Question

There are two types of receptor proteins. Most of them are plasma membrane proteins. Describe the characteristics of the ligands that bind to this type of receptor.

Answer 1

Ligands are the signaling molecules that bind to the receptors present inside the cell or on the cell surface. There are two types of receptors intracellular and cell surface receptors.

Intracellular receptors present in cytoplasm and nucleus and cell surface receptors are embedded in the plasma membrane and responsible for cell signaling, for example, GPCR receptors.

All the hydrophilic ligands or signaling molecules binds to cell surface receptors and some lipophilic ligands also bind to cell surface receptors while ligands that bind to intracellular receptors are lipophilic because they have to cross the cell membrane.