MMSC438 Exam 2 (2025) comprehensive questions and
verified detailed solutions (MULTIPLE CHOICES) |complete
solutions |A+ GRADED |100% CORRECT!!
Question 1
Which of the following is a defense mechanism of the Lower Respiratory Tract
(LRT)?
A) High pH environment
B) Absence of normal biota
C) Removal of pathogens
D) Production of lysozyme in the stomach
E) Exfoliation of skin cells
Correct Answer: C) Removal of pathogens
Rationale: Lower Respiratory Tract (LRT) defense mechanisms include
competitive inhibition by normal biota, removal of pathogens, and
immune response.
Question 2
One of the key bacterial pathogenic mechanisms is:
A) Enhanced host immune response
B) Evasion of host defenses
C) Increased oxygen absorption
D) Improved nutrient uptake
E) Accelerated peristalsis
Correct Answer: B) Evasion of host defenses
Rationale: Bacterial pathogenic mechanisms include evasion of host
defenses, adhesion to host respiratory (epithelial) cells, and toxin
production.
Question 3
Which of the following is a common route of transmission for respiratory
infections?
A) Through contaminated blood transfusions only
B) Direct person-to-person contact
C) Via insect vectors exclusively
,D) Through ingestion of contaminated water
E) Sexual intercourse
Correct Answer: B) Direct person-to-person contact
Rationale: Routes of transmission include person-to-person,
aspiration of endogenous biota, trauma, environmental and animal
reservoirs, and fomites.
Question 4
Which specimen collection method for the Lower Respiratory Tract (LRT) is
considered invasive and aims for minimum contamination?
A) Oropharyngeal swabs
B) Nasopharyngeal swabs
C) Sinus aspiration
D) Expectorated sputum
E) Bronchoalveolar lavage (BAL)
Correct Answer: E) Bronchoalveolar lavage (BAL)
Rationale: Bronchoscopy, which includes Bronchoalveolar Lavage
(BAL), is an invasive LRT collection method with minimum
contamination.
Question 5
When culturing for candidiasis in the oral cavity, the appropriate site to swab
is the:
A) Conjunctiva
B) Nasopharynx
C) Buccal mucosa, tongue, or oropharynx
D) Middle ear
E) Trachea
Correct Answer: C) Buccal mucosa, tongue, or oropharynx
Rationale: For candidiasis, the culture site should be a swab of the
buccal mucosa, tongue, or oropharynx.
,Question 6
For the diagnosis of diphtheria, where should the specimen typically be
collected?
A) Blood culture
B) Oropharyngeal swab only
C) Nasopharyngeal or throat swab
D) Tracheal aspirate
E) Sputum
Correct Answer: C) Nasopharyngeal or throat swab
Rationale: For diphtheria, the culture site should be a
nasopharyngeal or throat swab.
Question 7
If epiglottitis is suspected, which specimen collection site is crucial for
culture?
A) Throat swab
B) Nasopharyngeal swab
C) Blood culture
D) Sputum
E) Sinus aspirate
Correct Answer: C) Blood culture
Rationale: For epiglottitis, a blood culture is a crucial specimen
collection site due to the systemic nature of the infection.
Question 8
To isolate the causative agent of pertussis, the recommended specimen
collection site is the:
A) Oropharynx
B) Anterior nares
C) Posterior nasopharynx
D) Blood
E) Sputum
, Correct Answer: C) Posterior nasopharynx
Rationale: Pertussis is isolated from a posterior nasopharynx swab.
Question 9
For nasopharyngeal MRSA screening, the appropriate specimen collection
site is a swab of the:
A) Oropharynx
B) Sinuses
C) Nares (nostrils)
D) Tonsils
E) Inner cheek
Correct Answer: C) Nares (nostrils)
Rationale: Nasopharyngeal MRSA screening requires a swab of the
nares (nostrils).
Question 10
Sinusitis is often a viral infection leading to a secondary bacterial infection.
Which pathogen is most commonly associated with these secondary
bacterial infections?
A) Pseudomonas aeruginosa
B) Staphylococcus epidermidis
C) Streptococcus pneumoniae
D) Neisseria meningitidis
E) Klebsiella pneumoniae
Correct Answer: C) Streptococcus pneumoniae
Rationale: Common causes of bacterial sinusitis following a viral
infection (common cold) include S. pneumoniae, H. influenzae, and
M. catarrhalis.
Question 11
Pharyngitis, common in school-aged children, is typically treated with:
A) Amantadine
B) Penicillin
verified detailed solutions (MULTIPLE CHOICES) |complete
solutions |A+ GRADED |100% CORRECT!!
