MICRB 107 Lecture Notes - Lecture 3: Nucleoid, Ribosome, Osmosis
Document Summary
Look at figures 4. 2,4. 3,4. 4 for bacteria shapes and arrangements. Eukaryotes grow by binary fissure: cell elongates and dna is replicated, cell wall and plasma membrane begin to grow inward, cross wall forms completely around divided dna, cells separate. Flagella: 12-30nm (cannot see with a gram stain and brightfield microscope: not all bacteria have flagella, rotation gives it motility, chemotaxis: movement to or away from a chemical, phototaxis: movement toward or away from the light. Axial filaments: are underneath a sheath, can not get loose into the environment, the wiggle or rotate through its environment. Fimbriae: straighter, shorter, and thinner then flagella; used for attachment: if the cell loses fimbriae it can"t cause diseae, virulence: capable of causing disease, attach to innate surfaces like rocks and things. Pilus (pili): longer then fimbriae and shorter then flagella: can transfer dna from one cell to another (sexpilus, also involved in motility: twitching or gliding motion.
