Drugs that bind to receptor site and inhibit its natural function are called

antagonists

Drugs that bind to receptor sites and inhibit their natural function are called 1. antagonists.

Antagonists are drugs that block the action of a natural substance, such as a hormone or neurotransmitter. They do this by binding to the receptor site for the natural substance and preventing it from binding. This can lead to a variety of effects, depending on the natural substance that is being blocked.

For example, beta-blockers are antagonists that block the action of adrenaline and noradrenaline. This can be used to treat high blood pressure and heart disease.

Agonists, on the other hand, are drugs that mimic the action of a natural substance. They do this by binding to the receptor site for the natural substance and activating it. This can lead to a variety of effects, depending on the natural substance that is being mimicked.

For example, morphine is an agonist that mimics the action of endorphins. Endorphins are natural pain relievers, so morphine can be used to relieve pain.

Enzymes are proteins that catalyze chemical reactions in the body. They are not drugs, but they can be inhibited by drugs.

Molecular targets are the specific molecules that drugs interact with. They can be receptors, enzymes, or other molecules.