ATI RN
microbiology basic and clinical principles test bank Questions
Question 1 of 9
Which of the following bacteria is responsible for causing the disease known as pneumonia?
Correct Answer: D
Rationale: Rationale: 1. Streptococcus pneumoniae is a common cause of bacterial pneumonia. 2. Mycobacterium tuberculosis can cause a type of pneumonia called tuberculosis. 3. Escherichia coli is not typically associated with pneumonia. 4. "All of the above" includes both Streptococcus pneumoniae and Mycobacterium tuberculosis, which are known to cause pneumonia. Therefore, D is the correct answer.
Question 2 of 9
The Wasserman reaction is markedly positive (++++) in a 30-year-old man. What infectious disease is diagnosed using the Wasserman reaction?
Correct Answer: B
Rationale: The correct answer is B: Syphilis. The Wasserman reaction is a test for syphilis, specifically for detecting antibodies against the bacterium Treponema pallidum. In a 30-year-old man with a markedly positive Wasserman reaction, it indicates an active syphilis infection. Brucellosis (Choice A) is not diagnosed using the Wasserman reaction. Poliomyelitis (Choice C) is a viral infection affecting the spinal cord, not diagnosed using the Wasserman reaction. Influenza (Choice D) is a respiratory viral infection, not associated with the Wasserman reaction.
Question 3 of 9
A patient's sputum was stained using Ziehl-Neelsen method, which revealed red-colored bacilli on a blue background. What structural component of the cell is responsible for this staining property?
Correct Answer: A
Rationale: The correct answer is A: Mycolic acid. Ziehl-Neelsen method is used to stain acid-fast bacteria, such as Mycobacterium species. Mycolic acid in the cell wall of these bacteria resists decolorization, leading to red-colored bacilli on a blue background. Capsule, flagella, and endospores do not play a role in this staining property. Capsules are usually stained using special techniques, flagella are not typically visible with this stain, and endospores are stained using the Schaeffer-Fulton method.
Question 4 of 9
A source of hospital-acquired infection could be:
Correct Answer: D
Rationale: The correct answer is D because all the choices can contribute to hospital-acquired infections. New patients in the incubation period can spread infections, medical staff can inadvertently transmit infections, and contaminated medical instruments can also be a source of infections. Therefore, it is important to consider all these factors to prevent and control the spread of infections in a hospital setting.
Question 5 of 9
Francisella tularensis is a:
Correct Answer: B
Rationale: The correct answer is B: non-spore forming encapsulated gram-negative bacterium. Francisella tularensis is a non-spore forming bacterium, which rules out choices A and D. It is encapsulated, which eliminates choice C. The encapsulation of the bacterium helps it evade the host immune system, leading to its pathogenicity. This encapsulated bacterium is responsible for causing the zoonotic disease tularemia in humans.
Question 6 of 9
Which bacteria are capable of producing endospores?
Correct Answer: B
Rationale: The correct answer is B: Clostridium botulinum. This bacterium belongs to the Clostridium genus, known for its ability to produce endospores. Endospores are dormant, resistant structures that help bacteria survive harsh conditions. Staphylococcus aureus (A), Escherichia coli (C), and Neisseria gonorrhoeae (D) do not produce endospores. Staphylococcus aureus is a gram-positive bacterium known for causing various infections, but it does not form endospores. Escherichia coli is a gram-negative bacterium commonly found in the intestines of humans and animals, but it does not produce endospores. Neisseria gonorrhoeae is a gram-negative bacterium that causes the sexually transmitted infection gonorrhea, but it also does not form endospores.
Question 7 of 9
The term infection is equivalent to:
Correct Answer: A
Rationale: The correct answer is A: Infectious process. The term "infection" refers to the invasion of a host organism's body tissues by disease-causing agents, such as bacteria, viruses, or parasites. It encompasses the entire process from the initial entry of the pathogen to the host's response and resolution. Choice B, "Infectious disease," is incorrect as it specifically refers to the clinical manifestation of an infection. Choice C is irrelevant, and Choice D is incorrect as the term "infection" is indeed equivalent to the infectious process.
Question 8 of 9
A blood culture from a patient with sepsis revealed Gram-negative diplococci. The bacteria were oxidase-positive and fermentative. What is the most likely causative agent?
Correct Answer: A
Rationale: The correct answer is A: Neisseria meningitidis. Step 1: Gram-negative diplococci - characteristic of Neisseria species. Step 2: Oxidase-positive - Neisseria species are oxidase-positive. Step 3: Fermentative - Neisseria meningitidis is a fermentative bacterium. Therefore, Neisseria meningitidis is the most likely causative agent. Summary: - B: Neisseria gonorrhoeae is also a Neisseria species but is not fermentative. - C: Moraxella catarrhalis is oxidase-positive but not fermentative. - D: Haemophilus influenzae is not a Neisseria species and is not typically fermentative.
Question 9 of 9
During latency, HSV1 exists in what form:
Correct Answer: B
Rationale: During latency, HSV1 exists as episomes in neurons. This is because HSV1 establishes a lifelong latent infection in sensory neurons, where the viral genome remains as a circular episome in the nucleus. This form allows the virus to persist in a dormant state, avoiding detection by the immune system. Choice A is incorrect as HSV1 does not integrate into the host chromosome. Choice C is incorrect as latency is a well-documented phenomenon for HSV1. Choice D is incorrect as the correct answer is B.