This is highly dependent on the course, do you have a syllabus?
I used to teach 1st year Biochemists organic chemistry, but the organic course for 1st year biochem was exactly the same as it was for chem, so we had to cover a lot of stuff. I suppose the core topics will be the most important:
Acids & Bases
Stereochemistry
Carbonyl Chemistry
Nucleophilic substitution
Elimination
Alkene reactivity