AP BIOLOGY

Detailed explanation-1: -Pyruvate-three carbons-is converted to acetyl CoA, a two-carbon molecule attached to coenzyme A . A molecule of coenzyme A is a necessary reactant for this reaction, which releases a molecule of carbon dioxide and reduces a NAD+ to NADH.

Detailed explanation-2: -Link reaction or transition reaction is important because it connects the glycolysis with the Krebs cycle by producing acetyl CoA (coenzyme A) which is a substrate for the Krebs cycle. Aerobic respiration involved three stages which are glycolysis, Krebs cycle, and the electron transport chain (ETC).

Detailed explanation-3: -Upon entering the mitochondrial matrix, a multi-enzyme complex converts pyruvate into acetyl CoA. In the process, carbon dioxide is released and one molecule of NADH is formed.

Detailed explanation-4: -The link reaction takes place in the mitochondrial matrix and converts pyruvate into a molecule called acetyl coenzyme A (acetyl CoA). This stage does not produce any energy in the form of ATP but does produce reduced NAD and acetyl CoA.

Detailed explanation-5: -Complete answer: The correct answer is Oxidative decarboxylation. Decarboxylation or oxidative decarboxylation reaction is the biochemical reaction which uses pyruvate in order to form acetyl-CoA, by releasing NADH, which is a reducing equivalent, and carbon dioxide upon decarboxylation.