Biology Study Guides - SparkNotes
I. Reaction: C6H12O6 + 6O2 + 6H2O ——> 6CO2 + 12 H2O + energy (38 ATP and heat)
II. Aerobic Cellular Respiration occurs in three stages.
A. Glycolysis (occurs in the cytoplasm)
1. One glucose is split into two pyruvates (C3H4O3). 2. 4 ATP are produced, but 2 endergonic reactions use up 2 ATP. 3. Glycolysis requires no oxygen, and occurs whether oxygen is present or not. 4. Glycolysis occurs in all living cells.
5. Fermentation follows glycolysis in anaerobic conditions. a. Fermentation is not part of aerobic cellular respiration. b. Fermentation occurs in the cytoplasm. c. The purpose of fermentation is to prevent the accumulation of pyruvate, and to prevent the depletion of the NADox pool. d. There is more than one kind of fermentation. B. Krebs Cycle (occurs in the matrix of the mitochondria) 1. The Krebs cycle follows glycolysis in aerobic conditions (if the cell is capable of aerobic respiration). 2. It produces one ATP per pyruvate fed into the cycle. 3. It produces 4 NADred and 1 FADred for each pyruvate. 4. The Krebs Cycle uses no oxygen, but it can’t go if the ETS isn’t going, so it’s O2 dependent. 5. This cycle runs once per pyruvate, thus twice per glucose. 6. Per glucose, the Krebs Cycle produces 6 CO2 (discarded as waste in animal cells, recaptured for photosynthesis in plant cells). C. Electron Transport System (oxidative phosphoryllation) (occurs in the membranes of the cristae of the mitochondria) 1. The hydrogens on the reduced NAD’s and FAD’s are split into one H+ and one e- each. 2. The electrons are used to perform a series of reduction/oxidation chemical reactions which produce a lot of...