microbiology an introduction 12th edition test bank

Correct Answer: D

Rationale: The correct answer is D (All of the above) because different bacteria can cause pneumonia. Streptococcus pneumoniae is the most common cause of community-acquired pneumonia. Mycobacterium tuberculosis causes tuberculosis, which can lead to pneumonia. Pseudomonas aeruginosa is a common cause of hospital-acquired pneumonia. Therefore, all three bacteria can be responsible for causing pneumonia in different contexts. Choices A, B, and C are incorrect because each bacterium individually can cause pneumonia, so selecting only one option would not cover the full spectrum of bacterial causes of pneumonia.

Correct Answer: A

Rationale: The correct answer is A: Gp120. Gp120 is a glycoprotein on the surface of the HIV virus that specifically binds to the CD4 receptor on target cells. This binding is essential for the virus to enter the host cell and initiate the infection process. Gp41 is another glycoprotein on the virus that helps with membrane fusion, not binding to CD4. Gp32 and Gp55 are not involved in the specific binding of HIV to CD4 molecules. So, A is correct as it directly plays a key role in the initial attachment of HIV to target cells.

Correct Answer: B

Rationale: The correct answer is B: Isolation on cell cultures. This method is the gold standard for routine mumps diagnosis as it involves isolating the virus in cell cultures to confirm the presence of the mumps virus. PCR (choice A) is used for detecting viral RNA, not for routine diagnosis. ELISA (choice C) detects antibodies, not the virus itself. Immunofluorescence method (choice D) is used for visualizing viral antigens but is not as reliable as isolating the virus in cell cultures for diagnosis.

Correct Answer: D

Rationale: The correct answer is D (All of the above) because different bacteria can cause pneumonia. Streptococcus pneumoniae is the most common cause of community-acquired pneumonia. Mycobacterium tuberculosis causes tuberculosis, which can lead to pneumonia. Pseudomonas aeruginosa is a common cause of hospital-acquired pneumonia. Therefore, all three bacteria can be responsible for causing pneumonia in different contexts. Choices A, B, and C are incorrect because each bacterium individually can cause pneumonia, so selecting only one option would not cover the full spectrum of bacterial causes of pneumonia.

Correct Answer: A

Rationale: The correct answer is A: Genus Shigella. Shigella is known to be the causative agent of bacterial dysentery. It invades the intestinal lining, leading to symptoms like severe diarrhea and abdominal cramps. Salmonella (choice B) typically causes food poisoning, not dysentery. Klebsiella (choice C) is associated with pneumonia and urinary tract infections, not dysentery. "None of the above" (choice D) is incorrect as Shigella does belong to a specific genus responsible for bacterial dysentery.