When a drug binds to a receptor in the body , the receptor is activated or inactivated.
Molecules such as hormones, drugs or neurotransmitters that bind to a receptor are called ligands. The binding can be specific and reversible. A ligand may activate or inactivate the receptor; activation may increase or decrease a particular cell function. Each ligand may interact with multiple receptor subtypes.
I'll leave this here:
https://legacy.etap.org/demo/biology_files/lesson6/instruction4tutor.html
A base substitution of G:C to A:T after two rounds of replication.
