Lab 3.1-3.3- microscopy Flashcards
Father of the microscope:
-Antone Van Leewenhoek
His single lens could only magnify a microbe ??X
-300X
A simple microscope only has ?? lens
-one
What kind of microscope is used in introductory classes and clinical laboratories?
-light microscopy
-specifically a compound light microscopy
Bright field microscopy produces an image made from ?? that is transmitted through a specimen
-light
Ocular lens:
-eyepiece
-magnifies the image formed by the objective lens
Objective lens:-
-primary lenses that magnify the specimen
Stage:
-holds the microscope slide in position
condenser:
-focuses light through the specimen
Diaphragm:
-controls the amount of light entering the condenser
Illuminator:
-light source
Light from the source is focused on the specimen by the ?? lens.
-condenser
It then enter the ?? lens, where it is used to produced a magnified real image.
-objective
Refraction:
-bending of light
The real image is magnified again by ?? lens to produce a virtual image that is seen by the eye.
-ocular
Magnification of each lens in a light compound microscope:
-4X
-10X
-40X
-100X
By focusing the light, the condenser produces a…
-bright field illumination
How should you carry a microscope?
-using both hands
-one hand holding the base and the other holding the arm
What is usually used to gently clean the condenser and objective lens?
-lens paper
To clean an ocular lens, moisten a cotton swab with ?? and gently wipe in a spiral motion.
-cleaning solution
-follow with dry swab
When putting the microscope back in storage what magnifying lens position should it be in?
-4X
What should you do with a plate of bacteria that will NOT be used anymore?
-place it in appropriate receptacle for autoclaving
Autoclaving
-sterilization process that uses pressurized steam to kill infectious agents and denature proteins
T OR F:
controls are not important when conducting an experiment
-False
What should you do if you need to leave the laboratory temporarily in the middle of your work?
-remove your lab coat and gloves
Media, cultures, equipment, and trash in a microbiological lab are sterilized using an —
-autoclave
What is the primary purpose of keeping doors and windows closed during the lab session?
-to reduce the incidence of contamination from microbes traveling in the air
Biosafety level 1:
-organisms do not typically cause disease in healthy individuals
Biosafety level 2:
-organisms are commonly encountered in the community and present moderate hazard only
Biosafety level 3:
-organisms are local or exotic and are associated with respiratory transmission and serious to lethal diseases
Biosafety level 4:
-organisms have a great potential for lethal infection
What protective clothing is recommended in a laboratory setting?
-long pants and closed toe shoes
When should lab bench tops be cleaned with a disinfectant solution?
-at the beginning and end of the lab session
select all features found in light microscope:
-use magnifying lenses with visible light
-resolve structures that are .2 nm apart
-use beam of electrons
-resolve structures that are 200 nm apart
-use magnifying lenses with visible light
-resolve structures that are 200 nm apart
When comparing prokaryotic cells and eukaryotic cells, prokaryotes are —- and —- than eukaryotes.
-smaller and simpler
In order to visualize a virus particle you will need to use a —- microscope.
-electron
The total magnification achieved by the microscope is calculated by — the magnification of the objective and the ocular lens.
-multiplying
TRUE OR FALSE:
The factor that most limits the clarity of the image in a microscope is the magnification.
False
Why is it important to center the object you are analyzing in the field of view of the microscope before switching to a higher power lens?
-as magnification increases, field diameter decreases, and objects at the periphery will no longer be in the visible field.
