الفهرس 
Glucose MetabolismOnly 14 pages are availabe for public view
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Abstract
Carbohydrates present in diet are in the form of mono-saccharides (glucose, galactose and fructose), disaccharides (maltose, lactose and sucrose) or polysaccharides (starch and cellulose). In the mouth, part of the starch is converted to maltose by salivary amylase. In the small intestine, the pancreatic amylase converts the rest of the starch into maltose and isomaltose, then by intestinal disaccharidases, maltose and other disaccharides are converted to glucose, galactose and fructose which are the end products of carbohydrates digestion.Absorption of carbohydrates take place by Simple diffusion,Facilitated transport,Co-transport (active transport) The way of production of energy from glucose is by oxidation of glucose.The major pathways of glucose oxidation which are mainly for energy production are Glycolysis which is a series of biochemical reactions by which glucose is converted to pyruvate in aerobic condition or converted to lactate in anaerobic condition.Under aerobic conditions one molecule of glucose gives 8 ATP molecules +2 pyruvate molecules which enter citric acid cycle. Under anaerobic condition one molecule of glucose gives 2 ATP molecules+2 lactate molecules. Also amino acids are produced from intermediates of glycolysis, so glycolysis has great importance . The Krebs citric acid or tricarboxylic acid cycles is often called the final common pathway of metabolism. The catabolism of glucose and fatty acids yields acetyl-CoA; metabolism of amino acids yields acetyl-CoA or actual intermediates of the cycle .The citric acid cycle provides a pathway for the oxidation of acetyl-CoA. The reactions occur in the mitochondria of eukaryotes. The pathway includes eight discrete steps. Seven of the enzyme activities are found in the mitochondrial matrix; the eighth (succinate dehydrogenase) is associated with the electron-transport chain within the inner mitochondrial membrane. (Karam, 1997).
Insulin is secreated from islets cells of Langerhans in the pancrease.It is the major hormone controling carbohydrate metabolism ,The major function of insulin is to promote storage of ingested nutrients. (Guyton and Hall, 2004).