PATHOLOGY

Detailed explanation-1: -Cellular receptors are proteins either inside a cell or on its surface which receive a signal. In normal physiology, this is a chemical signal where a protein-ligand binds a protein receptor. The ligand is a chemical messenger released by one cell to signal either itself or a different cell.

Detailed explanation-2: -A ligand is a molecule that binds another specific molecule, in some cases, delivering a signal in the process. Ligands can thus be thought of as signaling molecules. Ligands interact with proteins in target cells, which are cells that are affected by chemical signals; these proteins are also called receptors.

Detailed explanation-3: -Small, hydrophobic ligands can pass through the plasma membrane and bind to intracellular receptors in the nucleus or cytoplasm. In the human body, some of the most important ligands of this type are the steroid hormones.

Detailed explanation-4: -Within biochemistry, a ligand is defined as any molecule or atom that irreversibly binds to a receiving protein molecule, otherwise known as a receptor.

Detailed explanation-5: -G-protein coupled receptors are usually found in the plasma membrane. The receptor binds a ligand from outside the cell. This binding causes a conformational change in the receptor such that the conformation of the cytoplasmic face of the receptor is altered.