BIOL 2900 Lecture Notes - Lecture 3: Escherichia Coli, Microorganism, Glucosamine
Document Summary
All cellular life has this characteristics in common: Regulates the flow of nutrients and wastes that enter and leave the cell. ) Prokaryotic cell organization and structure: flagellum: long structures that extend beyond surface of cell. Flagella maybe arranged differently depending on species. Function: responsible for movement (rotation propels bacterium through environment. Ii. used in chemotaxis (movement towards or away from substances). Bacteria can sense high and low concentration of various substances and know how to either go towards the high or swim away from the low concentration, this is called chemotaxis. Iii: axial filaments: similar function to flagella. Run lengthwise along cell (look like snakes, family of spirochetes). Fimbria: sticky projections, used by bacteria to adhere to one another, to hosts and to substances in environment. Maybe 100s per cell and are shorter than flagella. Fimbria maybe evenly distributed over entire surface used for attachment. Longer than fimbria but shorter than flagella.