CP Bio: Cell Respiration - Review Topics
Introduction
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Energy in cells, ATP- ADP cycle
Aerobic and anaerobic – organisms, pathways, energy yield
Compare to photosynthesis: reactants, products, energy
Gas exchange, glucose delivery to cells
Calorie, amount in carbs, fats, and proteins
Mitochondria – compartments, sites for reactions
NAD, FAD - Hydrogen/electron acceptors, how they help
pathways – where in cell, energy made
Aerobic Respiration
Glycolysis - In cytoplasm
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Use 2 ATP; glucose splits
Form 2 pyruvic acid (3 C each)
Make 4 ATP, make NADH
Net yield: 2 ATP
Krebs Cycle (Citric Acid cycle)
 In mitochondrial matrix
Prep: pyruvic acid  acetyl CoA (2C) + CO2
Cycle: Finishes glucose breakdown
 Acetyl  2 CO2
 NAD FAD take H+ and e 2 ATP per glucose, 1 each cycle
Electron Transport Chain – In cristae
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NADH and FADH release H+ and ee- pass to series of proteins in membrane
energy from electrons makes ATP
oxygen + electrons + hydrogen  water
Yield: 32 ATP
Total ATP from one glucose = 36 ATP
Amatuzzi
Anaerobic Respiration – when oxygen is absent
 in cytoplasm
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Glycolysis is followed by fermentation
No additional ATP made (2 made in glycolysis)
NAD+ is returned, can be used again
Lactic acid Fermentation: pyruvic acid  lactic
acid (or other acids)
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Some bacteria
Muscle cells – only temporarily
o Oxygen debt – muscles cramp and burn – need oxygen
Alcohol Fermentation: pyruvic acid  alcohol + CO2
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Yeast – baking, brewing beer
Makes ethyl alcohol and CO2
36 ATP
Other Foods can be broken down for energy, but carbs are first choice (4cal/g)
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Proteins – last choice - make nitrogen/ammonia waste, stress kidneys and liver
Foods NOT used for energy
 raw materials to make other biologic molecules in synthesis