Foundations in Microbiology 6th Edition
by Kathleen Park - Test Bank
Questions 1 – 15 (Chapter 1: The Main Themes of Microbiology)
1. Disease-causing microorganisms are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: C. pathogens.
Rationale: The term "pathogen" specifically refers to any microorganism or agent
capable of causing disease in a host .
2. The microorganisms that recycle nutrients by breaking down dead matter and
wastes are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: A. decomposers.
Rationale: Decomposers are essential for nutrient cycling; they break down dead
,organic matter and waste, releasing inorganic nutrients back into the environment for
use by other organisms .
3. The microorganisms that do not have a nucleus in their cells are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: B. procaryotes.
Rationale: Prokaryotes (bacteria and archaea) are characterized by the absence of a
membrane-bound nucleus and other organelles .
4. When humans manipulate the genes of microorganisms the process is called
A. bioremediation.
B. genetic engineering.
C. epidemiology.
D. immunology.
E. taxonomy.
Answer: B. genetic engineering.
Rationale: Genetic engineering involves the direct manipulation of an organism's genes
using biotechnology. When applied to microbes, this allows humans to produce insulin,
vaccines, and other products .
5. Which of the following is not considered a microorganism?
A. mosquito
B. protozoa
C. bacteria
D. viruses
E. fungi
,Answer: A. mosquito
Rationale: A mosquito is a multicellular insect visible to the naked eye, thus it is not
classified as a microorganism. Microbes include bacteria, viruses, fungi (yeasts/molds),
and protozoa .
6. All microorganisms are best defined as organisms that
A. cause human disease.
B. lack a cell nucleus.
C. are infectious particles.
D. are too small to be seen with the unaided eye.
E. can only be found growing in laboratories.
Answer: D. are too small to be seen with the unaided eye.
Rationale: The defining characteristic of a microorganism is its size (generally less than
0.1 mm), requiring a microscope for visualization. While many lack a nucleus
(prokaryotes), some (eukaryotes like protozoa) do have a nucleus .
7. Which activity is an example of biotechnology?
A. bacteria in the soil secreting an antibiotic to kill competitors
B. a microbiologist using the microscope to study bacteria
C. humans using yeast to make beer and wine
D. Mycobacteria tuberculosis in the lungs causing tuberculosis
E. public health officials monitoring diseases in a community
Answer: C. humans using yeast to make beer and wine.
Rationale: Biotechnology is the use of living organisms (or their parts) to create useful
products. The ancient practice of fermentation (using yeast to produce alcohol) is a
classic example of biotechnology .
8. Which of the following is a unique characteristic of viruses that distinguishes
them from the other major groups of microorganisms?
A. cause human disease
B. lack a nucleus
, C. cannot be seen without a microscope
D. contain genetic material
E. lack cell structure
Answer: E. lack cell structure.
Rationale: Unlike bacteria, fungi, or protozoa, viruses are acellular (not cells). They are
composed solely of genetic material (DNA or RNA) surrounded by a protein coat and
are incapable of independent reproduction .
9. The Dutch merchant who made and used quality magnifying lenses to see and
record microorganisms was
A. Francesco Redi.
B. Antonie van Leeuwenhoek.
C. Louis Pasteur.
D. Joseph Lister.
E. Robert Koch.
Answer: B. Antonie van Leeuwenhoek.
Rationale: Van Leeuwenhoek, a Dutch drapery merchant, perfected simple microscopes
and was the first person to observe and describe bacteria and protozoa, which he called
"animalcules" .
10. Pasteur used swan-neck flasks in his experiments to prove that
A. air had "vital forces" capable of spontaneous generation.
B. microbial fermentation could be used to make wine.
C. dust in air was a source of living microorganisms.
D. microorganisms could cause disease.
E. microorganisms could be grown in laboratory infusions.
Answer: C. dust in air was a source of living microorganisms.
