Final answer:
Reversible antagonism can be overcome by increasing the concentration of the agonist or removing the antagonist, while irreversible antagonism results in a long-lasting or permanent loss of receptor function.
Step-by-step explanation:
Reversible antagonism occurs when the effect of an antagonist can be overcome by increasing the concentration of the agonist or by removing the antagonist. In other words, when the antagonist's effects are reversible, the antagonist can be overcome and the desired effect of the agonist can be restored. On the other hand, irreversible antagonism occurs when the antagonist binds irreversibly to the receptor, resulting in a long-lasting or permanent loss of receptor function. In this case, the antagonist's effects cannot be easily reversed by increasing the concentration of the agonist or removing the antagonist.