Lactic acid fermentation and alcoholic fermentation are two types of anaerobic respiration methods. Therefore, both lactic acid and alcoholic fermentation do not require oxygen. The main difference between lactic acid and alcoholic fermentation is that lactic acid fermentation produces lactic acid molecules from pyruvate whereas alcoholic fermentation produces ethyl alcohol and carbon dioxide. Alcoholic fermentation of yeast is used in the food industry to produce wine and beer. Lactic acid fermentation occurs in the muscle cells when they are run out of oxygen. Show
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What is Lactic Acid Fermentation Key Terms: Alcoholic Fermentation, Anaerobic Respiration, Carbon Dioxide, Cytosol, Glucose, Heterolactic Fermentation, Homolactic Fermentation, Lactic Acid Fermentation, Pyruvate What is Lactic Acid FermentationLactic acid fermentation refers to a metabolic process by which glucose is converted into the metabolite: lactate and cellular energy. Generally, lactic acid fermentation is carried out by bacteria such as Lactobacillus and yeast. It occurs in two major steps: glycolysis and fermentation. Both glycolysis and lactic acid fermentation occur in the cytosol. Glycolysis is the first step of both lactic acid and alcoholic fermentation. During glycolysis, hexose sugars are broken down into two pyruvate molecules. Pyruvate is composed of three carbon molecules. Two NADH molecules and four ATP molecules are produced by this process. Since two ATP molecules are consumed by the process itself, the net yield of ATP is two in the fermentation. The process of lactic acid fermentation is shown in figure 1. Figure 1: Lactic Acid Fermentation Two types of lactic acid fermentations can occur in the cytosol. They are homolactic fermentation and heterolactic fermentation. Homolactic FermentationIn homolactic fermentation, two lactic acid molecules are generated by the action of the enzyme lactate dehydrogenase. The chemical reaction for homolactic fermentation is shown below. C6H12O6 → 2 CH3CHOHCOOH Heterolactic FermentationIn heterolactic fermentation, lactic acid, ethanol, and carbon dioxide are produced with the aid of both lactate dehydrogenase and pyruvate decarboxylase enzymes. The chemical reaction of heterolactic fermentation is shown below. C6H12O6 → CH3CHOHCOOH + C2H5OH + CO2 Muscle cells typically undergo aerobic respiration in the presence of oxygen. But when the oxygen supply is poor, they undergo lactic acid fermentation. This may occur due to extreme exercising or severe straining. Muscle cells undergo lactic acid fermentation to fulfill quicker energy requirements. The production of lactic acid in muscles may cause cramps or stiffness in muscles. The structure of a lactic acid molecule is shown in figure 2. Figure 2: Lactic Acid Lactic acid fermentation has a wide range of applications in the food industry. Lactobacillus spps are used in the production of yogurt, cheese, sauerkraut, kefir, and imparting a sour taste to food. What is Alcoholic FermentationAlcoholic fermentation refers to a metabolic process by which glucose is converted into ethanol and carbon dioxide. It is mainly carried out by yeast and some other bacteria. Alcoholic fermentation also occurs in the cytosol in the absence of oxygen. The two pyruvate molecules produced in the glycolysis are converted into ethanol and carbon dioxide. The fate of the pyruvate in the alcoholic fermentation is shown in figure 3. Figure 3: Alcoholic Fermentation The conversion of pyruvate into ethanol and carbon dioxide occurs in two steps. The first reaction is catalyzed by the enzyme pyruvate decarboxylase while the second reaction is catalyzed by the alcohol dehydrogenase. The net ATP production is same in both lactic acid and alcoholic fermentation as the second reaction of both processes do not yield ATP. The two NADH molecules produced by glycolysis are used in the second step in both lactic acid and alcoholic fermentation. Alcoholic fermentation is used the bread baking. The carbon dioxide produced by alcoholic fermentation cause the bread to rise. Alcoholic fermentation is also used in the production of alcoholic beverages such as wine, beer, whiskey, vodka, and rum. Similarities Between Lactic Acid and Alcoholic Fermentation
Difference Between Lactic Acid and Alcoholic FermentationDefinitionLactic Acid Fermentation: Lactic acid fermentation refers to a metabolic process by which glucose is converted into the metabolite: lactate and cellular energy. Alcoholic Fermentation: Alcoholic fermentation refers to a metabolic process by which glucose is converted into ethanol and carbon dioxide. OccurrenceLactic Acid Fermentation:Lactic acid fermentation occurs in Lactobacillus spps, yeast, and muscle cells. Alcoholic Fermentation:Alcoholic fermentation occurs in yeast and other microorganisms. ProductsLactic Acid Fermentation:Lactic acid fermentation produces lactic acid molecules from the pyruvate. Alcoholic Fermentation: Alcoholic fermentation produces ethanol and carbon dioxide from the pyruvate molecule. EnzymesLactic Acid Fermentation: Lactate dehydrogenase and pyruvate decarboxylase are the two enzymes involved in the lactic acid fermentation. Alcoholic Fermentation: Pyruvate decarboxylase and alcohol dehydrogenase are the two enzymes involved in the alcoholic fermentation. In the Food IndustryLactic Acid Fermentation:Lactic acid fermentation is used in the production of yogurt and cheese. Alcoholic Fermentation:Alcoholic fermentation is used in the production of bread, beer, wine, and vinegar. ConclusionLactic acid and alcoholic fermentation are two mechanisms involved in the respiration in the absence of oxygen. Both types of fermentation occur in the cytosol. Glycolysis is the first step of both lactic acid and alcoholic fermentation, which produced pyruvate. Lactic acid fermentation produces lactic acid molecules from pyruvate while alcoholic fermentation produces ethanol and carbon dioxide from pyruvate. The main difference between lactic acid and alcohol fermentation is the products of each fermentation. Reference:1. “Lactic Acid Fermentation.” BiologyWise, Available here. Image Courtesy:1. “Figure 07 05 02” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia What is the function of both alcohol and lactic acid fermentation?When yeast cells are kept in an anaerobic environment (i.e., without oxygen), they switch to alcoholic fermentation to generate usable energy from food. Like lactic acid fermentation, alcoholic fermentation generates NAD+ so that glycolysis can continue to produce ATP.
What is alcoholic fermentation and lactic acid fermentation?In lactic acid fermentation, pyruvate from glycolysis changes to lactic acid. This type of fermentation is carried out by the bacteria in yogurt, and by your own muscle cells. In alcoholic fermentation, pyruvate changes to alcohol and carbon dioxide. This type of fermentation is carried out by yeasts and some bacteria.
What is common between alcoholic fermentation and lactic acid formation?Complete answer: 1)Both alcoholic fermentation and lactic acid show similarities because they both are fermentation processes and both fermentation occurs in absence of oxygen.
How are lactic acid fermentation and alcoholic fermentation similar quizlet?Alcoholic Fermentation and Lactic Acid Fermentation are similar because they both need pyruvic acid and NADH to form. They are also similar because they both generate NAD+so that glycolysis can continue. But unlike Alcoholic Fermentation, Lactic Acid Fermentation does not give off carbon dioxide.
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