The syllabi for F.Y.B.Sc. Microbiology have been revised and modified so as to widen the scope of the subject to be compatible to present developments and needs of the subject. Our effort is to provide the students with the best guidelines in order to help them to achieve the expected outcomes in these changed circumstances. This book covers the entire new and revised syllabus for the first semester of F.Y.B.Sc. (Microbiology) as prescribed by SPPU.