Question

The number of ATP molecules formed during aerobic respiration in the break down of one glucose molecule via the malate-aspartate shuttle is

• A. 38
• B. 18
• C. 28
• D. 4

Answer 1

The correct option is A 38

Number of ATP molecules formed during aerobic respiration in break down of one glucose molecule via malate aspartate shuttle is 38. The malate-aspartate shuttle is a biochemical system for translocating electrons produced during glycolysis across the semipermeable inner membrane of the mitochondrion for oxidative phosphorylation in eukaryotes. These electrons enter the electron transport chain of the mitochondria via reduction equivalents to generate ATP. The shuttle system is required because the mitochondrial inner membrane is impermeable to NADH, the primary reducing equivalent of the electron transport chain. To circumvent this, malate carries the reducing equivalents across the membrane.

Since the malate-aspartate shuttle regenerates NADH inside the mitochondrial matrix, it is capable of maximizing the number of ATPs produced in glycolysis (3/NADH), ultimately resulting in a net gain of 38 ATP molecules per molecule of glucose metabolized.