The Anatomy and Physiology of Lipids
When you get up each morning and look outside your window looking out at the beautiful
plants and adorable little animals, have you ever wondered what makes all living things? Lipids are
what help create all the living things we see everyday. Lipids are found in all membranes, mainly
plasma membranes, meaning animals and plants contain lipids. In this paper I will display and
explain the formation of micelles and bi-layers from lipid amphiphilicity. A variety of books were
used to study different types of lipids; the three major components, glycerophospholipids,
sphingolipids, and sterols, and their affects in the cellular and multicultural systems.
Lipids are structural components found in living cells that are either soluble in organic
solvents or insoluble in water.1 These lipid membranes are demonstrated in Singer and Nicolson’s
1972 fluid mosaic model. Lipids are commonly recognized as fats, oils, wax, etc. There are three
major different types of lipids that exist: glycerophospholipids, sphingolipids, and sterols.2
Within each type there are a variety of subtypes.
Glycerophospholipids are commonly referred to as plain phospholipids. Within itself it
contains three components. First it is constructed with a phosphorylated head group, then a three
carbon glycerol backbone, and finally a two hydrocarbon fatty acid chains. The phosphorylated
head group is attached to one of the glycerol hydroxyls with addition to the two hydrocarbon fatty
acid chains bonded to the other two glycerol hydroxyls.3 The purpose for glycerophospholipids is
to construct and or maintain the cell membrane. In a microscopic view of the cell membrane we can
observe that the glycerophospholipids are lined in row making the two layers of the membrane.
The overall responsibility for this structure is to create a fatty barrier from the interior membrane
to the surroundings.
1 David Hames and Nigel Hooper, Biochemistry (New York: Taylor & Francis Group, 2005) 132.
2 Hames and Hooper 132.
Ex. of glycerophospholipid
Structure of phosphatidylinositol
Sphingolipids is another sub-group of lipids that is similar to the glycerophospholipids.
However instead of the glycerol, it is replaced by a sphingosine backbone.4 These lipids are
commonly located within the myelin sheath which is found close to the nerve cells.5 This
component’s responsibility within the neural tissue is to signal transmission and cell recognition.
Signal transmission detects any viral or harmful factors among the surface of the cell and physical
properties and cell recognition is interface with cells that rely on specific adhesion.6 This is very
essential for communication and function throughout living cells.
3 Hames and Hooper 132.
4 Hames and Hooper 133.
5 Hames and Hooper 134.
6 Hames and Hooper 134.