@viola137 : Yeah no…doesn’t happen for the lectures/regular class sessions. Graduate students are used in intermediate and advanced course discussion sections (you read primary literature and reviews in the field) as necessary, which makes sense because most are required to TA and already do research in that field. Problem solving sessions in general biology are run by undergraduates who did well. All course directors are tenure or lecture track faculty though…
All the other questions depend on the professor, though I would say that Emory biology courses seem much more diverse in style than near peers privates and a lot of other schools where only lecture and then exams and quizzes dominate the syllabus. A lot more instructors employ active learning, p-sets, and other assignments in their courses than in other biology programs at similar size and larger schools (again even those of similar caliber). Even the literature discussion sections are pretty unique (there are also quite a few classes that do not have small group literature discussions but just heavily integrate literature reading and presentations into the “lecture” syllabus). Emory has tried to enhance undergraduate education beyond its stereotypes of being only about lectures, exams, and memorization. I think it is an excellent undergraduate program in retrospect (some places like to claim that such and such department is strong because the place has a healthcare system or a good research apparatus. Low and behold, further investigation reveals that almost all classes are stereotypical old school memorization, lecture style biology courses. Effort simply has not been put forth to reform them on a massive scale).
I encourage you to go here and look at all of the effort put into biology and other STEM curricula at Emory over a long timespan:
A lot of HHMI grant money has gone towards this: http://cse.emory.edu/home/for_students/graduate_students/hhmi/hhmiccurriculum.html