Carbohydrate metabolism starts with digestion in the small intestines. This is the site where monosaccharides are absorbed into the blood stream. This type of metabolism is basically considered to be glucose metabolism because carbohydrates are eventually broken down into glucose so that it can diffuse into the blood stream.
There are three hormones in the body that control the concentration on glucose in the body: Insulin, glucagon, and epinephrine. If sugars are too high in the body, the pancreas will secrete the hormone insulin to stimulate the transfer of the glucose into cells, such as muscle and liver. Although glucose can be metabolized in many places, it is the muscles and the liver that can metabolize it more easily. The breakdown of glucose in the body happens in 3 pathways which will convert the glucose into energy these pathways are called glycolysis, the Krebs cycle, and electron transport. I would like to focus on the two common pathways; glycolysis and the Krebs cycle.
Glycolysis is a series of reactions that convert glucose into pyruvate and help with the production of ATP. This process is anaerobic, which means that oxygen is not present, nor is it needed. The reactions happen within 3 phases and a total of 10 steps. The first phase of glycolysis is sugar activation. This is where the glucose is converted into 2 pyruvic acid molecules. Also, the first 3 steps happen here. Within the first 3 steps, energy is invested to be recouped at a later time. The second phase is called sugar cleavage. During this phase steps 4 and 5 take place. This is where glucose is split into 2 smaller molecules so that energy can be used more efficiently. The last of the 10 steps occur in the final phase called sugar oxidation and ATP formation. During this phase, energy is released as ATP and NADH step by step.
The process of glycolysis can also serve as a source of raw materials for the synthesis of other compounds, such as pyruvic