ENVS 2126 Exam 4 Practice Questions & Answers
(Verified Update)
This comprehensive study guide covers the core domains tested
on ENVS 2126 Exam 4: Pathogens, Environmental Health &
Applied Microbiology at Louisiana State University. It includes
original practice questions with detailed rationales, organized
by the core exam domains: Epidemiology & Public Health,
Waterborne & Foodborne Pathogens, Soil & Plant
Microbiology, Environmental Biotechnology & Energy, and
Molecular Biology & Genetics.
Exam Overview & Blueprint:
Parameter Details
Course Environmental and Anthropogenic Impacts of Microbes (ENVS 2126)
Exam
Multiple-choice, true/false, and short-answer questions
Format
Epidemiology, Vibrio pathogens, Bacillus anthracis, botulinum toxin, soil microbiology,
Core Topics
rhizosphere, biofilms, wastewater treatment, bioremediation, molecular genetics
Key
Environmental Microbiology, 3rd Edition (Pepper, Gerba, Gentry)
Textbook
,Parameter Details
Application-based case studies, pathogen identification, molecular biology calculations,
2026 Focus
environmental health scenarios
Section 1: Epidemiology & Public Health
Q1. Each week, the U.S. Centers for Disease Control and
Prevention (CDC) publish the Morbidity and Mortality Weekly
Report to document infectious diseases. Why might they report
on morbidity and mortality separately instead of just cases in
general?
A) Because although morbidity is pathology or symptoms from
disease, it gives no information on death from the disease
B) Because morbidity and mortality are the same thing
C) Because mortality is more important than morbidity
D) Because morbidity only refers to death
Answer: A
Rationale: Morbidity refers to the pathology or symptoms from
disease, while mortality refers to death from the disease.
Reporting them separately provides a more complete picture of
the disease burden. Morbidity data alone gives no information
on death rates.
,Q2. What is the difference between an epidemic and a
pandemic?
A) An epidemic is a sudden increase in infectious diseases in a
large number of people in a population, and a pandemic is
when this increase occurs on a global scale
B) An epidemic is global; a pandemic is local
C) An epidemic is caused by bacteria; a pandemic is caused by
viruses
D) There is no difference
Answer: A
Rationale: An epidemic is a sudden increase in infectious
diseases in a large number of people in a population. A
pandemic is when this increase occurs on a global scale.
Q3. Why is there so much research done on samples of human
stools compared to other body parts?
A) It is less invasive and gets at diet
B) It is more dangerous
C) It is more expensive
D) It is the only sample available
Answer: A
Rationale: Stool samples are less invasive to collect than
samples from other body parts (e.g., biopsies) and provide
information about diet and gut microbiome composition.
, Q4. On average, about how many different bacterial species do
you have in your gut right now?
A) 160
B) 10
C) 10,000
D) 1
Answer: A
Rationale: On average, humans harbor approximately 160
different bacterial species in their gut.
Q5. Of all the cells that make up the human body, how many of
them are actually bacterial?
A) A little more than half
B) Less than 10%
C) About 25%
D) None
Answer: A
Rationale: Bacterial cells outnumber human cells in the body,
accounting for a little more than half of all cells.
Q6. Over the years, there have been several Vibrio outbreaks
related to people eating raw oysters harvested from the same
location, e.g., Galveston Bay. These are examples of ___.
A) Common-source epidemics
B) Propagated epidemics
(Verified Update)
This comprehensive study guide covers the core domains tested
on ENVS 2126 Exam 4: Pathogens, Environmental Health &
Applied Microbiology at Louisiana State University. It includes
original practice questions with detailed rationales, organized
by the core exam domains: Epidemiology & Public Health,
Waterborne & Foodborne Pathogens, Soil & Plant
Microbiology, Environmental Biotechnology & Energy, and
Molecular Biology & Genetics.
Exam Overview & Blueprint:
Parameter Details
Course Environmental and Anthropogenic Impacts of Microbes (ENVS 2126)
Exam
Multiple-choice, true/false, and short-answer questions
Format
Epidemiology, Vibrio pathogens, Bacillus anthracis, botulinum toxin, soil microbiology,
Core Topics
rhizosphere, biofilms, wastewater treatment, bioremediation, molecular genetics
Key
Environmental Microbiology, 3rd Edition (Pepper, Gerba, Gentry)
Textbook
,Parameter Details
Application-based case studies, pathogen identification, molecular biology calculations,
2026 Focus
environmental health scenarios
Section 1: Epidemiology & Public Health
Q1. Each week, the U.S. Centers for Disease Control and
Prevention (CDC) publish the Morbidity and Mortality Weekly
Report to document infectious diseases. Why might they report
on morbidity and mortality separately instead of just cases in
general?
A) Because although morbidity is pathology or symptoms from
disease, it gives no information on death from the disease
B) Because morbidity and mortality are the same thing
C) Because mortality is more important than morbidity
D) Because morbidity only refers to death
Answer: A
Rationale: Morbidity refers to the pathology or symptoms from
disease, while mortality refers to death from the disease.
Reporting them separately provides a more complete picture of
the disease burden. Morbidity data alone gives no information
on death rates.
,Q2. What is the difference between an epidemic and a
pandemic?
A) An epidemic is a sudden increase in infectious diseases in a
large number of people in a population, and a pandemic is
when this increase occurs on a global scale
B) An epidemic is global; a pandemic is local
C) An epidemic is caused by bacteria; a pandemic is caused by
viruses
D) There is no difference
Answer: A
Rationale: An epidemic is a sudden increase in infectious
diseases in a large number of people in a population. A
pandemic is when this increase occurs on a global scale.
Q3. Why is there so much research done on samples of human
stools compared to other body parts?
A) It is less invasive and gets at diet
B) It is more dangerous
C) It is more expensive
D) It is the only sample available
Answer: A
Rationale: Stool samples are less invasive to collect than
samples from other body parts (e.g., biopsies) and provide
information about diet and gut microbiome composition.
, Q4. On average, about how many different bacterial species do
you have in your gut right now?
A) 160
B) 10
C) 10,000
D) 1
Answer: A
Rationale: On average, humans harbor approximately 160
different bacterial species in their gut.
Q5. Of all the cells that make up the human body, how many of
them are actually bacterial?
A) A little more than half
B) Less than 10%
C) About 25%
D) None
Answer: A
Rationale: Bacterial cells outnumber human cells in the body,
accounting for a little more than half of all cells.
Q6. Over the years, there have been several Vibrio outbreaks
related to people eating raw oysters harvested from the same
location, e.g., Galveston Bay. These are examples of ___.
A) Common-source epidemics
B) Propagated epidemics
