Yay, it's back! :D
.... Shoot, there weren't any fun unanswered or partially-answered biology questions in this episode to expand on! XD
All I've got is that "bolus" can actually be used to describe any roundish, soft lump of stuff. :B Or, when used to describe medicines, a bolus is a single discrete large-ish dose -- basically administering a clump of whatever drug/compound you're giving in one go in order to raise its concentration in the body to effective levels.