The requirements may vary from med school to med school, so the best idea would be to check the MSAR or the school's website. Generally, it is one year of general biology, one year of general chemistry, one year of organic chemistry, and one year of physics and all of their associated labs. Other schools may require a certain number of credit hours of English, math/statistics, and humanities courses also. Biochemistry is usually not required but strongly recommended, and at some schools may be substitued for one semester of organic chemistry.