If the glucose molecule present in the blood is not absorbed then the person will not receive the energy from the glucose and the metabolic products produced by the catabolism and anabolism of the glucose molecule. As the glucose molecule is the basic energy giving molecule, the metabolic balance will collapse. Similarly, the concentration of the insulin molecules must increase after a meal automatically, if this does not happen then the person is prone to diabetes mellitus. (Colwell 2003).
Sugars such as glucose enter the liver from the gut by the hepatic portal vein, the only blood vessel in the body having an extremely variable sugar concentration. Thus it proves that the liver is the important organ as it maintains the blood glucose level. The liver maintains a standard glucose level irrespective of how long or recent the food was taken. When the glucose is in excess the glucose and other hexose sugars such as fructose and galactose are converted into the insoluble glycogen and stored in the liver. When there comes arises a demand for the glucose, the glycogen is converted back into glucose and utilized by the body.
Diabetes is caused because of two reasons. One is due to the lack of insulin and the other is due to the failure of the cell’s receptors to attach the insulin molecules at its receptor sites. The first type is called as type 1 diabetes mellitus and the second type is called as type 2 diabetes mellitus. Sometimes the genetic defects may cause a lack in the secretion of the insulin.