In this lecture, I'd like to focus on the anaerobic process. The anaerobic process takes place in the absence of oxygen. And our own cells and many other cells in nature use this specific type of process that we call fermentation. Now, there are many different examples of fermentation processes. But the most common fermentation processes are those that produce lactate or ethanol from the pyruvate molecules. So these are known as ethanol fermentation or alcoholic fermentation or in the case of producing lactate which is actually the conjugate base of lactic acid.