Mitochondria :: essays research papers

MitochondriaMitochondria are responsible for(p) for energy production. They are also theresponsible location for which respiration takes place. Mitochondria selectenzymes that help convert food material into adenosine triphosphate (adenosine triphosphate), whichcan be use directly by the cell as an energy source. Mitochondria tend to beconcentrated near cellular structures that require large inputs of energy, suchas the flagellum. The role of the mitochondria is very important in respiration.In the presence of oxygen, pyruvate or fat person acids, can be furtheroxidized in the mitochondria. from each one mitochondrion is enclosed by two membranesseparated by an intermembrane plaza. The intermembrane space extends into thefolds of the inner(a) membrane called cristae which dramatically increase thesurface area of the inner membrane. Cristae extend into a dense material calledthe matrix, an area which contains RNA, DNA, proteins, ribosomes and range ofsolutes. This is sympathet ic to the contents of the chloroplast stroma and like thechloroplast, the mitochondrion is a semi-autonomous organelles containing themachinery for the production of some of its get proteins. The main function ofthe mitochondrion is the oxidation of the pyruvate derived from glycolysis andrelated processes to produce the ATP required to perform cellular work.(Campbell182-9)Pyruvate, or fatty acids from the breakdown of triglycerides orphospholipids, pass easily through pores in the outer mitochondrial membrane do up of a channel protein called porin. The inner membrane is a more thansignificant barrier and specific transport proteins exist to carry pyruvate andfatty acids into the matrix. Once inside the matrix, pyruvate and fatty acidsare converted to the two coulomb compound acetyl coenzyme A (acetyl CoA). Forpyruvate this involves a decarboxylation step which removes one of the threecarbons of pyruvate as carbon dioxide. The energy released by the oxidation ofpyruvate at this full stop is used to reduce NAD to NADH. (185)The C2 acetyl CoA is then taken into a sequence of reactions known asKrebs pedal which completes the oxidation of carbon and regenerates an acceptorto bear the cycle going. The oxidation of the carbon is accompanied by thereduction of electron acceptors and the production of some ATP by substratephosphorylation. The C2 acetyl CoA is pair to oxaloacetate, a C4 acceptor inthe cycle. The product is citrate a C6 compound. This first product, citrate,is the movement the cycle is sometimes called the citric acid or ticarboxylic acidcycle, referring it aft(prenominal) the scientist whose lab most advanced ourunderstanding of it, Sir Hans Krebs. (Comptons 160)Two of the early reactions of the cycle are decarboxylations whichshorten citrate to succinate a C4 compound.