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.
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This is because insulin allows the glucose to be travelled to the cells and liver for respiration
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