GCU Microbiology Lab Midterm (BIO-205) Questions With
Complete Solutions
How is light refraction reduced?
Placing a drop of immersion oil on the slide
Nutrient agar slant (sig.)
used for long term storage
Nutrient broth (sig.)
used for short term storage
Nutrient agar plate (sig.)
used to count colony and isolate pure colonies
Streaking for isolation
Streak plate 1/3 horizontal, 1/3 vertical, 1/3 horizontal,
sterilizing loop b/w each 1/3 (2-3 streaks each direction)
Contamination and aseptic technique
- Aseptic technique is used to prevent contamination
- Sterilizing loop in bunsen burner and flaming the lip of the test
tubes before and after you are taking samples is aseptic tech.
Inoculation and inoculum
Inoculating the loop (flaming and cooling) in the bunsen burner
prevents contamination
Pure culture vs mixed culture
, - A pure culture contains only one single type
-A mixed culture contains two or more different bacteria.
Subculturing (def. and sig)
Transfer of microorganisms from one media to another sterile
medium. This helps obtain a pure culture to identify bacteria.
cooling the inoculum loop
Is important so the agar doesn't melt and the bacteria isn't killed
in the process of sub-culturing.
Antibiotics (def.)
medicine that inhibits growth of or destroys microorganisms.
(only works on bacteria)
Antimicrobial (def.)
agent that kills microorganisms or stops their growth
Bactericidal (def.)
kills bacteria
Bacteriostatic (def.)
inhibits bacteria growth
How can you tell whether the test microorganism is sensitive or
resistant?
If microorganism is sensitive there will be a greater zone of
inhibition
What does the zone of inhibition represent?
degree of sensitivity of bacteria to a drug/antiseptic
Complete Solutions
How is light refraction reduced?
Placing a drop of immersion oil on the slide
Nutrient agar slant (sig.)
used for long term storage
Nutrient broth (sig.)
used for short term storage
Nutrient agar plate (sig.)
used to count colony and isolate pure colonies
Streaking for isolation
Streak plate 1/3 horizontal, 1/3 vertical, 1/3 horizontal,
sterilizing loop b/w each 1/3 (2-3 streaks each direction)
Contamination and aseptic technique
- Aseptic technique is used to prevent contamination
- Sterilizing loop in bunsen burner and flaming the lip of the test
tubes before and after you are taking samples is aseptic tech.
Inoculation and inoculum
Inoculating the loop (flaming and cooling) in the bunsen burner
prevents contamination
Pure culture vs mixed culture
, - A pure culture contains only one single type
-A mixed culture contains two or more different bacteria.
Subculturing (def. and sig)
Transfer of microorganisms from one media to another sterile
medium. This helps obtain a pure culture to identify bacteria.
cooling the inoculum loop
Is important so the agar doesn't melt and the bacteria isn't killed
in the process of sub-culturing.
Antibiotics (def.)
medicine that inhibits growth of or destroys microorganisms.
(only works on bacteria)
Antimicrobial (def.)
agent that kills microorganisms or stops their growth
Bactericidal (def.)
kills bacteria
Bacteriostatic (def.)
inhibits bacteria growth
How can you tell whether the test microorganism is sensitive or
resistant?
If microorganism is sensitive there will be a greater zone of
inhibition
What does the zone of inhibition represent?
degree of sensitivity of bacteria to a drug/antiseptic
