The nucleus is separated from the cytoplasm by the nuclear membrane . The cytoplasm , on the other hand, is separated from the surrounding fluids by the cell membrane.
A typical cell 2 types of cell: Prokaryotes are not as structurally complex as eukaryotes, and were thought not to have any compartments enclosed by lipid membranes . In the past they were often viewed as having little internal organization, but slowly details are emerging about prokaryotic internal structures Eukaryotes are the most structurally complex known cell type, and by definition are in part organized by smaller interior compartments, that are themselves enclosed by lipid membranes that resemble the outermost cell membrane .
a thin, pliable, very elastic structure only 7.5 to 10 nm thick.
composed of a lipid bilayer & associated proteins
Envelops the cell
aids in maintaining its structural & functional integrity
recognize other cells & macromolecules
Exhibits a trilaminar structure called The unit membrane
The structure of a cell membrane/plasma membrane.
the structure of a cell membrane It is mainly composed of a lipid bilayer of phospholipid molecules but with a large numbers of protein molecules protruding the layer. LIPID BILAYER is the basic structure of the cell membrane. It is composed entirely of phaopholipid s and cholesterol. Interspersed in this lipid film are large globular protein molecules. Most of the membrane proteins are glycoproteins.
-molecules transported away from the thermodynamic equilibrium
Ex. Sodium-Potassium Pump
- the most important transport mechanism in the body which transport sodium out of cells to the exterior and at the same time pumps potassium ions from the outside to the inside. This is an example of Active Transport Process.
1. Maintain constant cel volume by decreasing the intracellular ion concentration and increasing the extracellular ion concentration, thus decreasaing the flow of water into cell.
2. Maintenance of a potential difference across the plasma membrane