Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to complex carbohydrate: Simple carbohydrate
a polysaccharide, such as a carbohydrate, that is composed of a large number of glucose molecules, so called to distinguish it from a simple sugar.
complex carbohydrateA carbohydrate characterised by chemical complexity and multiple-side chains of glycogen and fibre; complex-carbohydrate-rich foods include whole grains, brown bread, brown rice, vegetables and beans.
1. A starch.
2. A molecule made of several linked saccharides; a polysaccharide.
|Monosaccharides||C6H12O6||Glucose||Crystalline, sweet, very soluble, readily absorbed|
|Pentoses||C5H10O5 or C5H10O4||Ribose||Part of nucleic acid, RNA|
|Deoxyribose||Part of nucleic acid, DNA|
|Disaccharides||(C6H10O5)2·H2O or C12H22O11 hydrolyzed to simple sugars||Sucrose Lactose Maltose||Crystalline, sweet, soluble, digestible Present in milk|
|Polysaccharides||(C6H10O5)n composed of many molecules of simple sugars. (Since polysaccharides can be composed of various numbers of monosaccharides and disaccharides, n refers to an unknown number of these groups.)||Starch Dextrin Cellulose Glycogen||Amorphous, little or no flavor, less soluble. Vary in solubility and digestibility.|
|Enzyme||Produced in||Carbohydrates Digested||End Product|
|Sucrase (invertase)||Small intestine||Sucrose||Glucose and fructose|
|Maltases||Small intestine and mucosal cells of small intestine||Maltose||Two d-glucose|
|Lactase||Small intestine||Lactose||d-glucose and d-galactose|
|Salivary amylase||Saliva (mouth)||Cooked starch, glycogen, and dextrins||Maltose|
|Pancreatic amylase||Pancreas||Raw and cooked starch and glycogen||Maltose|
See also: carbohydrate
a compound of carbon, hydrogen and oxygen, the latter two usually in the proportions of water (CH2O)n. They are classified into mono-, di-, tri-, poly- and heterosaccharides. Carbohydrates in food are an important and immediate source of energy for the body; 1 gram of carbohydrate yields 3.75 calories (16 kilojoules). They are present, at least in small quantities, in most foods, but the chief sources are the sugars and starches of plants. Herbivores are able to utilize the insoluble polysaccharides (crude fiber) because of bacterial conversion to volatile fatty acids by fermentation in the rumen and cecum.
Carbohydrates may be stored in the body as glycogen for future use. If they are eaten in excessive amounts they are converted to and stored as fat. Rapid ingestion of very large amounts in ruminants and horses causes carbohydrate engorgement.
polysaccharides containing either α- and β-type glycosidic bonds. Usually occurring in mixtures in food.
the carbohydrate components of food.
depletion/repletion means of maximally loading glycogen into type II muscle for increased power of muscle contraction.
glucose loss in urine due to diabetes mellitus or chronic renal disease.
series of related enzymic reactions involved in the synthesis and catabolism of carbohydrates.
carbohydrate tolerance test
see glucose tolerance test.