Microorganisms make life possible, and their study has taken life science into the molecular age. This course is designed primarily for biology majors and will introduce the fundamentals of prokaryotic cell structure and function, metabolism and physiology, taxonomy, microbial genetics and mechanisms of gene transfer inclusive of both bacteria and viruses. Discussions will emphasize the profound importance of microbial symbiosis ranging from key trophic interactions in the biosphere to key influences upon the human microbiome. This course will provide conceptual background sufficient to enable students to engage more advanced coursework in related fields. Either BIOL 304 or BIOL 305 may be used to satisfy elective requirements for the biology major, but no student may take both of these courses. Prerequisite or may be taken concurrently: BIOL 288 and CHEM 211, or permission of the instructor. 3 lecture and on 3-hour lab periods. 4 credits.