Lipid

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A lipid is a type of molecule useful in biology. It is also oily or waxy. Fats are made from lipid molecules. Sources of lipid can be found in algae, seeds, meat, cheese, butter and fish. Lipids are long chains of carbon and hydrogen molecules. Lipids are classified as simple and complex. Examples of complex molecules could be steroids or phospholipids.

A very important biological function of lipids is as lipid bilayers, the basis of many cell membranes. Another function of lipids is to serve as an energy reserve.

Structures of some common lipids. At the top are oleic acid and cholesterol.[1][2] The middle structure is a triglyceride composed of oleoyl, stearoyl, and palmitoyl chains attached to a glycerol backbone. At the bottom is the common phospholipid, phosphatidylcholine.[1]

Lipids are a group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), glycerides, phospholipids, and others. The main biological functions of lipids include storing energy, signalling, and acting as components of cell membranes.[3]

References[change | edit source]

  1. 1.0 1.1 Stryer L. Berg J.M. Tymoczko J.L. (2007). Biochemistry (6th ed.). San Francisco: W.H. Freeman, p328/330. ISBN 0-7167-8724-5.
  2. Maitland, Jr Jones (1998). Organic Chemistry. Norton, p139. ISBN 0-393-97378-6.
  3. Fahy E. et al (2009). "Update of the LIPID MAPS comprehensive classification system for lipids". Journal of Lipid Research 50 (Supplement): S9–S14. doi:10.1194/jlr.R800095-JLR200. PMC 2674711. PMID 19098281.