Which one belongs to genus Orthopoxvirus

Questions 80

ATI RN

ATI RN Test Bank

microbiology an introduction 13th edition test bank Questions

Question 1 of 9

Which one belongs to genus Orthopoxvirus

Correct Answer: D

Rationale: The correct answer is D, All of these. Orthopoxvirus genus includes Vaccinia, Smallpox, and Cowpox viruses. They share similar characteristics such as brick-shaped virions and double-stranded DNA genomes. Vaccinia virus is used in smallpox vaccine, Smallpox virus caused the eradicated disease, and Cowpox virus can infect both animals and humans. Therefore, all three viruses belong to the Orthopoxvirus genus. Choices A, B, and C are incorrect because they each represent a different virus from the genus Orthopoxvirus.

Question 2 of 9

Which of the following specific immune mechanisms offer NO protection against infection

Correct Answer: C

Rationale: Correct Answer: C - Immunological tolerance to the pathogen Rationale: 1. Immunological tolerance is when the immune system does not mount a response against specific antigens to prevent autoimmunity. 2. In the context of infection, tolerance to the pathogen means the immune system does not recognize the pathogen as a threat and does not initiate a protective response. 3. This lack of response leaves the host vulnerable to infection as there is no specific immune defense mechanism activated against the pathogen. Summary of incorrect choices: A: Opsonic action of antibody - enhances phagocytosis of pathogens B: Viral neutralization by specific antibody - prevents viral entry into host cells D: Neutralization of protein exotoxin - prevents the harmful effects of toxins produced by pathogens.

Question 3 of 9

A Gram-negative, comma-shaped bacterium was isolated from a patient with cholera. What is the most likely microorganism?

Correct Answer: A

Rationale: The correct answer is A: Vibrio cholerae. 1. Vibrio cholerae is a Gram-negative, comma-shaped bacterium known to cause cholera. 2. Shigella dysenteriae causes dysentery, not cholera. 3. Salmonella typhi causes typhoid fever, not cholera. 4. Campylobacter jejuni causes gastroenteritis, not cholera. Therefore, based on the symptoms presented and the characteristics of the bacterium, Vibrio cholerae is the most likely microorganism.

Question 4 of 9

A patient suffering from syphilis was prescribed a drug the action of which based upon disturbed generation of murein leading to death of the causative agent. What drug is it?

Correct Answer: A

Rationale: The correct answer is A: Benzylpenicillin sodium salt. Benzylpenicillin is a beta-lactam antibiotic that inhibits the synthesis of bacterial cell walls by disrupting the formation of murein (peptidoglycan), leading to bacterial cell death. This mechanism specifically targets the causative agent of syphilis, Treponema pallidum. - Choice B: Bijochinol is not a known drug used to treat syphilis. - Choice C: Ciprofloxacin is a fluoroquinolone antibiotic that works by inhibiting bacterial DNA replication and is not the first-line treatment for syphilis. - Choice D: Azithromycin is a macrolide antibiotic that interferes with bacterial protein synthesis and is commonly used to treat other infections but is not the preferred treatment for syphilis.

Question 5 of 9

A Gram-positive cocci in chains was isolated from a patient with a throat infection. The bacteria were catalase-negative and beta-hemolytic. What is the most likely causative agent?

Correct Answer: A

Rationale: The correct answer is A: Streptococcus pyogenes. Rationale: 1. Gram-positive cocci in chains: S. pyogenes is a Gram-positive cocci in chains. 2. Catalase-negative: S. pyogenes is catalase-negative. 3. Beta-hemolytic: S. pyogenes exhibits beta-hemolysis. Summary of other choices: B: Streptococcus pneumoniae is alpha-hemolytic and optochin-sensitive. C: Enterococcus faecalis is catalase-negative, but not typically beta-hemolytic. D: Staphylococcus aureus is catalase-positive and coagulase-positive.

Question 6 of 9

Characteristic features of infectious process:

Correct Answer: D

Rationale: Step-by-step rationale: 1. Infectious process triggers an immune response to fight off the invading pathogen. 2. The immune response can lead to inflammation, fever, and production of antibodies. 3. Hypersensitivity reactions can also occur in response to the infection. 4. Options A, B, and C are not defining features of the infectious process. Summary: Option D is correct because an infectious process typically leads to an immune response and possibly hypersensitivity reactions. Options A, B, and C are incorrect as they do not specifically relate to the immune response or hypersensitivity reactions in the context of an infectious process.

Question 7 of 9

A 32-year-old patient who lives in the countryside consulted a doctor about a painful swelling and a fistula in the submandibular region. Examination revealed an infiltration with a fistula discharging thick pus and containing white granules. On dissection the infiltration tissues turned out to be dense, yellow-green and had honeycomb structure because of multiple abscesses. What is the most likely diagnosis?

Correct Answer: A

Rationale: The most likely diagnosis is Actinomycosis. This is because the patient's presentation of a painful swelling with a fistula containing white granules and yellow-green honeycomb-like tissue is classic for Actinomycosis. Actinomyces is a gram-positive anaerobic bacterium that forms sulfur granules in tissues. Tuberculosis (B) typically presents with caseating granulomas, not sulfur granules. Leprosy (C) presents with skin lesions and nerve damage, not characteristic of this case. Syphilis (D) usually presents with painless ulcers and rash, not the painful swelling and fistula seen in this patient.

Question 8 of 9

Sputum smears of a patient with chronic pulmonary disease were stained by Ziehl-Neelsen method and analyzed in the bacteriological laboratory. Microscopy revealed red bacillus. What property of tuberculosis myobacteria was found?

Correct Answer: A

Rationale: The correct answer is A: Acid resistance. Tuberculosis mycobacteria have a unique cell wall structure that makes them resistant to acid-fast staining methods like Ziehl-Neelsen. This is due to the high lipid content of their cell walls, specifically mycolic acids, which prevent the penetration of stains and acids. The red bacilli observed in the smear indicate that the mycobacteria retained the primary stain (carbolfuchsin) after acid-alcohol decolorization, confirming their acid resistance. Summary: - Choice A: Acid resistance is correct due to the unique cell wall structure of tuberculosis mycobacteria. - Choice B: Alkali resistance is incorrect as mycobacteria are not known for being resistant to alkalis. - Choice C: Alcohol resistance is incorrect as mycobacteria are not specifically resistant to alcohols. - Choice D: Encapsulation is incorrect as mycobacteria are not encapsulated bacteria.

Question 9 of 9

Which bacteria are responsible for causing foodborne illnesses?

Correct Answer: D

Rationale: The correct answer is D, "All of the above," because all three bacteria (Salmonella enterica, Clostridium botulinum, Escherichia coli) are known to cause foodborne illnesses. Salmonella causes symptoms like diarrhea, fever, and abdominal cramps. Clostridium botulinum produces a toxin leading to botulism, a severe illness affecting the nervous system. Escherichia coli strains like E. coli O157:H7 can cause food poisoning with symptoms such as bloody diarrhea. Therefore, all the listed bacteria can cause foodborne illnesses due to their ability to contaminate food and infect individuals.

Access More Questions!

ATI RN Basic


$89/ 30 days

ATI RN Premium


$150/ 90 days