Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download 12.Prokaryotes
Document related concepts
no text concepts found
Transcript
Prokaryotes Prokaryotes Three domains Bacteria – prokaryotes Archaea – prokaryotes Eukarya – eukaryotes Two prokaryotic domains • • • • • Bacteria – typical heterotrophic bacteria, photosynthetic cyanobacteria pathogens Archaeobacteria halophiles hermophiles acidophiles Bacteria • binary fission, type of reproduction • peptidoglycan, cell wall composition • flagella composed of flagellin,• ribosomes, small and free in cytosol • nucleiod for a circular dsDNA • ubiquitous • colony – tens of thousands of organisms all • originating from a single cell that underwent binary fission Bacterial Morphology • Three basic shapes:• coccus,• bacillus • • spirillum • draw the three basic shapes Coccus shape-spherical shape Bacillus-rod shape Spirillum-spiral shape Bacterial Culture and Staining • Bacterial Culture and • Staining • grown in:• broth and agar (Petri plates or slants) • Gram stain – divides bacteria • • Gram positive- thick cell wall- retains crystal violet color • • Gram negative- double walls- retains counterstain safranin color Hans Christian Gram Staining Gram • • • • • • • • • • Collect bacteria with sterile inoculating loop Heat fix slide Stain 1. Crystal violet (primary stain) for 20 sec, rinse with water 2. Iodine (mordant) for 60 sec, rinse with water 3. Ethanol (decolorizer) dropwise, rinse with water 4. Safranin (counterstain) for 20 sec, rinse with water Blot dry with bibulous paper View at 1000x total magnification Biochemical Identification • Compare your plates to the agar slants and petri dishes to identify the bacteria
Related documents