Microbiology Exam 4
A cell that uses an inorganic carbon source and obtains its energy from
light would be called
a. lithoautotroph
b. photoautotroph
✅
c. chemoautotroph
d. autotroph- b. photoautotroph
Organisms that can grow at pH below 7 are called
a. neutrophiles
b. alkalinphiles
✅
c. acidophiles
d. barophiles - c. acidophiles
Which of the following forms of oxygen is detoxified by the enzyme
catalase?
a. a singlet oxygen
b. hydroxyl radical
✅
c. peroxide anion
d. superoxide radical - c. peroxide anion
A colony of bacteria is an aggregation of cells:
a. arising from single parent cell
b. arising from a cfu
c. arising from the inoculum on the loop
✅
d. at least 200 bacteria
e. both a and b - b. arising from a cfu
Which of the following organisms can cause disease in organisms whose
body temperature is maintained at 37 degrees Celsius?
a. hyperthermophiles
b. mesophiles
✅
c. thermophiles
d. psychrophiles - b. mesophiles
, Barophiles will grow under:
a. high hydrostatic pressure
b. low pH
✅a. high hydrostatic pressure
c. low nitrogen source
d. high carbon dioxide level-
A microbiologist inoculated a growth medium with 200 bacterial cells/ml. If
the generation time of the species is 30 minutes, how many bacterial
cells/ml will there be after 2 hrs of incubation?
a. 8,000
b. 4,000
✅
c. 1,000
d. 3,2000- d. 3,2000
Which of the following is a best method for measuring the number of
microbes when the large volume of sample with very low number of
bacteria?
a. viable plate counts
b. turbidity
✅
c. coulture counter
d. membrane filtration- d. membrane filtration
Obligate anaerobes lack one of the following enzymes that can protect
them from the damaging effects of toxic oxygen.
a. ribozyme
b. superoxide dismutase
✅
c. lipase
d. ligase - b. superoxide dismutase
A(n) ___ organism that is an aerobe but can grow and survive in anaerobic
conditions.
a. obligate anaerobic
b. facultative anaerobic
c. obligate aerobic
A cell that uses an inorganic carbon source and obtains its energy from
light would be called
a. lithoautotroph
b. photoautotroph
✅
c. chemoautotroph
d. autotroph- b. photoautotroph
Organisms that can grow at pH below 7 are called
a. neutrophiles
b. alkalinphiles
✅
c. acidophiles
d. barophiles - c. acidophiles
Which of the following forms of oxygen is detoxified by the enzyme
catalase?
a. a singlet oxygen
b. hydroxyl radical
✅
c. peroxide anion
d. superoxide radical - c. peroxide anion
A colony of bacteria is an aggregation of cells:
a. arising from single parent cell
b. arising from a cfu
c. arising from the inoculum on the loop
✅
d. at least 200 bacteria
e. both a and b - b. arising from a cfu
Which of the following organisms can cause disease in organisms whose
body temperature is maintained at 37 degrees Celsius?
a. hyperthermophiles
b. mesophiles
✅
c. thermophiles
d. psychrophiles - b. mesophiles
, Barophiles will grow under:
a. high hydrostatic pressure
b. low pH
✅a. high hydrostatic pressure
c. low nitrogen source
d. high carbon dioxide level-
A microbiologist inoculated a growth medium with 200 bacterial cells/ml. If
the generation time of the species is 30 minutes, how many bacterial
cells/ml will there be after 2 hrs of incubation?
a. 8,000
b. 4,000
✅
c. 1,000
d. 3,2000- d. 3,2000
Which of the following is a best method for measuring the number of
microbes when the large volume of sample with very low number of
bacteria?
a. viable plate counts
b. turbidity
✅
c. coulture counter
d. membrane filtration- d. membrane filtration
Obligate anaerobes lack one of the following enzymes that can protect
them from the damaging effects of toxic oxygen.
a. ribozyme
b. superoxide dismutase
✅
c. lipase
d. ligase - b. superoxide dismutase
A(n) ___ organism that is an aerobe but can grow and survive in anaerobic
conditions.
a. obligate anaerobic
b. facultative anaerobic
c. obligate aerobic
