Agonist Or Antagonist? (Efficacy Spectrum) Round Clock

Biologists, biochemists, and chemists will enjoy any of these gifts featuring the efficacy spectrum of an endogenous agonist. Make others do a double-take with a dose of wry geek humour with any of these gifts featuring the following rhetorical question: "Agonist Or Antagonist?" Specifically, an agonist is a chemical that binds to a receptor of a cell and triggers a response by that cell; an antagonist blocks the action of the agonist; and an inverse agonist causes an action opposite to that of the agonist. Educational, scientific fun for anyone who knows their biochemistry!