microbiology is the study of bacteria, viruses, the immune system, and their roles in human health, the environment and beyond. job prospects for microbiologists with a bachelor's or higher degree continue to be strong. upper-division courses in immunology, bacterial infectious diseases, virology, and microbial genetics couple laboratory courses with lecture courses to provide students with hands-on practical experience. the b.s. microbiology major includes all four of the upper-division lecture and laboratory course pairs.