microbiology chapter 12 test bank

Correct Answer: D

Rationale: The correct answer is D: All of the above. Hepatitis B infection can present with jaundice due to liver inflammation, elevated serum aminotransferase levels due to liver damage, and sometimes no symptoms in the acute phase. This comprehensive presentation covers the spectrum of possible clinical manifestations of hepatitis B infection. Choices A and B are correct as they are common manifestations of hepatitis B infection. Choice C is incorrect as hepatitis B infection can indeed present with symptoms, making option D the most appropriate choice.

Correct Answer: A

Rationale: The correct answer is A: Mycoplasma pneumoniae. Mycoplasma pneumoniae is a common cause of atypical pneumonia and is known to be resistant to beta-lactam antibiotics. The description of microorganisms forming microscopic colonies with a dense center resembling fried eggs is characteristic of Mycoplasma pneumoniae colonies seen on special media. Summary of other choices: B: Klebsiella pneumoniae is not typically associated with atypical pneumonia and does not exhibit the described colony morphology. C: Streptococcus pneumoniae is not resistant to beta-lactam antibiotics and does not produce colonies with the described appearance. D: Legionella pneumophila is associated with Legionnaires' disease, not atypical pneumonia, and does not form colonies resembling fried eggs.

Correct Answer: A

Rationale: The correct answer is A: Serological. Serological testing involves analyzing blood samples for specific antibodies produced in response to the pertussis infection. This method can detect past infections by identifying the presence of antibodies against the pertussis bacteria in the blood. In this case, since the doctor suspects pertussis infection in both children, serological testing can confirm if they have been exposed to the bacteria. Summary: B: Biological testing does not specifically target pertussis antibodies in the blood. C: Bacteriological testing involves culturing bacteria from samples, which may not be as sensitive for retrospective diagnosis. D: Molecular biological testing focuses on genetic material of the bacteria, which may not provide direct evidence of past infection.

Correct Answer: D

Rationale: The correct answer is D because Cytomegalovirus infections are caused by human herpesvirus 5, also known as Human Herpesvirus 5 (HHV-5) or Cytomegalovirus (CMV). This virus belongs to the Herpesviridae family, genus Betaherpesvirinae. Options A, B, and C are incorrect as they do not correspond to the specific virus responsible for causing Cytomegalovirus infections.

Correct Answer: B

Rationale: The correct answer is B: halophiles. Halophiles are bacteria that thrive in high salt environments. They have adapted to survive and grow in areas with high salt concentrations. This preference for high salt levels is what distinguishes halophiles from other types of bacteria. A: Calciphiles are bacteria that prefer high levels of calcium. C: Osmophiles are bacteria that thrive in environments with high sugar concentrations. D: Mesophiles are bacteria that prefer moderate temperature ranges for growth. In summary, the correct term for bacteria that prefer high levels of salt in their growing environment is halophiles, making choices A, C, and D incorrect in this context.