Likely a sterile medium means an uncontaminated culture (food free of living organisms) that will grow only the new bacteria introduced for analysis. Source(s): http://www.thefreedictionary.com/sterile
Stonepelt was Bluestar's first mentor and a very well-respected senior warrior of ThunderClan. It is revealed in this book that he took her to the Gathering on her second day as an apprentice because she had caught a squirrel very well for a new apprentice, and the squirrel had been as big as she was.
Characters / Warrior Cats Thunderclan Leaders And Deputies. Only some leaders and medicine cats are remembered by the Clans. Their names cast long shadows over the forest; their deeds-good or evil-are told and retold by each generation until they pass from history to legend. Over the course of Warrior Cats, ThunderClan has seen a variety of leaders and deputies.