free microbiology test bank questions pdf -Nurselytic

Correct Answer: C

Rationale: The correct answer is C: Gram-positive rod-shaped bacteria. Listeria monocytogenes is a Gram-positive bacterium, as it retains the crystal violet stain during the Gram staining process. The bacteria are rod-shaped, not spherical.
Choice A is incorrect as Listeria monocytogenes is not Gram-negative.
Choice D is incorrect as Listeria monocytogenes does fall under the category of Gram-positive bacteria. The key is to remember the characteristics of Listeria monocytogenes, which are Gram-positive and rod-shaped.

Correct Answer: A

Rationale: The correct answer is A: viral DNA polymerase. This enzyme is essential for replicating the viral DNA during the herpesvirus life cycle. It catalyzes the synthesis of new DNA strands using the viral genomic template. Ribonucleotide reductase (
B) is involved in nucleotide synthesis, but not directly in DNA replication. Neuraminidase (
C) is an enzyme found in influenza viruses, not herpesviruses. Thymidine kinase (
D) is an enzyme that phosphorylates thymidine, but its role is more related to nucleotide metabolism rather than viral DNA replication.

Correct Answer: A

Rationale: The correct answer is A: Entamoeba histolytica. This protozoon is responsible for causing amoebic dysentery, which presents with bloody diarrhea. The "raspberry jelly" appearance of stool is due to the presence of mucosal lining and blood. The large mononuclear cells with absorbed red blood cells are characteristic of the histopathology of Entamoeba histolytica infection. Giardia lamblia (
B) causes watery diarrhea, not bloody stools. Campylobacter jejuni (
C) is a bacterial pathogen associated with gastroenteritis, but does not typically cause bloody diarrhea.
Toxoplasma gondii (
D) causes toxoplasmosis, a systemic infection with symptoms such as fever and lymphadenopathy, but not bloody diarrhea.

Correct Answer: B

Rationale: The correct answer is B: Neisseria gonorrhoeae. This bacterium is responsible for causing gonorrhea. Neisseria gonorrhoeae is a sexually transmitted bacterium that infects the mucous membranes of the reproductive tract. It is known for causing symptoms such as painful urination and discharge. Chlamydia trachomatis (choice
A) is another sexually transmitted bacterium but is not responsible for gonorrhea. Treponema pallidum (choice
C) causes syphilis, not gonorrhea. Escherichia coli (choice
D) is a common bacterium found in the gut and is not associated with causing gonorrhea.
Therefore, Neisseria gonorrhoeae is the correct answer for this question.

Correct Answer: A

Rationale: The correct answer is A: Clostridium perfringens. Clostridium perfringens is a gram-positive spore-forming bacillus commonly found in soil. It produces hemolysis on blood agar, as described in the question. Clostridium botulinum is also a gram-positive spore-forming bacillus, but it does not typically cause hemolysis. Staphylococcus aureus is a gram-positive cocci, not a bacillus. Pseudomonas aeruginosa is a gram-negative bacterium, not a gram-positive spore-forming bacillus.