What is glycolysis?

• A. A catabolic process that breaks down carbohydrates and sugars in the cytoplasm through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP
• B. A process that requires oxygen to produce ATP in mitochondria
• C. The synthesis of proteins from amino acids
• D. The primary site of photosynthesis in plants

Answer: (A)

Glycolysis is the cytoplasmic breakdown of glucose through a sequence of enzyme-catalyzed steps that converts one glucose molecule into two pyruvate molecules. In the process, energy is captured as a net two ATP molecules and two NADH molecules. It does not require oxygen, so it can occur under anaerobic conditions, and the pyruvate produced can be shuttled into mitochondria for further oxidation when oxygen is present or, under low-oxygen conditions, reduced to lactate to regenerate NAD+. This description fits the option that describes glycolysis as a catabolic process in the cytoplasm turning carbohydrates into pyruvic or lactic acid with ATP production.