Substrate-level phosphorylation directly generates ATP during a chemical reaction. As a single molecule of glucose is completely oxidized, in the presence of oxygen, how many molecules of ATP are gained by substrate-level phosphorylation? a) 6 ATPb) 4 ATPc) 2 ATPd) 38 ATP

B) 4 ATP

Explanation:

The most favoured substrate of the cellular respiration is called glucose which on complete oxidation yields ATP.

The substrate level of phosphorylation is the formation of the ATP molecules from a phosphorylated intermediate and the ADP.

During glycolysis, the substrate-level phosphorylation produces 4 ATP molecules out of which 2 molecules are utilized during the process itself thus there is a net gain of glycolysis produces 2 ATP molecules.

Thus, 4 ATP is the correct answer.