The mole is a unit of measurement that denotes an amount of substance (also called chemical amount). The mole is defined as the number of atoms found in exactly 0.012 kilogram (or 12 grams) of carbon-12, where the carbon-12 atoms are unbound, at rest and in their ground state.
Plasma Membrane Definition. Plasma membrane can be defined as a biological membrane or an outer membrane of a cell, which is composed of two layers of phospholipids and embedded with proteins. It is a thin semi permeable membrane layer, which surrounds the cytoplasm and other constituents of the cell.
The plasma membrane (cell membrane) is made of two layers of phospholipids. The plasma membrane has many proteins embedded in it. The plasma membrane regulates the entry and exit of the cell. Many molecules cross the cell membrane by diffusion and osmosis. The fundamental structure of the membrane is phospho lipid bilayer and it forms a stable barrier between two aqueous compartments.