Search results
Results from the WOW.Com Content Network
The fluid mosaic model explains various characteristics regarding the structure of functional cell membranes. According to this biological model , there is a lipid bilayer (two molecules thick layer consisting primarily of amphipathic phospholipids) in which protein molecules are embedded.
Building on the fluid mosaic model, a framework called the proteolipid code was proposed in order to explain membrane organization. [8] The proteolipid code relies on the concept of a zone, which is a functional region of membrane that is assembled and stabilized with both protein and lipid dependency.
Hence, the layer is called a phospholipid bilayer, or sometimes a fluid mosaic membrane. Embedded within this membrane is a macromolecular structure called the porosome the universal secretory portal in cells and a variety of protein molecules that act as channels and pumps that move different molecules into and out of the cell. [ 2 ]
This was not the first proposal of a heterogeneous membrane structure. Indeed, as early as 1904 Nathansohn proposed a “mosaic” of water permeable and impermeable regions. [20] But the fluid mosaic model was the first to correctly incorporate fluidity, membrane channels and multiple modes of protein/bilayer coupling into one theory.
Illustration of a eukaryotic cell membrane Comparison of a eukaryotic vs. a prokaryotic cell membrane. The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extracellular space).
Cross-sectional view of the structures that can be formed by phospholipids in an aqueous solution. A biological membrane, biomembrane or cell membrane is a selectively permeable membrane that separates the interior of a cell from the external environment or creates intracellular compartments by serving as a boundary between one part of the cell and another.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Until 1982, it was widely accepted that phospholipids and membrane proteins were randomly distributed in cell membranes, according to the Singer-Nicolson fluid mosaic model, published in 1972. [6] [18] However, membrane microdomains were postulated in the 1970s using biophysical approaches by Stier & Sackmann [19] and Klausner & Karnovsky. [20]