The Physiology of Glucose Metabolism
Glucose is the body's main source of calories. The carbohydrates we eat become glucose when broken down during digestion. Then the glucose is metabolized for use as fuel by the cells. Following are the steps for glucose metabolism simplified.
Food is digested
An increase in blood glucose occurs when food is consumed, especially so with carbohydrates, a main source of calories in a daily diet.
Insulin is created
The pancreas then produces the hormone insulin to break down, transport and metabolize the glucose molecules.
Transportation
The glucose is delivered into the cells through a membrane for use as fuel. Any cell that needs glucose will have a receptor on the surface, inviting the hormone and creating a chemical bond that allows for absorption.
Fuel processing
The glucose then burns to produce heat and ATP (adenosine triphosyphate) creating energy. This may be used right away or stored for later use as fat. If too many carbohydrates are consumed on a regular basis, the system becomes overloaded and a situation of extraneous fat storage is created.
Conversion types
The largest conversion of glucose to ATP happens in the large muscles in the presence of oxygen, called aerobic metabolism; it is a very efficient method. When oxygen runs out in the muscles, but they are still in need of energy, a back up method of glucose metabolism ensues--anaerobic metabolism. Unfortunately the byproduct of this modality is lactic acid, which can build up in the muscles causing soreness.
Tags: glucose metabolism, main source, main source calories, Physiology Glucose, Physiology Glucose Metabolism, source calories