Question 1
Which of the following is a defense mechanism of the Lower Respiratory Tract
(LRT)?
A) High pH environment
B) Absence of normal biota
C) Removal of pathogens
D) Production of lysozyme in the stomach
E) Exfoliation of skin cells
Correct Answer: C) Removal of pathogens
Rationale: Lower Respiratory Tract (LRT) defense mechanisms include
competitive inhibition by normal biota, removal of pathogens, and
immune response.
Question 2
One of the key bacterial pathogenic mechanisms is:
A) Enhanced host immune response
B) Evasion of host defenses
C) Increased oxygen absorption
D) Improved nutrient uptake
E) Accelerated peristalsis
Correct Answer: B) Evasion of host defenses
Rationale: Bacterial pathogenic mechanisms include evasion of host
defenses, adhesion to host respiratory (epithelial) cells, and toxin
production.
Question 3
Which of the following is a common route of transmission for respiratory
infections?
A) Through contaminated blood transfusions only
B) Direct person-to-person contact
C) Via insect vectors exclusively
,D) Through ingestion of contaminated water
E) Sexual intercourse
Correct Answer: B) Direct person-to-person contact
Rationale: Routes of transmission include person-to-person,
aspiration of endogenous biota, trauma, environmental and animal
reservoirs, and fomites.
Question 4
Which specimen collection method for the Lower Respiratory Tract (LRT) is
considered invasive and aims for minimum contamination?
A) Oropharyngeal swabs
B) Nasopharyngeal swabs
C) Sinus aspiration
D) Expectorated sputum
E) Bronchoalveolar lavage (BAL)
Correct Answer: E) Bronchoalveolar lavage (BAL)
Rationale: Bronchoscopy, which includes Bronchoalveolar Lavage
(BAL), is an invasive LRT collection method with minimum
contamination.
Question 5
When culturing for candidiasis in the oral cavity, the appropriate site to swab
is the:
A) Conjunctiva
B) Nasopharynx
C) Buccal mucosa, tongue, or oropharynx
D) Middle ear
E) Trachea
Correct Answer: C) Buccal mucosa, tongue, or oropharynx
Rationale: For candidiasis, the culture site should be a swab of the
buccal mucosa, tongue, or oropharynx.
,Question 6
For the diagnosis of diphtheria, where should the specimen typically be
collected?
A) Blood culture
B) Oropharyngeal swab only
C) Nasopharyngeal or throat swab
D) Tracheal aspirate
E) Sputum
Correct Answer: C) Nasopharyngeal or throat swab
Rationale: For diphtheria, the culture site should be a
nasopharyngeal or throat swab.
Question 7
If epiglottitis is suspected, which specimen collection site is crucial for
culture?
A) Throat swab
B) Nasopharyngeal swab
C) Blood culture
D) Sputum
E) Sinus aspirate
Correct Answer: C) Blood culture
Rationale: For epiglottitis, a blood culture is a crucial specimen
collection site due to the systemic nature of the infection.
Question 8
To isolate the causative agent of pertussis, the recommended specimen
collection site is the:
A) Oropharynx
B) Anterior nares
C) Posterior nasopharynx
D) Blood
E) Sputum
, Correct Answer: C) Posterior nasopharynx
Rationale: Pertussis is isolated from a posterior nasopharynx swab.
Question 9
For nasopharyngeal MRSA screening, the appropriate specimen collection
site is a swab of the:
A) Oropharynx
B) Sinuses
C) Nares (nostrils)
D) Tonsils
E) Inner cheek
Correct Answer: C) Nares (nostrils)
Rationale: Nasopharyngeal MRSA screening requires a swab of the
nares (nostrils).
Question 10
Sinusitis is often a viral infection leading to a secondary bacterial infection.
Which pathogen is most commonly associated with these secondary
bacterial infections?
A) Pseudomonas aeruginosa
B) Staphylococcus epidermidis
C) Streptococcus pneumoniae
D) Neisseria meningitidis
E) Klebsiella pneumoniae
Correct Answer: C) Streptococcus pneumoniae
Rationale: Common causes of bacterial sinusitis following a viral
infection (common cold) include S. pneumoniae, H. influenzae, and
M. catarrhalis.
Question 11
Pharyngitis, common in school-aged children, is typically treated with:
A) Amantadine
B) Penicillin
