MCB 2010L Exam 2
Name the steps in aseptic transfer of liquid (broth) media. - ANS-Flame the loop with
bunsen burner flame
Grab the broth and swirl it
Flame the tube (Grab it with dominant)
Hold the tube at an angle to prevent contamination
Remove loop from broth
Reflame tube replace cap
Make a smear of bacteria on designation
Sterilize loop with flame
Name the steps in aseptic transfer of a plate media. - ANS-Flame the loop with bunsen
burner flame
Swirl the loop with bacteria transfer to plate use lid as shield
Remove loop from plate
Sterilize loop with flame
Name the steps in aseptic transfer of a slant media. - ANS-Flame the loop with bunsen
burner flame
Flame the tube
Start at base of slant and come up
Transfer to designated tube
Flame the tube once again
Flame the loop after transfer
Which medium was most difficult to determine a type of growth? - ANS-The liquid
medium was the most difficult (broth) because the bacteria was on the bottom
Why in this exercise where specific types of exposure chosen? - ANS-To determine the
different pathogens or bacterias that exist and how we can identify them through either
a test tube or a petri plate.
Free living pathogen - ANS-are free-living; they can survive and reproduce in the
environment without the presence of a host species
What is nonpathogenic bacteria? - ANS-A bacteria incapable of causing disease ie.
e.coli
, What is a pathogen? - ANS-A disease causing agent ie. virus
What is an opportunistic pathogen? - ANS-An infectious microorganism that is normally
a commensal or does not harm its host but can cause disease when the host's
resistance is low
What is a reservoir? - ANS-The reservoir of an infectious agent is the habitat in which
the agent normally lives, grows, and multiplies
What is the definition of ubiquity? - ANS-Something that appears everywhere
Bacillus - ANS-Rod shaped bacteria
Coccus - ANS-Spherical
Spirillium - ANS-spiral shaped bacteria
Vibrio - ANS-comma shaped
Spirochete - ANS-spiral shaped bacteria
What is a pure culture? - ANS-population of cells derived from a single cell
Streptococci - ANS-bacteria that form a chain
Staphylococci - ANS-Pus-forming bacteria that grow in clusters like a bunch of grapes.
They cause abscesses, pustules, and boils.
Streptobacilli - ANS-chains of bacilli
What is a CFU? - ANS--colony forming unit
-only between 30 and 300 cfus are considered statistically valid
What is the purpose of streak plate method? - ANS-isolate pure colonies of bacteria
If you did not obtain isolation in your plate, why would that happen? - ANS-If there are
no colonies, you either did not contaminate correctly or the plate was contaminated with
nearby bacteria.
Name the steps in aseptic transfer of liquid (broth) media. - ANS-Flame the loop with
bunsen burner flame
Grab the broth and swirl it
Flame the tube (Grab it with dominant)
Hold the tube at an angle to prevent contamination
Remove loop from broth
Reflame tube replace cap
Make a smear of bacteria on designation
Sterilize loop with flame
Name the steps in aseptic transfer of a plate media. - ANS-Flame the loop with bunsen
burner flame
Swirl the loop with bacteria transfer to plate use lid as shield
Remove loop from plate
Sterilize loop with flame
Name the steps in aseptic transfer of a slant media. - ANS-Flame the loop with bunsen
burner flame
Flame the tube
Start at base of slant and come up
Transfer to designated tube
Flame the tube once again
Flame the loop after transfer
Which medium was most difficult to determine a type of growth? - ANS-The liquid
medium was the most difficult (broth) because the bacteria was on the bottom
Why in this exercise where specific types of exposure chosen? - ANS-To determine the
different pathogens or bacterias that exist and how we can identify them through either
a test tube or a petri plate.
Free living pathogen - ANS-are free-living; they can survive and reproduce in the
environment without the presence of a host species
What is nonpathogenic bacteria? - ANS-A bacteria incapable of causing disease ie.
e.coli
, What is a pathogen? - ANS-A disease causing agent ie. virus
What is an opportunistic pathogen? - ANS-An infectious microorganism that is normally
a commensal or does not harm its host but can cause disease when the host's
resistance is low
What is a reservoir? - ANS-The reservoir of an infectious agent is the habitat in which
the agent normally lives, grows, and multiplies
What is the definition of ubiquity? - ANS-Something that appears everywhere
Bacillus - ANS-Rod shaped bacteria
Coccus - ANS-Spherical
Spirillium - ANS-spiral shaped bacteria
Vibrio - ANS-comma shaped
Spirochete - ANS-spiral shaped bacteria
What is a pure culture? - ANS-population of cells derived from a single cell
Streptococci - ANS-bacteria that form a chain
Staphylococci - ANS-Pus-forming bacteria that grow in clusters like a bunch of grapes.
They cause abscesses, pustules, and boils.
Streptobacilli - ANS-chains of bacilli
What is a CFU? - ANS--colony forming unit
-only between 30 and 300 cfus are considered statistically valid
What is the purpose of streak plate method? - ANS-isolate pure colonies of bacteria
If you did not obtain isolation in your plate, why would that happen? - ANS-If there are
no colonies, you either did not contaminate correctly or the plate was contaminated with
nearby bacteria.
