Which metabolic pathway converts glucose into pyruvate?

Glycolysis is the metabolic pathway that converts glucose into pyruvate. This process occurs in the cytoplasm of cells and involves a series of ten enzymatic reactions that break down glucose, a six-carbon sugar, into two molecules of pyruvate, which is a three-carbon compound.

During glycolysis, glucose is phosphorylated and eventually split into two molecules of glyceraldehyde-3-phosphate (G3P), which are then oxidized and converted into pyruvate. The pathway also yields a net gain of two molecules of ATP and two molecules of NADH, which are important energy carriers in cellular metabolism.

In contrast, the Kreb cycle (also known as the citric acid cycle) occurs after glycolysis and processes pyruvate into carbon dioxide, while the Calvin cycle is part of photosynthesis where carbon fixation occurs, and the light reaction is a process in photosynthesis that captures light energy but does not directly involve glucose or pyruvate. Thus, glycolysis is specifically responsible for the initial breakdown of glucose into pyruvate.