Food chemistry
Comprising 75% of the biological world and 80% of all food intake for human consumption, the most common known human carbohydrate is Sucrose. The simplest version of a carbohydrate is a monosaccharide which contains carbon, hydrogen, and oxygen in a 1:2:1 ratio under a general formula of CHO where n is a minimum of 3. Glucose is an example of a monosaccharide as is fructose. Combine them in the picture shown to the right and you have sucrose, one of the more common sugar products around.
Carbohydrate
The most important carbohydrate is glucose, a simple sugar (monosaccharide) that is metabolized by nearly all known organisms. Glucose and other carbohydrates are part of a wide variety of metabolic pathways across species: plants synthesize carbohydrates from carbon dioxide and water by photosynthesis storing the absorbed energy internally, often in the form of starch or lipids. Plant components are consumed by animals and fungi, and used as fuel for cellular respiration. Oxidation of one gram of carbohydrate yields approximately 9 kJ (4 kcal) of energy, while the oxidation of one gram of lipids yields about 38 kJ (9 kcal). The human body stores between 300 to 500 g of carbohydrates depending on body weight, with the skeletal muscle contributing to a large portion of the storage. Energy obtained from metabolism (e.g., oxidation of glucose) is usually stored temporarily within cells in the form of ATP. Organisms capable of anaerobic and aerobic respiration metabolize glucose and oxygen (aerobic) to release energy, with carbon dioxide and water as byproducts.