You're expected to know A&P, and would encourage you to go beyond what structures they show you in school and learn what the structures do, not just where they are and what connects to what.
Others to rattle off:
1) Common sense, it's ABC (you'll learn that acronym quickly), skeletal muscular stabilization and transport. No heroics, that's what PD and Fire do and why we scrape them up.
2) Again, A&P
3) Protocols, protocols, protocols; know them all and know them well. I was in a horrible EMTB program and they were never once brought up. Yours may be similar.
4) Know your "EMT" medications inside and out. Know when to use em, why to use em, what they do (good and bad) and know their dosages. Also, get familiar with common pt medications that you don't carry (ex: learn about coumadin at the very least).
5) You better like documentation, because the more ya write after every call: the safer you and pt will be, the more competent you'll seem and the more billing and supervisors will love you (grammar too!)
6) Know when you're over your head; ask for assistance be it ALS, Police, another ambulance, etc.
Otherwise, hope you can relate to the elderly, show compassion when necessary as well as have a high tolerance for BS. Good luck, you'll do fine!