I'm also at CSN, and I start on the 22nd. Listen, I don't want to scare you, but I've heard that BIO 189 is used as a filter to fail ppl out of programs. It is the hardest class to even get into at CSN due to it being a Pre req for so many majors-I couldn't get in this semester. My advice is to study and follow your instructors syllabus to a "T!"
Now my buddies could have been exaggerating on the difficulty (well not so much difficult as very strict, especially with labs), but I've heard others say this as well. On the bright side though, I also hear that after 189 is done, 223,224 and 251 are a breeze. Always a silver lining, right?
Seriously, good luck with the program