What is aseptic technique? - Answers A series of operations have been developed to limit the risk of
contaminating these materials during manipulations and to protect researchers from the bacteria
they're using.
What degree is tsa kept at? - Answers 45-50 C
How many environments are sterile? - Answers Only a few that are free from living organisms
What is a domain? What are the 3 domains used to characterize all life forms based on DNA
comparisons? - Answers -Highest level of classification
-Eukarya, archaea, bacteria
Who's is more closely related to eukarya? - Answers -archaea
Do you expect all the different microbes, from the environment you sampled, to grow on your plate,
or will some be missing? Justify your answer. - Answers I believe that all of these domains could be
found on my plate bc it was very dusty, meaning it could contain dust mites (eukarya), bacteria, and
archaea
What is the purpose of kohler illumination? - Answers It's purpose is to maximize the resolution, the
detail provided by magnification.
What is resolution? What is the resolving power of the eye? - Answers It's the ability of a viewing
instrument (the eye, a camera, a microscope)
to distinguish adjacent objects as separate rather than as one larger object
-100um
What are the two most important factors that determine resolving power? What allows for better
resolution in relation to wavelength? - Answers -the quality of the lens system and the wavelength of
the source of illumination
-shorter wavelength=greater resolution
What is the purpose of a microscope? - Answers -To maximize the resolution of small objects and
structures, Cell shape and size, Organelle shape and size, and Protein structure
-Microscopes combine magnification with increased resolving power to produce a clear image
What are the different types of microscopes? - Answers Light, brightfield and fluorescent
microscopes
Describe Light microscopes - Answers -also called compound microscopes, constructed of two lenses
in series that focus rays of light to illuminate the object.
-light microscopes resolving power is about 200 nm
-allows the observer to visualize the outlines of bacterial cells and only glimpse at the larger internal
structures in cells of plants and animals.
Describe brightfield microscopes - Answers -most common light microscope
-one that uses visible light to illuminate the specimen
-Quality brightfield instruments are parfocal and parcentric. This means that the specimen remains in
focus and at the center of the viewing field when objective lenses are rotated.
What is the difference between magnification and resolution? - Answers -Magnification: increasing
the size of an image
-Resolution: the ability to distinguish two points with x distance between them, as two separate
points
-"x" is the resolving power
Why is immersion oil used with kohler? - Answers -Some light is lost when it passes from the
specimen on a glass slide through air to the objective lens.This occurs because the refractive index
(ability to bend light) of glass and air differ.
-The air space can be replaced by a drop of immersion oil, which has a higher refractive index, closer
to that of glass. When the objective lens is lowered into the oil, more light istransmitted to the lens.
How do you read a P20,P200, P1000? What should you never do with a micropipette? - Answers -p20
divide by 10 of what you see on dial
-P200 tells the exact amt you see on the dial
-p1000 multiply by 10 of what you see on the dial
-try to pipette more or less than its capacity and never tip it upside down with the liquid inside it.
What is the correct resolution for 10x, 40x, 100x? - Answers -10x is 0.2
-40x is 0.5
-100x is 1.0