Unadulterated pain. If you are a biology or chemistry student there is a very high probability that this will be the hardest class you take. It is seriously impossible to get an A unless you have a
photographic memory. No, I'm not being snide, I'm being completely serious - learning all the reactions, regulations, pathways, mechanisms, structures, etc. is impossible without it.
Typically offered as an option based around the lie that it will "make your transcript look stronger," the
fact of the matter is that it will drop your GPA like an anchor. Biochemistry has the evil ability to not only make sure you get a low grade in it but that all your other classes grades are brought
down with it. It will also destroy your sleep pattern and social life while drastically increasing your alcohol intake.
Seriously, avoid this like the plague.