Receptor (biochemistry)

In biochemistry, receptors are special structures that can be found in cells.These are made of protein molecules such as glycoproteins. Receptors bind (attach) to specialised molecules. If the receptor has this type of molecule, it is activated, but if it does not it is deactivated. Depending on its state, a change inside the cell may happen.

In short, receptors work like locks and keys. With the key, the lock can be locked or unlocked. If it is unlocked, the door belonging to it can be opened.