<p>I know about the teaching aspect of PhD, but how does difficulty differ from graduate to undergraduate level coursework? I'm interested in medical school but if that falls through I'm just as willing to do research in other biological studies.</p>
<p>PhD study leads to doing original research, pushing out the frontiers of knowledge in the specialty area within the major subject. Course work taken at the beginning of PhD study is more in-depth and specialized, with undergraduate background in the major subject being assumed. Many graduate level courses are seminars where faculty and PhD students discuss their research projects with each other.</p>
<p>ucbalumnus is right - the focus of a PhD is very different from as an undergrad. Courses are secondary to research, in a lot of ways, and you only take courses for less than the first half of a PhD program, usually. The difficulty of the coursework shouldn’t be your main consideration when thinking about a PhD: it’s all about the research. If you don’t have research experience, you won’t get into a PhD program. And once you’re there, your research is what will earn you the PhD.</p>