Glucagon is hormone secreted by pancreas. Its main function is just opposite to insulin i.e to increase the blood glucose level by-(i) accelerating the breakdown glycogen into glucose in liver,(ii) by promoting the conversion of other nutrients such as amino acids & lactic acids into glucose in liver & thereby enhances the release of glucose in blood.
Glycogen (C 6 H 10 O 5 ) n is a multibranched polysaccharide made up of glucose subunits. In humans, it is stored in the liver and muscles of the body. It is the chief form of stored energy in the body of animals.
The breakdown of glycogen into glucose – 1 – phosphate is called glycogenolysis.
The generation of glucose from non carbohydrate carbon substrates like pyruvate, lactate etc. is known as gluconeogenesis.
The process of synthesis of glycogen from glucose is known as glycogenesis.