mastering microbiology test bank

Correct Answer: B

Rationale: The Gram stain differentiates bacteria based on cell wall structure. It classifies bacteria into Gram-positive (purple) and Gram-negative (pink) based on the presence of peptidoglycan in the cell wall. This method helps in identifying the bacterial species and determining appropriate treatment. Option A (Cell shape) is incorrect because the Gram stain focuses on cell wall composition, not cell shape. Option C (Flagella composition) is incorrect as the Gram stain does not assess flagella. Option D (Nutrient requirements) is incorrect as it does not relate to the purpose of the Gram stain.

Correct Answer: C

Rationale: Rationale for choice C (Adenovirus) being correct: 1. Adenovirus is a common cause of acute hemorrhagic cystitis. 2. Adenovirus infects the bladder epithelium, leading to inflammation and bleeding. 3. Symptoms include hematuria and bladder pain. 4. Diagnosis is confirmed through viral culture or PCR testing. Summary of why other choices are incorrect: A: Parvovirus B19 - More commonly associated with erythema infectiosum (fifth disease) and aplastic anemia. B: CMV - Known to cause congenital infections, mononucleosis, and retinitis, not typically associated with hemorrhagic cystitis. D: Herpesvirus type 2 - Commonly causes genital herpes, but not typically associated with acute hemorrhagic cystitis.

Correct Answer: A

Rationale: The correct answer is A: Tryptic soy agar is a general-purpose medium suitable for cultivating a wide range of microorganisms. It provides essential nutrients for growth without inhibiting specific types of bacteria. Blood agar (B), Mannitol salt agar (C), and MacConkey agar (D) are selective or differential media designed to promote the growth of specific types of bacteria or differentiate between different bacterial species. Therefore, they are not considered general-purpose mediums.

Correct Answer: C

Rationale: The correct answer is C: Transcription. Transcription is the process of synthesizing RNA from a DNA template. During transcription, RNA polymerase binds to the DNA and produces a complementary RNA strand. This process is essential for gene expression. Explanation for why other choices are incorrect: A: Transposition involves the movement of genetic elements within a genome, not the production of RNA from DNA. B: Translation is the process of synthesizing proteins from mRNA, not the production of RNA from DNA. D: RNA splicing is the process of removing introns and joining exons in pre-mRNA to produce mature mRNA, not the initial production of RNA from DNA.

Correct Answer: C

Rationale: The Baltimore classification system categorizes viruses based on their genome type and replication strategy. It divides viruses into seven groups: Group I (dsDNA), Group II (ssDNA), Group III (dsRNA), Group IV (ssRNA(+)), Group V (ssRNA(-)), Group VI (ssRNA-RT), and Group VII (dsDNA-RT). Each group represents a distinct viral genome and replication method. Therefore, the correct answer is C. The other choices are incorrect because the Baltimore classification system specifically identifies viruses into seven groups, not four, five, or nine.