What is glucose and where does it come from?

What does the body use glucose for?

Glucose is an active monosaccharide sugar obtained in the body as a supplement or as a result of digesting carbohydrates or sugars (disaccharides and polysaccharides), the percentage of blood glucose is regulated by insulin, a pancreatic hormone essential for the metabolism of carbohydrates and lipids, by facilitating the uptake of glucose into tissue and promoting its conversion into glycogen, fatty acids and triglycerides. It is considered the 1st and fastest source for energy. If the amount of glucose consumed is too high it is transformed into glycogen and is stored in adipose tissue.

What elements are found in glucose?

In one single glucose molecule (C6H12O6), there are six carbon atoms, twelve hydrogen atoms, and six oxygen atoms

How do we get energy from glucose?

In the small intestines, glucose is formed by the breakdown of carbohydrates. Glucose is then absorbed into the bloodstream through the villi by active transport. Once in the bloodstream, glucose and oxygen are taken up into cells during aerobic metabolism. During cellular respiration the mitochondria uses the oxygen to burn the glucose into heat energy and adenosine triphosphate (ATP), which is then used to store or release the energy depending on the cell’s needs.

Where is glucose released from and what is glycogen used for?

When blood sugar is low, the islet cells within the pancreas release glucagon, a hormone, This stimulates hepatic cells to turn glycogen back into glucose (glycogenolysis) which can then be released into the blood and the blood sugar levels will then rise. Alternatively, In the fasted state, the liver forms glucose from noncarbohydrates (gluconeogenesis, GNG).

What is gluconeogenesis?

Gluconeogenesis is a metabolic pathway used to maintain blood glucose levels in which glucose is formed from breakdown of glucogenic amino acids, from breakdown of triglycerides and glycerol.

When blood sugar is high, the pancreas releases insulin, a hormone, this stimulates glycolysis and lipogenesis.

What is glycogen and where is glucose stored in the body?

When the cells have sufficient supplies of ATP, the liver cells will try to convert a variety of excess molecules into glycogen in a process called Glycogenesis.

Excess glucose is converted into glycogen, a polysaccharide of glucose, in response to insulin, in the liver. Glycogen is mainly stored in the liver and the muscles. When blood glucose levels decrease, glycogen is broken down into glucose in response to glucagon, thus it provides the body with a readily available source of energy.

How does glucagon regulate blood sugar levels?

When blood glucose level is low, the pancreas secretes glucagon that acts opposite to insulin. Glucagon brings the blood glucose level closer to normal by breaking down glycogen into glucose in the liver. Released glucose enters the blood to be consumed for energy. Additionally, glucagon raises the concentration of fat in the bloodstream by breaking down stored fat from adipose tissue, stored triglycerides are broken down into glycerol and fatty acids in a process called lipolysis. Released fatty acids and glycerol are then delivered to organs and tissues in the body.

Verified by: Dr.Diab (March 10, 2018)

Citation: Dr.Diab. (March 10, 2018). What is glucose and what does the body use glucose for?. Medcoi Journal of Medicine, 5(2). urn:medcoi:article20281.