level of biosafety - Answers determined by the infectivity, severity of disease, transmissibility,
and nature of work conducted with microbes in the lab
BSL-2 Lab Contents - Answers - personal protective equipment including gloves, lab coat, and
eye protection
- sinks and eye wash stations
- restricted access to the lab for authorized persons only
- autoclaves or alternative methods of decontamination
Required PPE - Answers gloves, lab apron/coat, goggles, close-toed shoes, and long pants/skirt
agar - Answers a mixture of polysaccharide and pectin that is derived from red algae
complex/undefined media - Answers exact ingredient concentrations are unknown
defined media - Answers ingredients are purified and concentrations are precisely known; does
not contain animal or yeast extract
sterilization - Answers a process that eliminates or deactivates all biological agents
parts of an autoclave - Answers - chamber: where items are loaded
- jacket: the area surrounding the chamber
phases of an autoclave cycle - Answers 1. purge phase
2. sterilization phase
3. exhaust phase
purge phase - Answers steam flows into the chamber and replaces air with steam; pressure is
ramped up slowly
sterilization phase - Answers the exhaust valve is closed, causing the temperature and pressure
to reach the desired setpoint; the autoclave program maintains these settings for the desired
time set
exhaust phase - Answers pressure is slowly released from the chamber through an exhaust
valve until ambient pressure is reached
petri dish storage - Answers petri dishes should be stored upside down to prevent condensation
from dripping onto the agar and spreading bacteria
handwashing - Answers microbial numbers are significantly reduced by gently scrubbing living
, tissue with soap to avoid the transmission of pathogenic microbes
aseptic technique - Answers a combination of protocols that collectively maintain sterility to
prevent contamination of a patient or surface with infectious agents
sterile field - Answers a designated area that is kept free of all vegetative microbes, endospores,
and viruses
pipettor - Answers a tool used to transport small amounts of fluid from one location to another
accuracy - Answers the ability to transfer a volume of liquid that is close to the true or nominal
value as indicated by the pipette tool itself
precision - Answers the ability to transfer a volume of liquid in a uniform, repeatable fashion
water density and its use - Answers water has a density of 1 g/mL; this value is used to verify
the accuracy of a pipette by weighing the volume of water dispensed and comparing it to its
density
brightfield microscope - Answers a light and compound microscope that contains lenses that
produce a dark image on a bright background
ocular lenses - Answers magnify images by 10 times
objective lenses - Answers lenses on a rotating nosepiece with magnifications ranging from 4x
to 100x
Total magnification equals... - Answers ocular lens magnification times objective lens
magnification.
specimen - Answers a microbe viewed under a brightfield microscope
stage - Answers a platform that holds a glass slide for viewing
mechanical stage knobs - Answers move the slide on the surface of the stage forward and
backward
coarse focusing knob - Answers used for large-scale movements with only the 4x and 10x
objective lenses
fine focusing knob - Answers used for small-scale movements, especially with 40x or 100x
objective lenses
illuminator - Answers a high-intensity bulb positioned below the stage
condenser lens - Answers above the illuminator; focuses light rays on the specimen to
maximize illumination