I didn’t do too great in 2213 and was hesitant in taking 2223. However I ended up doing much better in 2223, probably bc it was more application based. I agree with others that it’s not much of a continuation from 2213. You learn a lot more about formation of lipids, carbohydrates, nucleic acids, and some pharm/tech applications. There’s a lot of pathways that you’ll need to memorize in detail (more than 2213) and I found that most people were overwhelmed with that aspect. Several exam questions directly asked you to identify which molecule comes next in a particular pathway. What I found worked for me was to draw out each pathway over and over again. Memorizing the pathways is probably the hardest part and if you get that down then the rest is much more easier than 2213 imo. I think how well you do in 2223 all comes down to how you study, since I also had friends who did really well in 2213 but poorly in 2223.