Carbohydrates - organic compounds whose composition often includes three chemical elements: Carbon, Hydrogen and oxygenation.A lot of carbohydrates in addition to these elements contain Phosphorus, Sulfur, and Nitrogen.These biopolymers are widespread in nature.Biosynthesis of carbohydrates in the plants is carried out as a result of photosynthesis.Carbohydrates make up about 80-90% of the dry weight of plants.
In humans, the concentration of carbohydrate based on the dry matter of about 2% percent.Carbohydrates are a major source of chemical energy to the body.Splitting of carbohydrates is of particular importance for the functioning of some organs.For example, individual agencies meet their needs mainly due to the splitting of glucose: the brain - by 80%, heart - 70 - 75%.Carbohydrates are deposited in the tissues of the body in the form of food reserves (glycogen).Some of them perform support functions (hyaluronic acid), are involved in the protective function, delay the development of microbes (mucus) is the chemical basis for the construction of biopolymer molecules, components of energy compounds, etc.
Classification of carbohydrates.
All carbohydrates are divided into two groups: monosaccharides (simple carbohydrates or monosaccharides), polysaccharides (complex carbohydrates or polyose), which consist of a few residues of molecules of monosaccharides linked together.
Classification of carbohydrates: monosaccharides.
monosaccharides containing an aldehyde group, called aldose, and those that contain a ketone group - ketosis.By the simple carbohydrates are aldegido- and keto alcohols with carbon number of not less than three.According to the number of carbon atoms are divided into monosaccharides triose tetroses, pentoses, hexoses, etc.
trioses.Contained in tissues and body fluids in the form of phosphoric acid esters as an intermediate product of carbohydrate metabolism during glycolysis and fermentation reactions.Tetroses.Most importantly erythrose it contained in tissues as an ester of orthophosphoric acid - product of the pentose pathway carbohydrate oxidation.Pentoses.Most pentoses produced in the human digestive tract as a result of hydrolysis of pentosans fruit and vegetables.Part pentoses formed during intermediary metabolism, in particular in the pentose pathway.The pentose tissues are in a free state in the form of acid esters ortofosfatnoi included in the energy compounds (ATP), nucleic acids, co-enzymes (NADPH, FAD), and other important biosoedineny.Particularly noteworthy are pentose sugars: arabinose, ribose, deoxyribose, xylulose.Hexose.There are in the free state in the composition of polysaccharides and other compounds.The most important representatives of this class of carbohydrates are glucose, fructose, galactose, Munoz.
Classification of carbohydrates: disaccharides.
Disaccharides - are carbohydrates whose molecules are cleaved by hydrolysis into two molecules of hexoses.By disaccharides include maltose, sucrose, trehalose, lactose.
When naming disaccharides commonly used names that are historical (lactose, maltose, sucrose), at least - the rational and the nomenclature of IUPAC.
Disaccharides - crystalline solids, readily soluble in water, is optically active, sweet taste liable to acid or enzymatic hydrolysis, may form esters.
Classification of carbohydrates: gomopolisaharidy and heteropolysaccharides.The structure includes a large number gomopolisaharidov one monosaccharide residues: glucose, Munoz, fructose, xylose, etc.They are spare (redundant) nutrients for the body (glycogen, inulin, starch).Heteropolysaccharides molecules consist of a large number of different monosaccharides.
