I can recommend you my favourite topics i had learned from my sophomore year:
- The Cell
- Biomolecules
- Cell Division
- Central Dogma
- Photosynthesis
- Genetics
- Skeletal System
It's not in order but yeah, the easiest i think is the Skeletal System. You just have ego memorise the bones in the body (mandible, maxilla, humerus, radius ...)
Good luck! I hope i helped :)
