AP BIOLOGY

Detailed explanation-1: -Pyruvate, derived from glycolysis, is firstly converted into acetyl-CoA (2-C) which is subsequently condensed with oxaloacetate (4-C) to form the 6-C compound citrate. This is cycled back to oxaloacetate via a series of reactions which form CO2 (as a waste product) as well as NADH and FADH.

Detailed explanation-2: -In order for pyruvate, the product of glycolysis, to enter the next pathway, it must undergo several changes to become acetyl Coenzyme A (acetyl CoA). Acetyl CoA is a molecule that is further converted to oxaloacetate, which enters the citric acid cycle (Krebs cycle).

Detailed explanation-3: -Pyruvate, the product from glycolysis, is transformed into acetyl CoA in the mitochondria for the next step. The citric acid cycle, where acetyl CoA is modified in the mitochondria to produce energy precursors in preparation for the next step.

Detailed explanation-4: -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.

Detailed explanation-5: -In order to enter the Kreb’s Cycle pyruvate must first be converted into Acetyl-CoA by pyruvate dehydrogenase complex found in the mitochondria.