MicroBio Lab Final Review TXST exam with 100% correct solutions 2024

What type of media would you use to allow growth of many bacterial species from the sampled environment? correct answers TSA Where would you incubate a soil sample? correct answers Soil → Room temperature Mouth/touch plate? correct answers Mouth → 37℃ Sample from frozen tundra? Why? correct answers Tundra → at or below 0℃.Why?temperature closest to their natural environment, gives optimal growth Proper sterilization of the inoculating loop before and after use correct answers Always flame heat the loop/spreader, mouth of tubes, and keep close enough to the flame to avoid outside contamination Transferring cultures from liquid-to-plate or liquid-to-liquid? correct answers Will have to use lawn technique with the spreader. Heat → alcohol → heat → let cool next to flame → touch side of the plate before bacteria → spread across plate. Resolution correct answers The ability to distinguish two small objects from each other Magnification correct answers Ability of a lens to make smaller objects seem larger → How to get magnification: Objective lens x eyepiece (eyepiece is always 10!) Parfocal correct answers Ability of the objective lens to stay focused even when the objective lens is changed Proper handling and use of a microscope correct answers Always wipe off oil, carry by base (not just by arm), wrap cord neatly and store, LOWEST OBJECTIVE SHOULD ALWAYS POINT DOWN (4X) Simple stain purpose? correct answers Makes otherwise transparent organisms visible under a microscope . Basic, positively charged stain... correct answers → binds to electronegative surface of a bacteria Basic stains correct answers crystal violet, methylene blue, safranin - Smear preparation from broth and plate culture correct answers Plate culture → need to have a drop of DI water first → thin spread= better visibility