Before the cells of our body, such as liver cells or skeleton muscle cells, can actually use their supply of glucose. They have to release the glucose from glycogen because inside our body we store glucose in the form we call glycogen. So the question that I would like to address in this lecture is how exactly do we break down glycogen inside the cells of our body? Well, glycogen, glycogen breakdown, also known as glycogen degradation, is the process by which we carry out three different steps to basically release the glucose molecule from glycogen. And this process actually involves four different enzymes, as we'll see in just a moment. So let's discuss the first step of glycogen breakdown.