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Everything You Need To Know About Cellular Respiration

Transition Reaction

What Is Cellular Respiration?
Transition Reaction
Krebs Cycle
Electron Transport Chain

      The Transition Reaction converts the two molecules of the 3-carbon pyruvate from glycolysis into two molecules of the 2-carbon molecule acetyl Coenzyme A (acetyl-CoA).

       Transition Reaction is also called Oxidative Decarboxylation. It takes place in the matrix of the mitochondria. It is the beginning of aerobic respiration, meaning this phase will continue to take place as long as there is a sufficient amount of oxygen available in the mitochondria. If there is not then the process of fermentation will begin.

       At the beginning of Transition Reaction pyruvate pierces or penetrates the external mitochondrial membrane. It then goes into the matrix by a protein located on the external membrane. Now that its in the matrix a complex called pyruvate - dehydrogenase (enzyme) aids the process of Oxidative Decarboxylation. NAD+ acquires two electrons that breaks down pyruvate releasing CO2. A two carbon molecule called acetyl that bonds instantly with a coenzyme called coenzyme A to form acetyl Co- A. This coenzyme A is a compound that has an active group that is synthesized through the ingestion of vitamin B.

      Acetyl Co - A is made because it is essential ingredient to the next phase, Krebs Cycle, At this point in transition Reaction sugars can supply the needed acetyl to make ATP or acetyl Co - A can form through fat and protein decomposition. If the ATP level is too high, the acetyl Co - A is sent to another metabolic pathway such as the production of fatty acids, in the production of fats.

Cellular Respiration