microbiology chapter 14 test bank

Correct Answer: C

Rationale: The correct answer is C. Bacterial spores are NOT used for cell division. Bacterial spores are dormant, resistant forms of bacteria that are formed in response to harsh environmental conditions. They are not involved in cell division but rather serve as a survival mechanism for the bacteria. A: They can deform the cell or not - This is true. Bacterial spores can deform the cell or not depending on the conditions. B: They can be terminal, subterminal, and central - This is true. Bacterial spores can be located at different positions within the bacterial cell. D: They are formed for 6-8h - This is incorrect. The formation of bacterial spores can take variable time periods depending on the species and environmental conditions.

Correct Answer: C

Rationale: The correct answer is C: Fecal enterococcus. In a drugstore setting, finding a fecal-indicative microorganism like fecal enterococcus indicates a potential contamination from fecal matter, which poses a significant health risk. Staphylococcus aureus (Choice A) and α-haemolytic streptococcus (Choice D) are not typically indicative of fecal contamination. Colon bacillus (Choice B) is a common bacterium found in the gut but is not specifically indicative of fecal contamination. Therefore, choice C, fecal enterococcus, is the most appropriate microorganism indicating unsanitary conditions in a drugstore.

Correct Answer: B

Rationale: The correct answer is B: Pseudomonas aeruginosa. P. aeruginosa is known for producing pyocyanin, a green pigment. This bacterium is commonly associated with infections in immunocompromised individuals. Staphylococcus aureus (choice A) produces golden-yellow pigments, not green. Escherichia coli (choice C) and Clostridium difficile (choice D) do not produce pyocyanin. Therefore, the correct choice is B based on the characteristic pigment produced by Pseudomonas aeruginosa.

Correct Answer: C

Rationale: Rationale: 1. Vaccinia is a laboratory product used in smallpox vaccination. 2. Variola is the virus that causes smallpox, not a laboratory product. 3. Monkeypox is a naturally occurring virus, not a laboratory product. 4. Cowpox can be found in nature and is used in vaccine production, but it is not a laboratory product like Vaccinia.

Correct Answer: D

Rationale: The correct answer is D: rRNA. Bacterial ribosomes consist mainly of ribosomal RNA (rRNA), which plays a crucial role in protein synthesis. Ribosomes are composed of rRNA and proteins, with rRNA being the major component. rRNA serves as the structural and catalytic component of the ribosome, aiding in the binding of mRNA and tRNA during translation. Carbohydrates (A) and lipids (B) are not primary components of ribosomes, and DNA (C) is not found in ribosomes as they are involved in storing genetic information, not in protein synthesis.