Glycolysis

In-depth explanation of Glycolysis

Glycolysis is a ten-step pathway in the cytosol that breaks one glucose molecule into two molecules of pyruvate, and it does not require oxygen. The first steps invest two ATP to phosphorylate glucose and cleave the six-carbon sugar into two three-carbon units. Later steps generate four ATP and two NADH through substrate-level phosphorylation and the oxidation of glyceraldehyde-3-phosphate, so the net yield is two ATP and two NADH per glucose. The key regulated step is catalysed by phosphofructokinase, which is inhibited by ATP and activated by AMP. Under anaerobic conditions pyruvate is converted to lactate or ethanol to regenerate NAD+.

Going deeper: Glycolysis

Key ideas: Ten steps in cytosol convert glucose (6C) to two pyruvate (3C). Investment phase uses 2 ATP, payoff phase makes 4 ATP and 2 NADH, net 2 ATP and 2 NADH per glucose. Key regulated step is phosphofructokinase. Needs no oxygen.

Common mistakes and connections: Mistake: giving net ATP as 4; two are consumed. Another is saying it happens in mitochondria. Substrate-level phosphorylation makes the ATP here, unlike oxidative phosphorylation. Links to fermentation (regenerating NAD+), Krebs cycle and the Warburg effect in tumors.

Visualization of Glycolysis

Glycolysis per glucose spends 2 ATP, makes 4, and nets 2 ATP plus 2 NADH while splitting glucose into two pyruvate. The interactive lesson shows this as a live animation or chart.

Worked example and use case

In simplified form, glucose + 2 NAD+ + 2 ADP + 2 Pi gives 2 pyruvate + 2 NADH + 2 ATP.

Where Glycolysis fits in Biochemistry, Environment & Industry

Glycolysis is topic 33 of 127 in Biochemistry, Environment & Industry.

Related topics

• CRISPRAdvanced
• MetabolismIntermediate
• ATPBeginner
• Krebs CycleAdvanced
• Oxidative PhosphorylationAdvanced
• PhotosynthesisBeginner

Browse all 127 topics in Biochemistry, Environment & Industry