Cellular Respiration

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Cellular Respiration Diagram

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Glycolysis
Glycolysis literally means "-splitting." In glycolysis, the -carbon sugar glucose is split into molecules of pyruvate, also called acid. This process produces a net gain of ATP molecules. The resulting molecules of pyruvate each have carbon atoms. Glycolysis takes place in the cell's . The remainder of cellular respiration takes place in organelles called .
The Krebs Cycle
The Krebs Cycle takes place in the fluid-filled area inside the inner membrane of the mitochondria known as the . Some and other energy carrying molecules are produced here. The gas is a byproduct of this process.
The Electron Transport Chain
Most of the is produced in this last step of cellular respiration. Electron transport takes place in the infoldings of the inner-membrane of the mitochondria. These infoldings are called . At the end of electron transport, combines with hydrogen ions and (e-) to form .
½O2 + 2H+ + 2e- → H2O
Overall Process
glucose + oxygen → carbon dioxide + water + 38
Fermentation
In the absence of , the cell resorts to anaerobic metabolism. In animal cells, pyruvate is converted to acid. In yeast and bacteria, the pyruvate is often converted to . In both cases, no new ATP is produced, so the net production of the -carrying molecule is only the molecules of ATP produced in glycolysis.