Concept 9.2: Glycolysis harvests chemical energy by oxidizing glucose to pyruvate

Flashcards from Concept 9.2 of Pearson's Campbell Biology, Twelfth Edition.

Glycolysis

The breakdown of one glucose molecule to two molecules of pyruvate that occurs in the cytoplasm

• Creates two net ATP molecules by substrate-level phosphorylation

  • Done through an energy investment and energy payoff phase

• Does not release any CO₂, occuring whether or not O₂ is present

Energy investment phase

The first phase of glycolysis, splitting glucose into two three-carbon sugar molecules (G3P) using 2 molecules of ATP

Glyceraldehyde 3-phosphate (G3P)

The three-carbon sugar molecule that glucose is initially broken into two of in the energy investment phase using 2 molecules of ATP

Energy payoff phase

The second phase of glycolysis

• Synthesizes 4 molecules of ATP

• Reduces 2 NAD+ to NADH

• Oxidizes the small sugars to create 2 pyruvate and 2 H₂O