AP BIOLOGY

Detailed explanation-1: -Glycolysis can generate ATP in the absence of oxygen. This is described as anaerobic metabolism. It results from substrate-level phosphorylation. This is distinct from oxidative phosphorylation that occurs in the mitochondria.

Detailed explanation-2: -Substrate-level phosphorylation is the production of ATP from ADP by a direct transfer of a high-energy phosphate group from a phosphorylated intermediate metabolic compound in an exergonic catabolic pathway.

Detailed explanation-3: -In working skeletal muscles and the brain, Phosphocreatine is stored as a readily available high-energy phosphate supply, and the enzyme creatine phosphokinase transfers a phosphate from phosphocreatine to ADP to produce ATP.