CARBOHYDRATE METABOLISM

Carbohydrates  are  broken down into  monosaccharides which are absorbed into  the  blood stream.  In  the  liver and muscles, most  of  the glucose  is  changed  into  glycogen  by  the  process of  glycogenesis  (anabolism). Glycogen  is  stored  in  the  liver and muscles until  ne'eded  at  some later time when glucose levels are low. If b!?od  glucose levels are low, then epinephrine and glucagon horniones  are  secreted  to  stimulate the  conversion of glycogen  to  glucose. This process  is called glycogenolysis (catabolism).  If glucose is needed immediately upon entering the cells to supply energy, it begins the metabolic process called glycolysis (catabolism). The end products of glycolysis  are pyruvic acid and ATP. Since glycolysis releases  relatively little ATP,  further  reactions  continue  to  convert  pyrlivic  acid  to acetyl CoA and then citric acid  in  the citric acid cycle.  'The majority  of  the ATP  is made from oxidations  in  the citric acid cycle in connection with the electron transport chain.