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Cellular Respiration Chapter 7-1. Organic compounds are broken down to release energy, as in ATP!. Begins with Glycolysis. If oxygen = aerobic respiration 1. Kreb's cycle 2. Electron transport. If no oxygen = fermentation - lactic acid - alcoholic.
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Cellular Respiration Chapter 7-1 Organic compounds are broken down to release energy, as in ATP! Begins with Glycolysis If oxygen = aerobic respiration 1. Kreb's cycle 2. Electron transport If no oxygen = fermentation - lactic acid - alcoholic
7-1 Glycolysis and Fermentation Harvesting Chemical Energy Cellular respiration is a process in which cells make ATP by breaking down organic compounds (like those made by Photosynthesis). Glycolysis: a biochemical pathway, which yields a small amount of ATP. The products of glycolysis can then go one of two ways.
Use your textbook, pg. 128 to fill in this Glycolysis diagram. Briefly list steps: 1. 2. 3. 4. glycolysis
Fermentation (Anaerobic Pathway - in the absence of oxygen) 2 types • Lactic Acid Fermentation:an enzyme converts pyruvic acid into a 3-carbon compound, lactic acid.
Alcoholic Fermentation:pyruvic acid is converted into ethyl alcohol. Pathway has 2 steps. Note: A CO2 molecule is removed in the first step; think yeast cells and bread baking!
Energy Yield How efficient are anaerobic pathways? Not very! Pathway evolved early, common for bacteria and single-celled organisms. anaerobic respiration
Section 7-1 Review • 1. DefineCellular Respiration. • 2. What six-carbon molecule begins glycolysis, an what three-carbon molecules are produced at the end of glycolysis? • 3. For each six-carbon molecule that begins glycolysis, how many ATP molecules are used and how many ATP molecules are produced? • 4. What condition must exist in a cell for the cell to engage in fermentation? • 5. How efficient is glycolysis?