exam 3 Flashcards
what removes dried oil from the lens the best?
xylene
numerical aperture
solid cone of light delivered to the specimen by the condenser and gathered by the objective
resolution
ability of scope to reveal fine detail
working distance
the distance from the center of the objective to the top of the specimen “focal length”
aberration
imperfect refraction or focalization of a lens (inability to bring light rays to a single focus)
mirror
reflects the beam of light upward
condenser
directs and focuses the light from the light source up to the specimen
aperture iris diaphragm
controls the amount of light
how do you calculate total magnification of a specimen on a microscope
ocular * objective
what are the three most common objectives used in a clinical lab and what are they otherwise known as
10x- low power
40x- high dry
100x- oil immersion
what magnification are most oculars?
10x
bright field
daylight/ light bulb with compound lens system
darkfield
special condenser makes background dark while specimen is light (light waves cross specimen instead of through it)
fluorescent
equipped with UV light source and special filter to allow shorter wave lengths
phase contrast
uses special diaphragm into or below condenser to view obtained structures
polarized
uses special filter that takes ordinary lightwaves and allows only light waves of only one orientation ( N & S ) to reach specimen illuminating objects that can rotate light
electron
substitution of an electron beam for light rays to achieve greater resolution
field of view
visible area through in focus lens
MSDS
material safety data sheet- provides information on all chemicals used in the laboratory and the potential hazards
diamond hazard symbols
yellow diamond- reactivity
red diamond- fire hazard
blue diamond health hazard
standard precautions
treat all specimens as infectious
class A bioterrorism agents
anthrax botulism plague smallpox tularemia aloviruses (Ebola & Marburg) arenavirusess (lasso, machupo)
Class B Bioterrorism Agents
brucellosis shigella ricin toxin Venezuelan equine encephalitis
Class C Bioterrorism Agents
emerging pathogens (niphha virus, hanta virus)
what is the single most effective way to reduce possibility of contaminating yourself
hand washing
how long is HBV stable in blood products at 25C
7 days
where should contaminated materials be disposed
biohazard waste disposal
explain what an employee should do if they were to get caustic chemicals on their skin or eyes?
skin should be washed for 5 minutes immediately after exposure. If splashed in the eyes wash eyes at eye station with water for 15 minutes and seek medical attention
name 5 safety features all clinical labs should have
fire blankets eye wash first aid kit ppe shower station
T.C.
to contain
contents of pipette should be rinsed out with solution is being added too
T.D.
to deliver
designed to deliver a set volume contents of poppets should be blown out
glassware that resists normal cleaning should be cleaned with what?
potassium or sodium dichromate and concentrated sulfuric acid
name two brand names of heat resistant glassware
pyrex and kimax
volumetric or transfer pipette
calibrated for fixed volume
greatest accuracy and precision
long narrow tube with elongated round bulb near middle
standard/unknown solution
serological pipette
calibrated to tip
blow out pipette
“mark to mark”
not used for exact measurements
Ostwald-folin pipette
specialized version of volumetric
used for whole blood more thick liquids
bulb near tip
graduated or measuring pipette
long straight tube with graduating
“mark to tip”
no accuracy required
what does an etched ring near the mouth of the pipette mean?
means blow out pipette on a serological pipette
erlynmere flasks
flat bottom sides that slope up neck
holding, mixing, and heating noncritical volumes
beakers
various sizes
used for estimating liquids
heat and chemical resistant
graduated cylinders
cylindrical glassware w/ calibration marks
various sizes
measure specific volumes
volumetric or Florence flasks
rounded bottom with long neck
calibrated for specific amount of liquid
volume for noncritical amounts
what is low actinic glassware used for
light sensitive compounds
polyethelyne
most common material used for plastic ware in the lab
primary standard
a reference material that is of fixed and known composition and capable of being prepared in essentially pure form. (99.5% can be retrieved)
secondary standard
a reference material in which the analyte concentration has been ascertained by reference to a primary standard by an acceptable reference method (most common)
A.R.
analytical reagent
has higher degree of purity, used routinely in lab
C.P.
chemically pure
limit of impurities that are tolerated
suitable for general application
N.F.
national formulary
U.S.P.
united states pharmacopeia
less pure than chemically pure but reagents meet specifications (used in medicines)
distilled water
water is boiled, steam forms/ is cooled, vapors collect and condense any minerals remaining
contains dissolved gases and organic solvents
deionized water
most often used
water is passed through a column of charged resin particles
particles combine with ions present to remove them (dissolved gases and organic compounds)
double distilled water
distilled water that has been redistilled to higher degree of proper/ammonia free
reagent grade water
prepared by reverse osmosis most idea used in place of deionized or distilled water to improve control no preservatives
what is the proper storage of chemicals and reagents?
proper temperate
storing powders in a cool, dry place
flammable items stored in flame cabinets away from heat source
properly labeled
five things a reagent label most contain
name and concentration of reagent initials of prepper expiration date use receive date/when purchased/prepared from manufacturer/ date reconstituted/opened
what is the expiration date of a reagent if it is not specified
1 month from opening if not specified
what steps must you take once you have transferred a chemical from the weigh boat into a receiving vessel to ensure an accurately prepared solution?
volumetric flask must be of the correct size and correct balance used funnel and weigh boat used must be rinsed 2-3 times with solvent
rinse weigh boat and funnel with solvents
fixed angle rotor centrifuge
centrifuge cups are positioned rigidly at a fixed angle around the shaft copes enclosed by a metal case.
7000 rpm
horizontal rotor centrifuge
cups in a vertical position when not in use and horizontal position cups 3000 rpm particles being spun must travel the entire length of liquid column to reach the tube bottom
ultracentrifuge
100,000 rpm can be either of fixed or horizontal
may require several hours/days to finish
receptor assays, protein fractionation, drug binding assays, and in clarification of lipemic sera
microhematocrit centrifuge
used most often in hematology to centrifuge small amounts of blood to determine hematocrit
refrigerated blood bank centrifuge
table or floor model that is refrigerated and can spin large amounts of blood
serofuge
small centrifuge at a constant speed (low/high) used for spinning serum cell mixture before reading result
cell washers
used in blood bank to wash RBC’S and centrifuge tubes as mentioned with serofuge
cytospin centrifuge
makes slides in a monolayer usually used in hematology or where body fluid analyses take place
list precautions that should be taken when operating a centrifuge
make sure tubes are balanced
make sure tubes in use can withstand force exerted
if breakage occurs make to extract all blood and glass
centrifuge lid should be closed until fully stopped
trip balance accuracy
nearest 0.1g
analytical balance accuracy
0.1 mg or less
proper placement of an analytical balance
vibration free area of the lab
level work area
away from heat
glass enclosure (analytical balance)
prevents dust from collecting and prevents air currents from interfering
balancing screws (analytical balance)
balance must be properly leveled and these screws are used to adjust the balance until level indicator is centered
