Goal: break glucose down to form two pyruvates
Where in the cell: the cytosol
Cells harvest the energy contained in the chemical bonds of glucose in a very controlled, step-by-step series of reactions that release small amounts of energy during each reaction. Glycolysis is the first step of cellular respiration, where a molecule of glucose is split to release energy. Glycolysis occurs in the cytosol of the cell and does not require oxygen (can occur when aerobic or anaerobic conditions exist). Ten enzymes participate in this metabolic pathway.
In glycolysis, glucose with six carbons is converted into two molecules of pyruvate, each with three carbons. In the summary of glycolysis below, glucose converts to two molecules of pyruvate,yielding 2 ATP and 2 NADH.
Products: In the end, one molecule of glucose is broken down into 2 pyruvate molecules with energy transfer to form a net production of 2 ATP molcules and 2 NADH molecules.
Note that glycolysis produces 4 ATP's and 2 NADH, but uses 2 ATP's in the process for a net of 2 ATP and 2 NADH as seen below in an overview of energy
investment/liberation during glycolysis:
Click on the link below to view a brief tutorial of Glycolysis:
Click on the link below to view an animation of Glycolysis: