Which component is NOT a product of glycolysis?

Glycolysis is the metabolic pathway that breaks down glucose to extract energy for cellular metabolism. At the end of glycolysis, the primary products formed are two molecules of pyruvate, two NADH molecules, and a net gain of two ATP molecules.

When considering the products from glycolysis, it is essential to note that while glycolysis produces four ATP molecules overall, there is a net production of only two ATP molecules because two ATPs are consumed in the initial steps of the pathway. Therefore, although four ATP molecules are produced during the process, the distinction is made that only two are available for use after accounting for the initial investment of ATP.

In this context, the option that states "4 ATP" does not correctly represent the net product of glycolysis, making it the right choice for the component that is not a product of glycolysis in terms of ATP count.