Carbohydrates

Carbohydrates
Mainly sugars and starches, together constituting one of the three principal types of nutrients used as energy sources (calories) by the body. Carbohydrates can also be defined chemically as neutral compounds of carbon, hydrogen and oxygen. Carbohydrates come in simple forms such as sugars and in complex forms such as starches and fiber. The body breaks down most sugars and starches into glucose, a simple sugar that the body can use to feed its cells. Complex carbohydrates are derived from plants. Dietary intake of complex carbohydrates can lower blood cholesterol when they are substituted for saturated fat. Carbohydrates are classified into mono, di, tri, poly and heterosaccharides. The smallest carbohydrates are monosaccharides such as glucose whereas polysaccharides such as starch, cellulose and glycogen can be large and even indeterminate in length. The energy produced by carbohydrates is 4 calories per gram. Proteins also provide 4 calories per gram. Fats are high-cal; they provide 9 calories per gram. Etymology: Carbohydrates are called carbohydrates because the carbon, hydrogen and oxygen they contain are usually in the proportion to form water with the general formula Cn(H2O)n.
* * *
Class name for the aldehydic or ketonic derivatives of polyhydric alcohols, the name being derived from the fact that the most common examples of such compounds have formulas that may be written as Cn(H2O)n ( e.g., glucose, C6(H2O)6; sucrose, C12(H2O)11), although they are not true hydrates and the name is, in that sense, a misnomer. The group includes compounds with relatively small molecules, such as the simple sugars (monosaccharides, disaccharides, etc.), as well as macromolecular (polymeric) substances such as starch, glycogen, and cellulose. The c. most typical of the class contain carbon, hydrogen, and oxygen only, but carbohydrate metabolic intermediates in tissues also contain phosphorus. See saccharides.

Medical dictionary. 2011.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • carbohydrates — angliavandeniai statusas T sritis ekologija ir aplinkotyra apibrėžtis Apibrėžtį žr. priede. priedas( ai) MS Word formatas atitikmenys: angl. carbohydrates vok. Kohlenhydrate, n rus. карбогидраты; сахариды; углеводы …   Ekologijos terminų aiškinamasis žodynas

  • carbohydrates — n. pl. [L. carbo comb. form, carbon; Gr. hydor, water] Compounds containing carbon, hydrogen and oxygen in the ratio of 1:2:1; see monosaccharide, disaccharide, polysaccharide …   Dictionary of invertebrate zoology

  • carbohydrates — Very abundant compounds with the general formula Cn(H2O) n. The smallest are monosaccharides like glucose; polysaccharides (eg. starch, cellulose, glycogen) can be large and indeterminate in length …   Dictionary of molecular biology

  • carbohydrates — noun A major class of foods that includes sugars and starches …   Wiktionary

  • CARBOHYDRATES —    a class of substances such as the sugars, starch, &c., consisting of carbon, hydrogen, and oxygen, the latter in the proportion in which they exist in water …   The Nuttall Encyclopaedia

  • carbohydrates — car·bo·hy·drate || ‚kɑːbəʊ haɪdreɪt n. class of organic compounds of carbon hydrogen and oxygen …   English contemporary dictionary

  • CARBOHYDRATES — …   Useful english dictionary

  • reserve carbohydrates — carbohydrates that can be stored in the plant or animal in the form of high molecular weight, hydrolyzable compounds such as starch or glycogen …   Medical dictionary

  • Nuclear magnetic resonance spectroscopy of carbohydrates — Carbohydrate NMR Spectroscopy is the application of nuclear magnetic resonance (NMR) spectroscopy to structural and conformational analysis of carbohydrates. This tool allows the carbohydrate chemist to determine the structure of monosaccharides… …   Wikipedia

  • Comparison of energy, carbohydrates, and alcohol in some common beverages — ▪ Table Comparison of energy, carbohydrates, and alcohol in some common beverages* beverage typical volume (fl oz)** energy (kcal) carbohy drates (g) alcohol (g) beer 12 100 150 3 15 12 club soda 12 0 0 0 cocktails 3.5 120 180 4 8 18 24 colas 12… …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”