I'm taking 251 and 224 in the regular fall semester. I took 223 at unlv in 5 weeks and that was no joke. I couldn't imagine taking other classes with it. In such a short amount of time there's a lot to know. I won't say it's impossible but for me that would've been really difficult. 223 is a difficult course. Don't under estimate it lol. There's a ton is memorization with all the bones and muscles. I would say maybe take anatomy and micro together. I'm pretty sure you can't take both anatomy classes at the same time anyways.