What are the key differences between fermentation and glycolysis in terms of their metabolic processes and end products?

Fermentation and glycolysis are both metabolic processes that break down glucose to produce energy. The key difference is that glycolysis occurs in the absence of oxygen, while fermentation occurs in the presence of oxygen. In glycolysis, glucose is broken down into pyruvate, which can then be further metabolized in the presence of oxygen. In fermentation, pyruvate is converted into different end products, such as lactic acid or ethanol, to regenerate NAD for continued glycolysis in the absence of oxygen.