颜色反映了它专门从事有氧或厌氧新陈代谢的专长。虽然人类有义务接受厌食,但我们的肌肉细胞并没有放弃在氧气过低时允许它们快速生产ATP的古老途径。在鸡和卷毛(Figure ) 方面差异更为明显,这些鸡和卷毛(Figure ) 整天站在腿上。在很长的一段时间里,它们在其“专用耐药性”红中进行有氧呼吸。如果你熟悉粗糙,你就会知道这些“鲜花 ” , 速度很快。 这种“打印”飞行取决于乳房和翅膀肌肉的白细胞,允许在低氧情况下快速生产ATP。

    No human muscle is all red or all white, but chances are, if you excel at sprinting short distances or at a sport such as weight lifting, you have more white glycolytic fibers in your leg muscles, allowing anaerobic respiration. If you run marathons, you probably have more red oxidative fibers, performing aerobic respiration.
    ::没有人类肌肉是红色或白色的,但机会是,如果你在短距离跑步或举重等运动上表现出色,你的腿肌肉中就会有更多的白甘油纤维,允许厌氧呼吸。如果你跑马拉松,你可能会有更多的红氧化纤维,进行有氧呼吸。

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    Ruffed grouse use anaerobic respiration (lactic acid fermentation) in wing and breast muscles for quick bursts of speed to escape from predators.

    Lactic Acid Fermentation
    ::电法酸发酵

    You may have not been aware that your muscle cells can ferment. Fermentation is the process of producing ATP in the absence of oxygen, through alone. Recall that glycolysis breaks a glucose molecule into two pyruvate molecules, producing a net gain of two ATP and two NADH molecules. Lactic acid fermentation is the type of anaerobic respiration carried out by yogurt ( Lactobacillus and others) and by your own muscle cells when you work them hard and fast.
    ::您可能不知道您的肌肉细胞会发酵。 发酵是在没有氧的情况下单独通过氧气生产ATP的过程。 提醒注意, 液解将葡萄糖分子分解成两个闪烁分子, 产生两个ATP分子和两个NADH分子的净收益。 酸发酵是酸酸( 乳酸) 和自身肌肉细胞在努力和快速工作时进行的厌氧呼吸类型。

    Lactic acid fermentation converts the 3-carbon pyruvate to the 3-carbon lactic acid (C 3 H 6 O 3 ) (see the Figure  ) and regenerates NAD + in the process, allowing glycolysis to continue to make ATP in low-oxygen conditions. Since there is a limited supply of NAD + available in any given cell, this electron acceptor must be regenerated to allow ATP production to continue. To achieve this, NADH donates its extra electrons to the pyruvate molecules, regenerating NAD + . Lactic acid is formed by the reduction of pyruvate.
    ::远距离酸发酵法将3-碳蒸发器转换为3-碳液酸(C3H6O3)(见图),并在此过程中再生NAD+,允许在低氧条件下继续进行水解,使ATP在低氧条件下继续成为ATP。由于任何特定电池中NAD+的供应有限,该电子接收器必须再生,以便能够继续生产ATP。为此,NADH将其额外电子捐赠给蒸发分子,再生NAD+。

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    Lactic acid, C3H6O3.

    Lactic acid fermentation converts pyruvate to lactic acid, and regenerates NAD + from NADH:
    ::抗酸发酵法将回旋剂转化成抗酸,并从NADH再生NAD+:

    C 3 H 3 O 3 (pyruvate) + NADH → C 3 H 6 O 3 (lactic acid) + NAD +
    ::C3H3O3(丙硝酸)+NADH + NADH + C3H6O3(杀菌酸)+ NAD+

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    Lactic acid fermentation makes ATP in the absence of oxygen by converting glucose to lactic acid (through a pyruvate intermediate). Making lactic acid from pyruvate oxidizes NADH, regenerating NAD+ so that glycolysis can continue to make more ATP rapidly. Each circle represents a carbon atom.

    For Lactobacillus bacteria, the acid resulting from fermentation kills bacterial competitors in buttermilk, yogurt, and some cottage cheese. The benefits extend to humans who enjoy these foods, as well ( Figure  ).
    ::对于乳腺杆菌细菌来说,发酵产生的酸会杀死奶油、酸奶和一些干酪中的细菌竞争者。 享受这些食物的人类也从中获益(图 ) 。

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    Lactobacillus bacteria use the same type of anaerobic respiration as our muscle cells. Lactic acid reduces competition from other bacteria and flavors yogurt.

    You may have noticed this type of fermentation in your own muscles because muscle fatigue and pain are associated with lactic acid. Lactic acid accumulates in your muscle cells as fermentation proceeds during times of strenuous . During these times, your respiratory and cardiovascular systems cannot transport oxygen to your muscle cells, especially those in your legs, fast enough to maintain aerobic respiration. To allow the continuous production of some ATP, your muscle cells use lactic acid fermentation.
    ::肌肉疲劳和疼痛与乳酸相关,因此你可能已经注意到自己肌肉中的这种发酵方式。在紧张时期,脑酸会随着发酵而累积在肌肉细胞中。在这段时期,你的呼吸和心血管系统无法将氧气输送到肌肉细胞中,特别是腿部的肌肉细胞中,速度足以保持有氧呼吸。为了连续生产一些ATP,你的肌肉细胞会使用乳酸发酵。

    Summary
    ::摘要

    • Some bacteria, including those we employ to make yogurt, make ATP using lactic acid fermentation.
      ::一些细菌,包括我们用来做酸奶的细菌 使用抗酸发酵法做ATP
    • Muscle cells can continue to produce ATP when oxygen runs low using lactic acid fermentation, but muscle fatigue and pain may result.
      ::肌肉细胞可以继续产生ATP,当氧气使用乳酸发酵过低时,但肌肉疲劳和疼痛可能会发生。

    Review
    ::回顾

    1. Define lactic acid fermentation.
      ::定义白酸发酵。
    2. Identify yourself as a “sprinter” or an “endurance runner” and predict the type of muscle fiber (red or white) that predominates in your body. Explain your reasoning.
      ::指出自己是“指纹”或“耐久跑者”,并预测身体中占主导地位的肌肉纤维(红或白)类型。
    3. What is the chemical equation of lactic acid fermentation?
      ::乳酸发酵的化学方程式是什么?