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(Cellular Respiration) BY Chantel Richardson and Hunter Kratochvil
Cellular respiration is the process by which the chemical energy of "food" molecules is released and partially captured in the form of ATP. Carbohydrates, fats, and proteins can all be used as fuels in cellular respiration, but glucose is most commonly used as an example to examine the reactions and pathways involved. It takes place in both prokaryotic and eukaryotic cells. You have two different kinds of repiration Aerobic and Anaerobic, Anaerobic repiration may also be called Fermentation.
Aerobic Respiration has three stages:

CELLULAR RESPIRATION (Cellular Respiration)
Cellular respiration is the process by which the chemical energy of "food" molecules is released and partially captured in the form of ATP. Carbohydrates, fats, and proteins can all be used as fuels in cellular respiration, but glucose is most commonly used as an example to examine the reactions and pathways involved. It takes place in both prokaryotic and eukaryotic cells. You have two different kinds of repiration Aerobic and Anaerobic, Anaerobic repiration may also be called Fermentation.
Aerobic Respiration has three stages:

ANAEROIBIC RESPIRATION
Anaerobic respiration
is a form of respiration using electron acceptors other than oxygen. Although oxygen is not used as the final electron acceptor, the process still uses a respiratory electron transport chain; it is resperation without oxygen. In order for the electron transport chain to function, an exogenous final electron acceptor must be present to allow electrons to pass through the system. In aerobic organisms, this final electron acceptor is oxygen. Molecular oxygen is highly oxidizing and therefore is an excellent acceptor. In anaerobes, other less oxidizing substances such as sulfate (SO42-), nitrate (NO3-) or sulfur (S) are used. These terminal electron acceptors have smaller reduction potentials than O2, meaning that less energy is released per oxidized molecule. Anaerobic respiration is therefore generally energetically less efficient than aerobic respiration.
{http://www.methuen.k12.ma.us/mnmelan/fermentation.jpg}

anKrebs Cycle
Krebs Cycle begins after the two molecules of the three carbon sugar produced in glycolysis are converted to a slightly different compound (acetyl CoA). Through a series of intermediate steps, several compounds capable of storing "high energy" electrons are produced along with two ATP molecules. These compounds, known as nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD), are reduced in the process. These reduced forms carry the "high energy" electrons to the next stage.
{http://drchadedwards.com/wp-content/uploads/2010/02/krebs_cycle1.gif}
Electron Transport
An electron transport
{http://www.uni-konstanz.de/FuF/Bio/AGBrdiczka/ns/graphics/chapter1/1_4.gif}

||~ Step ||~ coenzyme yield ||~ ATP yield ||~ Source of ATP || || Glycolysis preparatory phase || || -2 || Phosphorylation of glucose and fructose 6-phosphate uses two ATP from the cytoplasm. || || Glycolysis pay-off phase || || 4 || Substrate-level phosphorylation || ||^ || 2 NADH || 4 || Oxidative phosphorylation - Each NADH produces net 2 ATP due to NADH transport over the mitrochondrial membrane || || Oxidative decarboxylation of pyruvate || 2 NADH || 6 || Oxidative phosphorylation || || Krebs cycle || || 2 || Substrate-level phosphorylation || ||^ || 6 NADH || 18 || Oxidative phosphorylation || ||^ || 2 FADH2 || 4 || Oxidative phosphorylation || |||| Total yield || 36 ATP || From the complete oxidation of one glucose molecule to carbon dioxide and oxidation of all the reduced coenzymes. ||
ANAEROIBIC RESPIRATION
Anaerobic respiration

||~ Step ||~ coenzyme yield ||~ ATP yield ||~ Source of ATP || || Glycolysis preparatory phase || || -2 || Phosphorylation of glucose and fructose 6-phosphate uses two ATP from the cytoplasm. || || Glycolysis pay-off phase || || 4 || Substrate-level phosphorylation || ||^ || 2 NADH || 4 || Oxidative phosphorylation - Each NADH produces net 2 ATP due to NADH transport over the mitrochondrial membrane || || Oxidative decarboxylation of pyruvate || 2 NADH || 6 || Oxidative phosphorylation || || Krebs cycle || || 2 || Substrate-level phosphorylation || ||^ || 6 NADH || 18 || Oxidative phosphorylation || ||^ || 2 FADH2 || 4 || Oxidative phosphorylation || |||| Total yield || 36 ATP || From the complete oxidation of one glucose molecule to carbon dioxide and oxidation of all the reduced coenzymes. ||
ANAEROIBIC RESPIRATION
Anaerobic respiration