The term used to describe the plasma membrane because of it's oily nature and embedded proteins is the fluid-mosaic model.
The plasma membrane that surrounds each cell has two layers of phospholipids (fat with phosphorous attached).
Each phospholipid molecule has a head that is attracted to water (hydrophilic) and a tail that repels water (hydrophobic) . Both the layers of the plasma membrane have the hydrophilic ends pointing to the outside forming the outer layer of the plasma membrane and the hydrophobic tails pointing inside and forming the inner layer of the plasma membrane.
Proteins and substances such as cholesterol become embedded in the bi-layer of the plasma membrane giving it a mosaic look.
At body temperature the plasma membrane has a liquid consistency like the vegetable oil and proteins and other substances are able to move across the plasma membrane. Due to this reason the plasma membrane is described using the term fluid-mosaic model.
This membrane is called the fluid mosaic model as it is a mixture of phospholipids, cholesterol, proteins and carbohydrates.
The molecules are able to float around slowly (like islands in the sea). Cholesterol molecules are scattered among the phospholipids to allow the membrane to function properly at body temperature.
It is often said to be a fluid mosaic model.
fluid mosaic
Fluid Mosaic
The term that is used is "lipid bilayer".
fluid mosaic
The Cell Membrane
Proteins embedded in the cell membrane.
There are proteins embedded in the membrane also. Some of these proteins exist on the aqueous side (outside) while others are only embedded on the inside. These are called peripheral membrane proteins. Some proteins go span the entire length of the lipid bilayer and are called transmembrane proteins. Peripheral membrane proteins are only temporarily attached and can become free by some types of stresses (i.e. detergents, solvents etc.). Integral membrane proteins are proteins that are permanently attached to the membrane.
There are two types of proteins that are embedded in phospholipid membranes, extrinsic and intrinsic. Extrinsic proteins are only partially embedded in the membrane. They aid the structural stability of the membrane and when in conjunction with glycolipids can be involved in cell recognition. Intrinsic proteins pass all the way through a membrane. Some of them may be channel proteins which act as passages through the membrane for some molecules and ions.
fluid mosaic
The term that is used is "lipid bilayer".
fluid mosaic
fluid mosaic
fluid mosaic
fluid mosaic
fluid mosaic
The Cell Membrane
lipid bilayer with peripheral and integral proteins embedded throughout.
A soap bubble with inclusions.
fluid mosaic
fluid mosaic