Lecture 6

Question 1

What is a distinctive feature of mycobacteria’s cell walls that affects their staining properties?

A. Low lipid content
B. Presence of peptidoglycan
C. High lipid content
D. Lack of a cell wall

Answer 1

C. High lipid content

Question 2

Which disease is caused by Mycobacterium leprae?

A. Tuberculosis
B. Leprosy
C. Diphtheria
D. Typhoid

Answer 2

B. Leprosy

Question 3

What is the main mode of transmission for Mycobacterium tuberculosis?

A. Contaminated food
B. Insect bites
C. Aerosol droplets
D. Direct skin contact

Answer 3

C. Aerosol droplets

Question 4

What type of hypersensitivity is the tuberculin skin test (Mantoux test) an example of?

A. Type I
B. Type II
C. Type III
D. Type IV

Answer 4

D. Type IV

Question 4

Which organism is known to cause syphilis?

A. Mycobacterium tuberculosis
B. Treponema pallidum
C. Neisseria gonorrhoeae
D. Helicobacter pylori

Answer 4

B. Treponema pallidum

Question 5

What is the key virulence factor for the pathogenicity of Treponema pallidum?

A. Capsule
B. Endotoxin
C. Flagellum
D. Spirochete structure

Answer 5

D. Spirochete structure

Question 6

Mycobacterium tuberculosis is classified as which type of organism based on its oxygen requirements?

A. Obligate aerobe
B. Obligate anaerobe
C. Facultative anaerobe
D. Microaerophile

Answer 6

A. Obligate aerobe

Question 7

What is the most common clinical presentation of primary tuberculosis?

A. Pneumonia
B. Asymptomatic infection
C. Severe cough with blood
D. High fever and night sweats

Answer 7

B. Asymptomatic infection

Question 7

Which staining technique is used to identify acid-fast bacilli like mycobacteria?

A. Gram stain
B. Ziehl-Neelsen stain
C. India ink stain
D. PAS stain

Answer 7

B. Ziehl-Neelsen stain

Question 8

Atypical mycobacteria are most likely to cause disease in which group of individuals?

A. Healthy adults
B. Immunocompromised individuals
C. Newborns
D. Elderly individuals without other health issues

Answer 8

B. Immunocompromised individuals

Question 9

Which test is used to diagnose latent tuberculosis infection?

A. PCR test
B. Mantoux test
C. Sputum culture
D. Chest X-ray

Answer 9

B. Mantoux test

Question 10

Which part of the body is primarily affected by lepromatous leprosy?

A. Lungs
B. Skin and nerves
C. Gastrointestinal tract
D. Liver

Answer 10

B. Skin and nerves

Question 10

Spirochetes like Treponema pallidum are best described as:

A. Gram-positive cocci
B. Gram-negative rods
C. Spiral-shaped bacteria
D. Obligate anaerobes

Answer 10

C. Spiral-shaped bacteria

Question 11

Which test is used to confirm syphilis in a patient suspected based on symptoms?

A. Rapid plasma reagin (RPR)
B. White blood cell count
C. Chest X-ray
D. Stool culture

Answer 11

A. Rapid plasma reagin (RPR)

Question 12

Treatment for leprosy involves:

A. Antiviral medications
B. Antifungal medications
C. Antibiotics
D. Antiparasitic medications

Answer 12

C. Antibiotics

Question 13

What is a common complication associated with lepromatous leprosy?

A. Severe diarrhea
B. Frequent upper respiratory infections
C. Neurological damage
D. Cardiovascular disease

Answer 13

C. Neurological damage

Question 14

Which condition can be confused with tuberculosis due to similar symptoms?

A. Asthma
B. Pneumonia
C. Bronchitis
D. Allergic rhinitis

Answer 14

B. Pneumonia

Question 15

Spirochetes are unique in being:

A. Resistant to all antibiotics
B. Visible under regular light microscopy without staining
C. Capable of surviving outside a host for long periods
D. Difficult to culture in vitro

Answer 15

D. Difficult to culture in vitro

Question 16

What indicates a positive result on a tuberculin skin test?

A. A red bump at the injection site
B. Fever and night sweats within 48 hours
C. A clear fluid blister at the injection site
D. Induration (hardened area) of 10 mm or more

Answer 16

D. Induration (hardened area) of 10 mm or more

Question 16

The decline in the number of tuberculosis cases in the US is attributed to:

A. Natural immunity in the population
B. Improved public health and medical treatments
C. The discontinuation of the BCG vaccine
D. Changes in the pathogenicity of the bacteria

Answer 16

B. Improved public health and medical treatments