* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Cellular Respiration
Survey
Document related concepts
Evolution of metal ions in biological systems wikipedia , lookup
NADH:ubiquinone oxidoreductase (H+-translocating) wikipedia , lookup
Adenosine triphosphate wikipedia , lookup
Butyric acid wikipedia , lookup
Photosynthesis wikipedia , lookup
Electron transport chain wikipedia , lookup
Photosynthetic reaction centre wikipedia , lookup
Light-dependent reactions wikipedia , lookup
Microbial metabolism wikipedia , lookup
Oxidative phosphorylation wikipedia , lookup
Citric acid cycle wikipedia , lookup
Transcript
Cellular Respiration Mitochondria Mitochondria are membrane-enclosed found in the cytoplasm of eukaryotic cells. Their number within the cell ranges from a few hundred to, in very active cells, thousands. Their main function is the conversion of the potential energy of food molecules into ATP. Mitochondria have: • an outer membrane that encloses the entire structure • an inner membrane that encloses a fluid-filled matrix • the inner membrane is folded with shel-flike cristae projecting into the matrix. • a small number of circular DNA Overview of Cellular Respiration Cellular respiration is the process that releases energy by breaking down glucose and other food molecules in the presence of oxygen. Copyright Pearson Prentice Hall Overview of Cellular Respiration Electrons carried in NADH Pyruvic acid Glucose Electrons carried in NADH and FADH2 Glycolysis Cytoplasm Mitochondrion Copyright Pearson Prentice Hall Overview of Cellular Respiration The equation for cellular respiration is: 6O2 + C6H12O6 → 6CO2 + 6H2O + Energy oxygen + glucose → carbon dioxide + water + Energy Copyright Pearson Prentice Hall Overview of Cellular Respiration Glycolysis takes place in the cytoplasm. The Krebs Cycle and electron transport take place in the mitochondria. Glycolysis Cytoplasm Mitochondrion Copyright Pearson Prentice Hall Glycolysis • During glycolysis, glucose is broken down into 2 molecules of pyruvate and 2 ATP. • Takes place in the cytoplasm • Anaerobic-no oxygen is used The Advantages of Glycolysis The process of glycolysis is so fast that cells can produce thousands of ATP molecules in a few milliseconds. Fermentation When oxygen is not present, glycolysis is followed by a different pathway. The combined process of this pathway and glycolysis is called fermentation. Fermentation releases energy from food molecules by producing ATP in the absence of oxygen. Copyright Pearson Prentice Hall Fermentation What are the two main types of fermentation? Copyright Pearson Prentice Hall Fermentation Alcoholic Fermentation Yeasts and a few other microorganisms use alcoholic fermentation, forming ethyl alcohol and carbon dioxide as wastes. The equation for alcoholic fermentation after glycolysis is: pyruvic acid + NADH → alcohol + CO2 + NAD+ Copyright Pearson Prentice Hall Lactic Acid Fermentation In many cells, pyruvic acid that accumulates as a result of glycolysis can be converted to lactic acid. This type of fermentation is called lactic acid fermentation. It regenerates NAD+ so that glycolysis can continue. The equation for lactic acid fermentation after glycolysis is: pyruvic acid + NADH → lactic acid + NAD+ Copyright Pearson Prentice Hall Fermentation The first part of the equation is glycolysis. Copyright Pearson Prentice Hall Fermentation The second part shows the conversion of pyruvic acid to lactic acid. Copyright Pearson Prentice Hall 9-2 The Krebs Cycle and Electron Transport Oxygen is required for the final steps of cellular respiration. Because the pathways of cellular respiration require oxygen, they are aerobic. Copyright Pearson Prentice Hall The Krebs Cycle What happens during the Krebs cycle? Copyright Pearson Prentice Hall The Krebs Cycle During the Krebs cycle, pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions. Copyright Pearson Prentice Hall The Krebs cycle begins when pyruvic acid produced by glycolysis enters the mitochondrion. Pyruvic acid will be converted into Citric Acid using high forms of energy. Citric acid Copyright Pearson Prentice Hall Electron Transport How are high-energy electrons used by the electron transport chain? Copyright Pearson Prentice Hall Electron Transport Electron Transport The electron transport chain uses the high-energy electrons from the Krebs cycle to convert ADP into ATP. Copyright Pearson Prentice Hall Electron Transport High-energy electrons are passed along the electron transport chain from one carrier protein to the next. Copyright Pearson Prentice Hall Electron Transport At the end of the chain, an enzyme combines these electrons with hydrogen ions and oxygen to form water. Copyright Pearson Prentice Hall The Totals The Totals Glycolysis produces just 2 ATP molecules per molecule of glucose. The complete breakdown of glucose through cellular respiration, including glycolysis, results in the production of 36 molecules of ATP. Copyright Pearson Prentice Hall The Totals Copyright Pearson Prentice Hall Comparing Photosynthesis and Cellular Respiration Comparing Photosynthesis and Cellular Respiration The energy flows in photosynthesis and cellular respiration take place in opposite directions. Copyright Pearson Prentice Hall • http://vimeo.com/10693405