* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download 4.6 Fermentation
Lactate dehydrogenase wikipedia , lookup
Fatty acid synthesis wikipedia , lookup
NADH:ubiquinone oxidoreductase (H+-translocating) wikipedia , lookup
Metalloprotein wikipedia , lookup
Fatty acid metabolism wikipedia , lookup
Electron transport chain wikipedia , lookup
Light-dependent reactions wikipedia , lookup
Photosynthesis wikipedia , lookup
Basal metabolic rate wikipedia , lookup
Photosynthetic reaction centre wikipedia , lookup
15-Hydroxyeicosatetraenoic acid wikipedia , lookup
Adenosine triphosphate wikipedia , lookup
Specialized pro-resolving mediators wikipedia , lookup
Nicotinamide adenine dinucleotide wikipedia , lookup
Oxidative phosphorylation wikipedia , lookup
Evolution of metal ions in biological systems wikipedia , lookup
Citric acid cycle wikipedia , lookup
Butyric acid wikipedia , lookup
Microbial metabolism wikipedia , lookup
Fermentation Chapter 4: Cells and Energy Section 6: Fermentation Aerobic vs. Anaerobic • Cellular respiration is aerobic respiration – Two of the three phases of cellular respiration require oxygen • Which phase does NOT require oxygen? • The body cannot store large amounts of O2 – The amount of oxygen provided by breathing is enough to sustain cellular respiration during normal activities Aerobic vs. Anaerobic • But what happens when you are doing high levels of activity? – There is not enough oxygen to sustain cellular respiration despite breathing faster. How do cells make energy without oxygen? Aerobic vs. Anaerobic In the absence of oxygen, the cell will begin anaerobic respiration in order to produce chemical energy. • Recall: Glycolysis is an anaerobic process – Glycolysis is the breakdown of glucose – Glycolysis produces 2 pyruvates, 2 ATP and 2 NADH Fermentation • The production of ATP continues in anaerobic respiration through glycolysis and fermentation. • Fermentation- the process in which electrons are removed from NADH to create NAD+ molecules – Does not make ATP – Instead, the purpose of fermentation is to allow glycolysis to continue Glycolysis and Fermentation Why does glycolysis need fermentation in order to continue? • Glycolysis needs an electron carrier molecule – Without NAD+, glycolysis would stop – By picking up high, energy electrons, a eukaryotic cell can continue to break down glucose for a small amount of ATP Fermentation There are two types of fermentation: 1. Lactic Acid Fermentation 2. Alcoholic Fermentation Lactic Acid Fermentation • Lactic Acid Fermentation – Occurs in muscle cells, cells of other vertebrates and some microorganisms – Lactic acid (C3H6O3) • Causes your muscles to “burn” during hard exercise Lactic Acid Fermentation Steps of Lactic Acid Fermentation: 1. Pyruvate and NADH from glycolysis enter the fermentation process. Two NADH molecules provide energy to convert pyruvate into lactic acid. 2. Two molecules of NAD+ are recycled back to glycolysis Lactic Acid Fermentation Lactic Acid Fermentation • By itself, fermentation does not produce ATP – Instead, it removes H+ and electrons from NADH – The NAD+ is then able to be returned to glycolysis, where 2 ATP are made • During lactic acid fermentation, lactic acid builds up in muscle cells – When O2 becomes available, cellular respiration begins again, quickly breaking down lactic acid • This is why you breathe hard for several minutes for several minutes after you stop exercising Alcoholic Fermentation • Alcoholic Fermentation – Occurs in many yeasts and some types of plants Alcoholic Fermentation Steps of Alcoholic Fermentation: 1. Pyruvate and NADH from glycolysis enter the fermentation process. Two NADH molecules provide the energy needed to break pyruvate into an alcohol and CO2 2. Two molecules of NAD+ are recycled back to glycolysis Alcoholic Fermentation Alcoholic Fermentation • Often the alcohol produced is ethyl alcohol Alcoholic Fermentation Example of Alcoholic Fermentation: • Yeast is used to cause bread to rise – Sugars in dough are broken down through glycolysis – The resulting release of CO2 causes the bread to puff up – The alcohol produced evaporates during baking – The yeast is killed by the heat.