checking prereqs for science courses

<p>I was just wondering how strict they are on prereqs for science courses (mainly ib)? I've heard that for labs they usually enforce the prereq requirement but lecture they don't really care. I'm asking because I may not be able to take bio1b until next spring (though I do have ap credit)</p>

<p>They don’t really check it. I know Bio 1AL and Chem 3B does, Upper-division rarely checks.</p>

<p>nice! thanks. would exclusive classes like ib 131 or 132 be different though?</p>