Foundations in Microbiology Test Bank

Correct Answer: A

Rationale: The correct answer is A: Fluconazole. 1. Fluconazole is an antifungal agent effective against Candida species commonly causing candidiasis. 2. Streptomycin (B) is an antibiotic used for bacterial infections, not fungal. 3. Phthalylsulfathiazole (C) is an antibacterial agent, not antifungal. 4. Ampicillin (D) is a ?-lactam antibiotic, which can actually contribute to fungal infections like candidiasis.

Correct Answer: A

Rationale: Osmosis is the correct answer because it is the process by which water molecules move across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration. This movement occurs passively, driven by the concentration gradient. Facilitated diffusion (B) involves the transport of specific molecules with the help of carrier proteins, not water. Phagocytosis (C) is a process where cells engulf solid particles, not water molecules. Exocytosis (D) is the process of releasing substances from a cell by fusion of vesicles with the cell membrane, not the transport of water across the membrane.

Correct Answer: D

Rationale: The correct answer is D because fires from flammable metals require specialized Class D fire extinguishers designed to extinguish these unique types of fires. Class A, B, and C fire extinguishers are not suitable for flammable metal fires as they are designed for different types of materials and fire classes. Class A extinguishers are for ordinary combustibles, Class B for flammable liquids, and Class C for electrical fires. Therefore, Class D fire extinguishers are specifically designed for flammable metal fires, making them the correct choice for this scenario.

Correct Answer: A

Rationale: Rationale for Correct Answer A (Diphtheria): 1. Thin yellow bacilli with dark brown grains on ends suggest Corynebacterium diphtheriae, characteristic of diphtheria. 2. Roman numeral five shape is typical of diphtheria bacilli. 3. Diphtheria causes sore throat and can spread in boarding schools. 4. Neisser staining method is used for diphtheria bacilli. Summary of Incorrect Choices: B: Scarlet fever is caused by Streptococcus pyogenes and presents with rash, not yellow bacilli. C: Listeriosis is caused by Listeria monocytogenes, not consistent with the described findings. D: Tonsillitis can be caused by various bacteria or viruses, but the specific characteristics described do not match.

Correct Answer: D

Rationale: The correct answer is D: Helicobacter pylori. Helicobacter pylori is a known bacterium associated with causing duodenal ulcers. The presence of Gram-negative curved bacteria in the biopsy along with a highly positive rapid urease test is characteristic of H. pylori infection. Vibrio cholerae causes cholera, not duodenal ulcers. Campylobacter fetus is associated with gastroenteritis, not duodenal ulcers. Acinetobacter baumannii is a nosocomial pathogen, not typically associated with duodenal ulcers. In summary, the unique combination of findings in this case points towards H. pylori as the most likely cause of the disease.