MCB 3020 Lecture Notes - Lecture 7: Motility, Non-Cellular Life, Protozoa
Document Summary
Chapter 1: the evolution of microorganisms and microbiology. Types of microbial cells: prokaryotic cells lack a true membrane-delimited nucleus this is not absolute, eukaryotic cells have a membrane-enclosed nucleus, are more complex morphologically, and are usually larger than prokaryotic cells. Classification schemes: three domain system, based on a comparison of ribosomal rna genes, divides microorganisms into. Domain bacteria: usually single-celled, majority have cell wall with peptidoglycan, most lack a membrane-bound nucleus, ubiquitous and some live in extreme environments, cyanobacteria produce significant amounts of oxygen. Domain archaea istinguished from bacteria by unique rrna gene sequences: lack peptidoglycan in cell walls, have unique membrane lipids, some have unusual metabolic characteristics, many live in extreme environments. Domain eukarya- eukaryotic: protists generally larger than bacteria and archaea. Protozoa (cid:373)ay be (cid:373)otile, (cid:862)hu(cid:374)ters, grazers(cid:863) Slime molds two life cycle stages. Water molds devastating disease in plants: fungi. Smallest of all microbes requires host cell to replicate.
