THE TROUBLE WITH TRIBBLES
Cyrano Jones cannot pronounce the word Klingon correctly. He constantly says "Klingin" instead of Klingon.
When Koloth is requesting that the tribbles be removed from the room, part of his goatee (on his left side) disappears.
What exactly was Kirk planning to do if the tribbles didn't eat the grain when he checks the bins? It's an overhead door - if he'd gotten it open it would have cascaded down onto him.