Rationale: Pasteur's swan-neck flask experiment demonstrated that sterilized infusions
remained sterile unless dust (carrying microbes) entered the flask. This disproved
spontaneous generation .
by Kathleen Park - Test Bank
Questions 1 – 15 (Chapter 1: The Main Themes of Microbiology)
1. Disease-causing microorganisms are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: C. pathogens.
Rationale: The term "pathogen" specifically refers to any microorganism or agent
capable of causing disease in a host .
2. The microorganisms that recycle nutrients by breaking down dead matter and
wastes are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: A. decomposers.
Rationale: Decomposers are essential for nutrient cycling; they break down dead
,organic matter and waste, releasing inorganic nutrients back into the environment for
use by other organisms .
3. The microorganisms that do not have a nucleus in their cells are called
A. decomposers.
B. procaryotes.
C. pathogens.
D. eucaryotes.
E. fermenters.
Answer: B. procaryotes.
Rationale: Prokaryotes (bacteria and archaea) are characterized by the absence of a
membrane-bound nucleus and other organelles .
4. When humans manipulate the genes of microorganisms the process is called
A. bioremediation.
B. genetic engineering.
C. epidemiology.
D. immunology.
E. taxonomy.
Answer: B. genetic engineering.
Rationale: Genetic engineering involves the direct manipulation of an organism's genes
using biotechnology. When applied to microbes, this allows humans to produce insulin,
vaccines, and other products .
5. Which of the following is not considered a microorganism?
A. mosquito
B. protozoa
C. bacteria
D. viruses
E. fungi
,Answer: A. mosquito
Rationale: A mosquito is a multicellular insect visible to the naked eye, thus it is not
classified as a microorganism. Microbes include bacteria, viruses, fungi (yeasts/molds),
and protozoa .
6. All microorganisms are best defined as organisms that
A. cause human disease.
B. lack a cell nucleus.
C. are infectious particles.
D. are too small to be seen with the unaided eye.
E. can only be found growing in laboratories.
Answer: D. are too small to be seen with the unaided eye.
Rationale: The defining characteristic of a microorganism is its size (generally less than
0.1 mm), requiring a microscope for visualization. While many lack a nucleus
(prokaryotes), some (eukaryotes like protozoa) do have a nucleus .
7. Which activity is an example of biotechnology?
A. bacteria in the soil secreting an antibiotic to kill competitors
B. a microbiologist using the microscope to study bacteria
C. humans using yeast to make beer and wine
D. Mycobacteria tuberculosis in the lungs causing tuberculosis
E. public health officials monitoring diseases in a community
Answer: C. humans using yeast to make beer and wine.
Rationale: Biotechnology is the use of living organisms (or their parts) to create useful
products. The ancient practice of fermentation (using yeast to produce alcohol) is a
classic example of biotechnology .
8. Which of the following is a unique characteristic of viruses that distinguishes
them from the other major groups of microorganisms?
A. cause human disease
B. lack a nucleus
, C. cannot be seen without a microscope
D. contain genetic material
E. lack cell structure
Answer: E. lack cell structure.
Rationale: Unlike bacteria, fungi, or protozoa, viruses are acellular (not cells). They are
composed solely of genetic material (DNA or RNA) surrounded by a protein coat and
are incapable of independent reproduction .
9. The Dutch merchant who made and used quality magnifying lenses to see and
record microorganisms was
A. Francesco Redi.
B. Antonie van Leeuwenhoek.
C. Louis Pasteur.
D. Joseph Lister.
E. Robert Koch.
Answer: B. Antonie van Leeuwenhoek.
Rationale: Van Leeuwenhoek, a Dutch drapery merchant, perfected simple microscopes
and was the first person to observe and describe bacteria and protozoa, which he called
"animalcules" .
10. Pasteur used swan-neck flasks in his experiments to prove that
A. air had "vital forces" capable of spontaneous generation.
B. microbial fermentation could be used to make wine.
C. dust in air was a source of living microorganisms.
D. microorganisms could cause disease.
E. microorganisms could be grown in laboratory infusions.
Answer: C. dust in air was a source of living microorganisms.
Rationale: Pasteur's swan-neck flask experiment demonstrated that sterilized infusions
remained sterile unless dust (carrying microbes) entered the flask. This disproved
spontaneous generation .
