What is Carbohydrate?
{{Use mdy dates|date=May 2020}} [[File:D-Fructose.svg|88px|right|thumb|A diagram of the structure of [[fructose]]]] '''Carbohydrates''' are [[chemical compound]]s that contain ''only'' [[oxygen]], [[hydrogen]] and [[carbon]]. They are made up of joined-up [[sugar]]s. Sugars have the general formula C<sub>m</sub>(H<sub>2</sub>O)<sub>n</sub>, and are also known as '''saccharides.''' Certain carbohydrates are an important storage and transport form of [[energy]] in most [[organism]]s, including [[plant]]s and [[animal]]s. == Biochemistry == There are four types of carbohydrates, named by the number of sugar molecules they contain. # Simple saccharides with one or two sugar molecules ## [[Monosaccharide]]s: single sugar e.g. [[glucose]], [[fructose]]<ref>{{Cite web|title=Monosaccharides - an overview {{!}} ScienceDirect Topics|url=https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/monosaccharides|access-date=2021-06-03|website=www.sciencedirect.com}}</ref> ## [[Disaccharide]]s: two saccharides. e.g. [[sucrose]], [[lactose]], [[maltose]] # Longer chain saccharides: ## [[Oligosaccharide]]s (shortish chains), often linked to [[amino acid]]s or [[lipid]]s. They play a special role in [[cell membrane]]s. ## [[Polysaccharide]]s (long chains) are complex carbohydrates, with linear chains of sugars or branched clusters. Their function is either energy storage ([[starch]], [[glycogen]]) or building structures ([[cellulose]], [[chitin]]). == Nutrition and foods == Carbohydrates are the most common source of energy for the human body. [[Protein]] builds tissue and cells in the body. Carbohydrates are very good for energy, but, if a person eats more than needed, the extra is changed into [[fat]] through a process called [[de novo lipogenesis]].<ref>{{Cite journal|date=2014-07-01|title=De novo lipogenesis in health and disease|url=https://www.sciencedirect.com/science/article/abs/pii/S0026049514001115|journal=Metabolism|language=en|volume=63|issue=7|pages=895–902|doi=10.1016/j.metabol.2014.04.003|issn=00