Look over your acid/bases, titration curves, henderson-hasselbach equations, buffers, figure out if your professor requires you to memorize amino acids (if so then do it), look over your aldehyde/ketone/carboxylic acid mechanisms from orgo, you would be better suited to ask people who took the class with the professor you are planning on taking it with because the scope of the course varies greatly from professor to professor.
EDIT
Main things
1. Acid/Bases (titration curves, reactions, etc)
2. Buffers (Henderson-Hasselbach, etc)
3. Amino Acids (Structures, Properties [polarity, acidity, etc])
4. Basic orgo mechanisms (aldehyde,ketone, carboxylic acid, alcohols, etc)
5. Basic types of enzymes (oxidoreductases, transferases, hydrolases, lyase, ligase, isomerases)
6. Structures of the basic monosacchrides (glucose, fructose, ribose, mannose, galactose, etc)
7. Structures of the basic disacchrides (lactose, maltose, cellobiose, sucrose, etc)
8. Starches (amylose, amylopectin), Glycogen/Glycogenin
9. Basic fatty acids (palmitic, stearic, palmitoleic, oleic, linoleic, a-linolenic, etc)
10. Phosphoglycerices, TAGs(triacylglycerides), sphingomyelin, ceramides, etc
This list varies greatly depending on weather you are in a majors course or a non-majors course, one semester, or two semester, etc.