Mitochondria :: essays research papers

MitochondriaMitochondria are accountable for energy production. They are also theresponsible location for which respiration takes place. Mitochondria obligeenzymes that help convert food material into adenosine triphosphate (adenosine triphosphate), whichcan be apply 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 acids, can be furtheroxidized in the mitochondria. each(prenominal) mitochondrion is enclosed by two membranesseparated by an intermembrane outer space. The intermembrane space extends into thefolds of the versed 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 standardised t o 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 take in 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 muchsignificant 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 blow compound acetyl coenzyme A (acetyl CoA). Forpyruvate this involves a decarboxylation step which removes one of the tethercarbons of pyruvate as carbon dioxide. The energy released by the oxidation ofpyruvate at this tip i s used to reduce NAD to NADH. (185)The C2 acetyl CoA is then taken into a sequence of reactions known asKrebs steering wheel which completes the oxidation of carbon and regenerates an acceptorto cargo hold 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 couple to oxaloacetate, a C4 acceptor inthe cycle. The product is citrate a C6 compound. This first product, citrate,is the reasonableness the cycle is sometimes called the citric acid or ticarboxylic acidcycle, referring it after(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.