Carbohydrates are the most abundant organic molecules in nature. The term carbohydrate is derived from the French term hydrate de carbon indicating that it is a hydrate of carbon or CnH2nOn or (CH2O)n. Carbohydrates are often referred to as saccharides. They are broadly classified into three major groups: monosaccharides, oligosaccharides and polysaccharides. This categorization is based on the number of sugar units.
Functions of Carbohydrates
- Carbohydrates are the most abundant dietary source of energy 4Cal/ g for all organisms.
- Carbohydrates are precursors for many organic compounds (fats, amino acids).
- Carbohydrates( as glycoproteins and glycolipids) participate in in the structure of cell membrane and cellular functions such as cell growth adhesion and fertilization.
- They are structural components of many organisms. These include the fibre (cellulose) of plants, exoskeleton of some insects and the cell wall of microorganisms.
- Carbohydrates also serve as the storage form of energy (glycogen) to meet the immediate energy demands of the body.