Microbiology Exam 2 Questions with Answers
1. What is an organism that grows in lower pH conditions
called? Neutrophile
Alkalinophile
Halophile
Barophile
Acidophile:
Acidophile
2. Which term describes a microorganism that obtains nutrients by
decompos-
ing dead organic matter in its
environment? Saprobe
Predator
Parasite
Autotroph
Commensal: Saprobe
3. Organisms that use inorganic carbon
sources (such as carbon dioxide) are known as .
Organisms that use organic carbon sources (such as glucose) are
known as
.: autotrophs, heterotrophs
4. You have discovered a new microorganism while studying out
in the field. After running some tests, you conclude that the
organism uses inorganic carbon from carbon dioxide and acquires
energy from light. Which category does this microorganism fall
under?
Chemoautotroph
Chemoheterotroph
Photoautotroph
Photoheterotroph:
Photoautotroph
5. In what environment would a halophile live?
,Hypotonic
Fresh water
Hypertonic
Isotonic: Hypertonic
6. What is the term for microorganisms that can withstand brief
exposure to elevated temperatures?
Thermophiles
Psychrotolerant
Psychrophiles
Thermoduric
Mesophiles:
Thermoduric
7. Which growth phase requires cells to go through a period of
adjustment,
enlargement, and
synthesis? Death phase
Stationary phase
Exponential growth
phase Lag phase: Lag
phase
8. What type of microorganism obtains energy and carbon by
breaking down
organic
molecules?
Saprobe
Autotroph
Phototroph
Chemoheterotro
ph
Chemolithotroph: Chemoheterotroph
9. During which phase of microbial growth do microorganisms
experience rapid and continuous cell division, doubling the
,population with each generation? Exponential growth phase
Lag phase
Stationary
phase
Death phase: Exponential growth phase
10. In a thioglycolate tube, where would you expect to find
microorganisms that only grow in the absence of oxygen, such as
Clostridium species?
Near the surface, where oxygen is abundant
At the bottom of the tube, where oxygen is completely
depleted In the middle of the tube, where oxygen
concentration is lower
Throughout the entire length of the tube, without a preference for
oxygen levels
, Near the side of the tube, forming a biofilm to protect against
oxygen expo- sure: At the bottom of the tube, where oxygen is completely depleted
11. What is the main difference between a saprobe and a parasite?
A saprobe cannot infect a human, but a parasite is always infectious.
A saprobe derives nutrients from dead plants and animals, but a
parasite derives nutrients from living plants and animals.
A saprobe is a fungus, but a parasite can be any type of microbe.
A saprobe does not harm a host that it lives on, whereas a parasite
does harm a host.: A saprobe derives nutrients from dead plants and animals, but a parasite
derives nutrients from living plants and animals.
12. Microbial life in deep-sea hydrothermal vents relies on
unique nutritional strategies. Which type of microorganism can
synthesize organic compounds from carbon dioxide using the
energy derived from chemical reactions? Chemoautotroph
Chemoheterotroph
Photoheterotroph
Photoautotroph:
Chemoautotroph
13. What term for microbial growth represents the time it takes for
a population
of microorganisms to double in number under optimal growth
conditions? Replication time
Growth rate
Generation time
Exponential time: Generation time
14. Which conditions would be hospitable for a microorganism
that thrives at high pH and temperatures below freezing? Select
all that apply.
Halophile
Alkalinophile
Psychrophile
Neutrophile
1. What is an organism that grows in lower pH conditions
called? Neutrophile
Alkalinophile
Halophile
Barophile
Acidophile:
Acidophile
2. Which term describes a microorganism that obtains nutrients by
decompos-
ing dead organic matter in its
environment? Saprobe
Predator
Parasite
Autotroph
Commensal: Saprobe
3. Organisms that use inorganic carbon
sources (such as carbon dioxide) are known as .
Organisms that use organic carbon sources (such as glucose) are
known as
.: autotrophs, heterotrophs
4. You have discovered a new microorganism while studying out
in the field. After running some tests, you conclude that the
organism uses inorganic carbon from carbon dioxide and acquires
energy from light. Which category does this microorganism fall
under?
Chemoautotroph
Chemoheterotroph
Photoautotroph
Photoheterotroph:
Photoautotroph
5. In what environment would a halophile live?
,Hypotonic
Fresh water
Hypertonic
Isotonic: Hypertonic
6. What is the term for microorganisms that can withstand brief
exposure to elevated temperatures?
Thermophiles
Psychrotolerant
Psychrophiles
Thermoduric
Mesophiles:
Thermoduric
7. Which growth phase requires cells to go through a period of
adjustment,
enlargement, and
synthesis? Death phase
Stationary phase
Exponential growth
phase Lag phase: Lag
phase
8. What type of microorganism obtains energy and carbon by
breaking down
organic
molecules?
Saprobe
Autotroph
Phototroph
Chemoheterotro
ph
Chemolithotroph: Chemoheterotroph
9. During which phase of microbial growth do microorganisms
experience rapid and continuous cell division, doubling the
,population with each generation? Exponential growth phase
Lag phase
Stationary
phase
Death phase: Exponential growth phase
10. In a thioglycolate tube, where would you expect to find
microorganisms that only grow in the absence of oxygen, such as
Clostridium species?
Near the surface, where oxygen is abundant
At the bottom of the tube, where oxygen is completely
depleted In the middle of the tube, where oxygen
concentration is lower
Throughout the entire length of the tube, without a preference for
oxygen levels
, Near the side of the tube, forming a biofilm to protect against
oxygen expo- sure: At the bottom of the tube, where oxygen is completely depleted
11. What is the main difference between a saprobe and a parasite?
A saprobe cannot infect a human, but a parasite is always infectious.
A saprobe derives nutrients from dead plants and animals, but a
parasite derives nutrients from living plants and animals.
A saprobe is a fungus, but a parasite can be any type of microbe.
A saprobe does not harm a host that it lives on, whereas a parasite
does harm a host.: A saprobe derives nutrients from dead plants and animals, but a parasite
derives nutrients from living plants and animals.
12. Microbial life in deep-sea hydrothermal vents relies on
unique nutritional strategies. Which type of microorganism can
synthesize organic compounds from carbon dioxide using the
energy derived from chemical reactions? Chemoautotroph
Chemoheterotroph
Photoheterotroph
Photoautotroph:
Chemoautotroph
13. What term for microbial growth represents the time it takes for
a population
of microorganisms to double in number under optimal growth
conditions? Replication time
Growth rate
Generation time
Exponential time: Generation time
14. Which conditions would be hospitable for a microorganism
that thrives at high pH and temperatures below freezing? Select
all that apply.
Halophile
Alkalinophile
Psychrophile
Neutrophile
