Brock Biology of Microorganisms 2025
Exam Preparation and Practice Questions
An infection of the vaginal mucosa resulting in an abnormal discharge and offensive odor
or itching is referred to as:
A. chorioamnionitis
B. bartholinitis
C. cervicitis
D. vaginitis
Rationale: Vaginitis is inflammation of the vaginal mucosa, leading to discharge, odor, or
itching. The other options involve different reproductive organs (chorioamnionitis—uterus,
bartholinitis—Bartholin glands, cervicitis—cervix).
An infection that results when cervical microorganisms travel upward to the endometrium,
fallopian tubes, and other pelvic structures is:
A. chorioamnionitis
B. bartholinitis
C. cervicitis
D. PID
Rationale: Pelvic Inflammatory Disease (PID) affects upper genital structures like the uterus and
fallopian tubes. Others are localized infections.
Match the condition with its definition:
-Inflammation of the vaginal mucosa resulting in discharge → Vaginitis
-Polymicrobial vaginitis with foul-smelling discharge → Bacterial vaginosis
-Infection of uterus during pregnancy → Chorioamnionitis
-Inflammation of the testicles (mumps virus) → Orchitis
Correct match: 3, 1, 2, 4
Rationale: Each term matches its specific anatomical infection.
Match the disease with the causative agent:
-Anaerobic, polymicrobic infection from normal genital flora → Bartholinitis
-Chlamydia trachomatis → Nongonococcal urethritis
,-Gardnerella, Prevotella, Porphyromonas, Mobiluncus → Bacterial vaginosis
-Neisseria gonorrhoeae → Cervicitis
-Neisseria gonorrhoeae & Chlamydia trachomatis → Epididymitis
-Escherichia coli → Prostatitis
-Mumps virus → Orchitis
Correct match: 6, 2, 3, 5, 4, 7, 1
Rationale: Each agent corresponds to its classic infection site and pathogen type.
The normal flora of the adult large bowel consists predominantly of:
A. anaerobic species
B. Staphylococcus
C. Enterococcus
D. Enterobacteriaceae
Rationale: Anaerobes like Bacteroides dominate gut flora.
The transport medium that best preserves most intestinal bacterial pathogens is:
A. buffered glycerol
B. rectal culture swab
C. Cary-Blair
D. Campylobacter thioglycollate broth
Rationale: Cary-Blair maintains viability of enteric pathogens during transport.
Stool for routine culture should be examined for:
A. Campylobacter, Salmonella, and Shigella spp.
B. Salmonella and Shigella spp.
C. Campylobacter and Vibrio spp.
D. Salmonella, Shigella, and Vibrio spp.
Rationale: These are the three main bacterial pathogens screened in stool cultures.
Cultures for Campylobacter jejuni/coli should be incubated in:
A. capnophilic atmosphere at 42°C
B. microaerophilic at 35°C
, C. room air at 35°C
D. microaerophilic atmosphere at 42°C
Rationale: Campylobacter grows best at 42°C under low oxygen (microaerophilic) conditions.
Sheep blood agar in fecal culture serves for:
. A. Evaluation of general flora and predominant species
Rationale: Blood agar allows observation of hemolytic and predominant flora
MacConkey agar serves for:
B. Selection of enteric pathogens such as Salmonella, Aeromonas, and others
Rationale: MacConkey is selective for Gram-negative enteric bacteria.
XLD agar serves for:
C. Inhibition of normal flora and selection of enteric pathogens
Rationale: Xylose Lysine Deoxycholate agar isolates Salmonella and Shigella.
Campylobacter thioglycollate broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
Rationale: Enrichment media increase pathogen recovery by suppressing competing flora.
Selenite broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
Rationale: Promotes Salmonella growth over normal flora.
Gram-negative broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
Exam Preparation and Practice Questions
An infection of the vaginal mucosa resulting in an abnormal discharge and offensive odor
or itching is referred to as:
A. chorioamnionitis
B. bartholinitis
C. cervicitis
D. vaginitis
Rationale: Vaginitis is inflammation of the vaginal mucosa, leading to discharge, odor, or
itching. The other options involve different reproductive organs (chorioamnionitis—uterus,
bartholinitis—Bartholin glands, cervicitis—cervix).
An infection that results when cervical microorganisms travel upward to the endometrium,
fallopian tubes, and other pelvic structures is:
A. chorioamnionitis
B. bartholinitis
C. cervicitis
D. PID
Rationale: Pelvic Inflammatory Disease (PID) affects upper genital structures like the uterus and
fallopian tubes. Others are localized infections.
Match the condition with its definition:
-Inflammation of the vaginal mucosa resulting in discharge → Vaginitis
-Polymicrobial vaginitis with foul-smelling discharge → Bacterial vaginosis
-Infection of uterus during pregnancy → Chorioamnionitis
-Inflammation of the testicles (mumps virus) → Orchitis
Correct match: 3, 1, 2, 4
Rationale: Each term matches its specific anatomical infection.
Match the disease with the causative agent:
-Anaerobic, polymicrobic infection from normal genital flora → Bartholinitis
-Chlamydia trachomatis → Nongonococcal urethritis
,-Gardnerella, Prevotella, Porphyromonas, Mobiluncus → Bacterial vaginosis
-Neisseria gonorrhoeae → Cervicitis
-Neisseria gonorrhoeae & Chlamydia trachomatis → Epididymitis
-Escherichia coli → Prostatitis
-Mumps virus → Orchitis
Correct match: 6, 2, 3, 5, 4, 7, 1
Rationale: Each agent corresponds to its classic infection site and pathogen type.
The normal flora of the adult large bowel consists predominantly of:
A. anaerobic species
B. Staphylococcus
C. Enterococcus
D. Enterobacteriaceae
Rationale: Anaerobes like Bacteroides dominate gut flora.
The transport medium that best preserves most intestinal bacterial pathogens is:
A. buffered glycerol
B. rectal culture swab
C. Cary-Blair
D. Campylobacter thioglycollate broth
Rationale: Cary-Blair maintains viability of enteric pathogens during transport.
Stool for routine culture should be examined for:
A. Campylobacter, Salmonella, and Shigella spp.
B. Salmonella and Shigella spp.
C. Campylobacter and Vibrio spp.
D. Salmonella, Shigella, and Vibrio spp.
Rationale: These are the three main bacterial pathogens screened in stool cultures.
Cultures for Campylobacter jejuni/coli should be incubated in:
A. capnophilic atmosphere at 42°C
B. microaerophilic at 35°C
, C. room air at 35°C
D. microaerophilic atmosphere at 42°C
Rationale: Campylobacter grows best at 42°C under low oxygen (microaerophilic) conditions.
Sheep blood agar in fecal culture serves for:
. A. Evaluation of general flora and predominant species
Rationale: Blood agar allows observation of hemolytic and predominant flora
MacConkey agar serves for:
B. Selection of enteric pathogens such as Salmonella, Aeromonas, and others
Rationale: MacConkey is selective for Gram-negative enteric bacteria.
XLD agar serves for:
C. Inhibition of normal flora and selection of enteric pathogens
Rationale: Xylose Lysine Deoxycholate agar isolates Salmonella and Shigella.
Campylobacter thioglycollate broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
Rationale: Enrichment media increase pathogen recovery by suppressing competing flora.
Selenite broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
Rationale: Promotes Salmonella growth over normal flora.
Gram-negative broth serves for:
D. Enrichment for enteric pathogens such as Salmonella and others
