microbiology chapter 12 test bank

Correct Answer: A

Rationale: The correct answer is A: 1. Water testing facilities typically handle low-risk microorganisms, hence requiring Biosafety Level 1. BSL 1 is suitable for working with well-characterized agents not known to consistently cause disease in healthy adults. BSL 2 is for moderate-risk agents, BSL 3 for high-risk agents, and BSL 4 for dangerous pathogens. Therefore, choices B, C, and D are incorrect for water testing facilities due to the low risk involved in handling the microorganisms found in water samples.

Correct Answer: D

Rationale: The correct answer is D. Cytoplasmic inclusions in bacteria refer to substances like granules. These granules can be excess products of metabolism or reserve substances stored for future use. Therefore, all of the choices are correct as cytoplasmic inclusions can be any of these substances. A is correct as it directly refers to cytoplasmic inclusions. B is correct as some granules can be excess metabolic products. C is correct as certain granules can serve as reserve substances. Therefore, the correct answer is D, as it encompasses all the possible types of substances found as cytoplasmic inclusions in bacteria.

Correct Answer: A

Rationale: The correct answer is A: 1. Water testing facilities typically handle low-risk microorganisms, hence requiring Biosafety Level 1. BSL 1 is suitable for working with well-characterized agents not known to consistently cause disease in healthy adults. BSL 2 is for moderate-risk agents, BSL 3 for high-risk agents, and BSL 4 for dangerous pathogens. Therefore, choices B, C, and D are incorrect for water testing facilities due to the low risk involved in handling the microorganisms found in water samples.

Correct Answer: A

Rationale: The correct answer is A: Clostridium botulinum. This bacterium produces the botulinum neurotoxin, which causes paralysis by blocking the release of acetylcholine at neuromuscular junctions. Clostridium perfringens causes gas gangrene, not paralysis. Escherichia coli is associated with gastrointestinal infections, not paralysis. Staphylococcus aureus produces enterotoxins causing food poisoning, not paralysis. Therefore, Clostridium botulinum is the correct choice based on its well-known association with paralysis due to botulinum neurotoxin production.

Correct Answer: D

Rationale: The correct answer is D, "All of the above," because all three bacteria listed (Vibrio cholerae, Clostridium difficile, Escherichia coli) produce toxins that can cause severe gastrointestinal illness. Vibrio cholerae produces cholera toxin leading to severe diarrhea. Clostridium difficile produces toxins causing antibiotic-associated diarrhea. Escherichia coli can produce toxins such as Shiga toxin causing severe gastrointestinal symptoms. Therefore, all the options listed are correct in producing toxins that can result in severe gastrointestinal illness.