| A | B |
|---|
| Age of Earth | 4.5 billion years ago |
| Earth cooled | ~4 billion years ago |
| Oldest microbial fossil | ~3.5 billion years ago |
| Prokaryotes | no membrane bound organelles, nucleoid has DNA |
| Eukaryotes | membrane bound, nucleus |
| Microbial cells in human | 10^14 |
| 3 lineages of life on earth | Bacteria, Archaea, Eucarya |
| 2 Super domains | prokaryote, eukaryote |
| What does prokaryote encompass? | Bacteria and Archaea |
| Prokaryote Habitat | -10 cels to 120 cels and pH from 1 to 10 |
| Algae | Single and multicellular, pigments for photosynthesis, aquatic, flagella |
| Protozoa | single cellular, 2 to 20 um, autotroph and heterotroph, terrestrial and aquatic, CaCO3 or silica cytoskeletons, some are motile |
| Fungi | single/multicellular, chitin cell wall,, saprophytic (live off decaying material), mostly terrestrial EX- mushrooms, mold, yeast |
| Van Leeuwenhoek | invented 1st microscope able to see microbes |
| 2 basic methods of microbio | Microscopy and pure culture technique (necessary for future advancements) |
| Robert Koch | germ theory |
| John Tyndall | discovered heat-resistant microbes |
| Pasteur | disproved spontaneous generation |
| Enrichment culture | allows isolation of microbes present in low #'s |
| resolution | ablity to distinguish b/t two closely spaced objects |
| Positive stain | cells are stained, but not background |
| Negative stain | cells unstained, background stained |
| simple stain | only one dye used |
| differential stains (definition) | 2+ dyes used to divide bacteria into 2 groups |
| Examples of differential stains | Gram stain (most widely used), endospore stain, capsule stain, acid-fast stain |
| Gram stain | based on chemical differences of the cell wall, stains either purple or red, many types |
| Brightfield Microscopy | for observing stained cells |
| Darkfield Microscopy | for resolving tinyyy objects |
| Phase contrast microscopy | used for observing microbial cells |
| Fluorescence microscopy | can locate specific molecules within cells |
| Light Microscope | mycoplasmas, bacteria, red blood cells, epithelial cells |
| Electron Microscope | all light microscope + viruses, proteins, amino acids and some atoms |
| Scanning Tunneling microscope | atoms, amino acids and proteins |
| Scanning electron Microscope | shows surfaces with great depth of field |
| inoculum | material containing microbes to be placed on solid media/liquid media |
| rich media | mixture of many different organic compounds |
| minimal media | mineral salts of major bioelements, supplemented with a carbon/energy source when necessary |
| sterilizing glassware | dry heat about 180 cels. for several hours |
| most common method of sterilization | autoclave |
| autoclave | maintains pressure at 15 lb/in^2 |
| sterilization of plasticware | gamma ray irradiation or ethylene oxide gas |
| obligate aerobes | require oxygen to grow |
| obligate anerobes | oxygen is toxic |
| facultative anaerobes | can grow with or without oxygen, but if oxygen is present they will use it to grow |
| aerotolerant anaerobes | can grow with of without oxygen, but will not use oxygen to grow |
| Microaerophiles | require 2-10% oxygen to grow |
| BSL 1 | nonpathogenis microbes |
| BSL 2 | pathogens that dont readily transmit by aerosol |
| BSL 3 | pathogens that transmit readily by the aerosol route and pose a serious health threat |
| BSL 4 | pathogens that readily transmit by aerosol and cause fatal diseases that have no cure |
