Cellular Respiration: Harvesting Chemical Energy
5191368992 | Fermentation | -catabolic process that partially degrades sugars w/o oxygen -expansion of glycolysis that allows continuous generation of ATP by substrate-level phosphorylation of glucose -regenerates NAD+ by transferring electron from NADH to pyruvate -produce ATP by harvesting chemical energy of food -use glycolysis to oxidize glucose and other organic fuels to pyruvate-net production of 2 ATP w/ substrate level phosphorylation -NAD+ is oxidizing agent that accepts electrons from food in glycolysis -final electron acceptor is organic molecule | ![]() | 0 |
5191368993 | Aerobic Respiration | -oxygen consumed as reactant along w/ organic fuel -prokaryotes and eukaryotes -produce ATP by harvesting chemical energy of food -use glycolysis to oxidize glucose and other organic fuels to pyruvate-net production of 2 ATP w/ substrate level phosphorylation -NAD+ is oxidizing agent that accepts electrons from food in glycolysis -final electron acceptor is NADH is oxygen-regenerates NAD+ for glycolysis, pays ATP bonus when electron transport from NADH -> O2 drives oxidative phosphorylation -citric acid cycle-oxidation of pyruvate bigger ATP pay off -19x more energy/sugar molecule | ![]() | 1 |
5191368994 | Anaerobic Respiration | -process of using substances other than oxygen as reactants to harvest chemical energy w/o oxygen -use electron transport chain but don't use oxygen as final electron acceptor | 2 | |
5191368995 | Cellular Repsiration | -process for animal to breathe oxygen; aerobic + anaerobic -C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP + heat) | ![]() | 3 |
5191368996 | Redox Reactions | reactions w/ electron transfer | 4 | |
5191368997 | Oxidation | loss of electrons from one substance | 5 | |
5191368998 | Reduction | addition of electrons to another substance | 6 | |
5191368999 | Reducing Agent | electron donor | 7 | |
5191369000 | Oxidizing Agent | electron acceptor | 8 | |
5191369001 | NAD+ | -coenzyme electron acceptor -oxidizing agent in respiration | 9 | |
5191369002 | Glycolysis | -begins degradation process by breaking glucose into 2 pyruvate molecules +2 ATP w/ substrate-level phosphorylation | ![]() | 10 |
5191369003 | Citric Acid Cycle | -completes breakdown of glucose by oxidizing pyruvate to CO2 -CO2 produced represents fragments of oxidized organic molecules -takes place in mitochondrial matrix (eukaryotic) /cytosol (prokaryotic) +2 w/ substrate-level phosphorylation | ![]() | 11 |
5191369004 | Acetyl CoA | junction between glycolysis and citric acid cycle 1. pyruvate's carboxyl group (-COO-) removed and given of as molecule of CO2 2. remaining 2-carbon fragment oxidized -> acetate. enzyme transfers extracted electrons to NAD+, storing energy in form of NADH 3. coenzyme A attached to acetate by unstable bond that makes acetyl group very reactive -> acetyl CoA has high potential energy-reaction to yield lower energy products is highly exergonic | ![]() | 12 |
5191369005 | Oxidative Phosphorylation | -mode of ATP synthesis powered by redox reactions in electron transport chain-energy released at each step of chain stored in form for mitochondria -90% of ATP generated +32-34 ATP by oxidative phosphorylation | ![]() | 13 |
5191369006 | Electron Transport Chain | breaks fall of electrons to oxygen in energy releasing steps -consists of molecules (proteins) in inner membrane (eukaryote)/plasma membrane (prokaryote) | 14 | |
5191369007 | Cytochromes | most of remaining electron carriers | 15 | |
5191369008 | ATP Synthase | -enzyme in inner membrane of mitochondrion that makes ATP from ADP and inorganic protein -ion pump running in reverse -uses energy of existing ion gradient to power ATP synthesis | 16 | |
5191369009 | Chemiosmosis | -process in which energy stored as H+ gradient across membrane used to drive cellular work like ATP synthesis -protons move one by one to binding sites of ATP synthase -> spins in way to catalyze production of ATP from ADP and inorganic phosphatwe | ![]() | 17 |
5191369010 | Substrate-Level Phosphorylation | mode of ATP synthesis when enzyme transfers phosphate group from substrate molecule to ADP, rather than adding inorganic phosphate to ADP | 18 | |
5191369011 | Proton-motive Force | H+ gradient and its capacity to do work | 19 | |
5191369012 | Alcohol Fermentation | -pyruvate converted to ethanol 1. CO2 released from pyruvate-converted to 2-carbon acetaldehyde 2. acetaldehyde reduced by NADH to ethanol-regenerates supply of NAD+ for glycolysis | 20 | |
5191369013 | Lactic Acid Fermentation | -pyruvate reduced directly by NADH -> form lactate w/ no release of CO2 -sugar catabolism for ATP production outpaces muscle's supply of oxygen -> cells switch from aerobic respiration to fermentation | 21 | |
5191369014 | Obligate Anaerobes | organisms that only carry out fermentation or anaerobic respiration-cannot survive in presence of oxygen | 22 | |
5191369015 | Facultative Anaerobes | -make enough ATP to survive using fermentation or respiration -pyruvate -> 2 alternative catabolic rates -aerobic conditions: pyruvate -> acetyl CoA-oxidation continues in Krebs Cycle -anaerobic conditions: pyruvate diverted from Krebs Cycle-serves as electron acceptor to recycle NAD+ - has to consume sugar at faster rate | 23 |