What is the net yield of ATP when one molecule of glucose is converted completely to two molecules of lactate in a red blood cell?

• A 8 ATP
• B 6 ATP
• C 4 ATP
• D 2 ATP ✓

Explanation

Glycolysis consumes 2 ATP at hexokinase and phosphofructokinase-1 steps and generates 4 ATP by substrate-level phosphorylation at phosphoglycerate kinase and pyruvate kinase, giving a net of 2 ATP. In the red cell there is no mitochondrion, so oxidative phosphorylation cannot add anything. The figure of 4 is gross ATP production before subtracting the two invested ATP molecules.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.