microbiology basic and clinical principles test bank

Correct Answer: B

Rationale: The correct answer is B: Neisseria meningitidis. This is because Neisseria meningitidis is a Gram-negative diplococci that is oxidase-positive and fermentative. Neisseria gonorrhoeae (choice A) is also a Gram-negative diplococci but is not fermentative. Haemophilus influenzae (choice C) is not a diplococci and Moraxella catarrhalis (choice D) is oxidase-negative. Thus, Neisseria meningitidis fits all the criteria provided in the question, making it the most likely causative agent for the sepsis in this patient.

Correct Answer: C

Rationale: The correct answer is C: cytoplasmic membrane. The cytoplasmic membrane is the fluidlike portion of a cell that separates the cell's contents from the external environment. It regulates the passage of substances in and out of the cell, maintains cell shape, and provides protection. Rationale: 1. Cytosol (choice A) is the liquid component of the cytoplasm where organelles are suspended, not the fluidlike portion of the cell. 2. Nucleoplasm (choice B) refers to the liquid component of the nucleus, not the entire cell. 3. Inclusion (choice D) refers to non-living substances within the cell that are not considered the fluidlike portion. Summary: The cytoplasmic membrane is the correct answer as it encompasses the entire cell and is responsible for maintaining cell integrity and regulating transport. Choices A, B, and D are incorrect as they do not represent the fluidlike portion of the cell.

Correct Answer: A

Rationale: The correct answer is A: Robert Hooke. Hooke published Micrographia in 1665, showcasing detailed illustrations of insects, sponges, and plant cells under the microscope. Hooke's work was groundbreaking in advancing the field of microscopy. Van Leeuwenhoek is known for discovering microorganisms but did not publish Micrographia. Janssen and Needham were not associated with Micrographia. Therefore, A is the correct answer.

Correct Answer: A

Rationale: The correct answer is A: Trichomonas vaginalis. Trichomonas vaginalis is a protozoan parasite that causes trichomoniasis, a sexually transmitted infection characterized by inflammation of urogenital tracts. The description of big unicellular pyriform organisms with a sharp spike on the back end of their bodies, big nucleus, and undulating membrane matches the morphology of Trichomonas vaginalis. Trichomonas hominis and Trichomonas buccalis are different species that do not cause urogenital infections. Trypanosoma gambiense is a protozoan parasite causing African trypanosomiasis and does not match the described morphology or symptoms.

Correct Answer: A

Rationale: The correct answer is A: Neisseria meningitidis. Step 1: Gram-negative diplococci - characteristic of Neisseria species. Step 2: Oxidase-positive - Neisseria species are oxidase-positive. Step 3: Fermentative - Neisseria meningitidis is a fermentative bacterium. Therefore, Neisseria meningitidis is the most likely causative agent. Summary: - B: Neisseria gonorrhoeae is also a Neisseria species but is not fermentative. - C: Moraxella catarrhalis is oxidase-positive but not fermentative. - D: Haemophilus influenzae is not a Neisseria species and is not typically fermentative.