A receptor is a molecule located on the outside of a (nerve) cell. Specific substances such as neurotransmitters, hormones or other proteins can bind to this receptor, thereby triggering the cell to do something. For example, the cell may divide, the cell wall may open to allow certain substances to enter the cell, or an action potential may be initiated. Receptors are therefore an important part of the communication of nerve cells.
Author: Job van den Hurk (translated by Pauline van Gils)