<p>So I can lend some insight on this. I’m a senior chem major, but I did bio research and I applied to grad school in bio. </p>
<p>1) What do you consider a “toasted” GPA? Everyone I know who had 3.5+ has done very well in grad school admissions (got into 1st or 2nd choice, with these being places like MIT, Stanford, UNC, Berkeley, etc.) I don’t know how people with 3.0-3.5 fare. With below a 3.0 it’d be very difficult to get into grad school, but I don’t think you would have a problem in the Biology major getting above a 3.0. </p>
<p>2) This is hugely lab dependent. If you work for a particularly famous prof with a large lab, you are unlikely to interact with him/her directly very often. However, if you choose a smaller lab, you will have more direct contact with the PI. (This is the same thing you hear when you apply to grad school, btw). Most labs will have you work with a graduate student or postdoc, at least at first. I don’t think you will find the system very different at any other institution. What I will say is that if you want to do research at Caltech you will have plenty of opportunities to do so. About 80% of our students participate in one way or another. Also I think the quality of our students’ research and the respect other schools have for our faculty definitely shows in graduate school admissions.</p>