ATI RN
foundations in microbiology test bank Questions
Question 1 of 5
Ionizing radiation involves all of the following except
Correct Answer: A
Rationale: Ionizing radiation has enough energy to remove tightly bound electrons from atoms, creating charged particles (ions). UV light does not have enough energy to ionize atoms, making choice A the correct answer. Gamma rays, electron beams, and X-rays all have sufficient energy to cause ionization. Gamma rays are very high-energy electromagnetic radiation, electron beams are streams of high-energy electrons, and X-rays are high-energy electromagnetic radiation as well.
Question 2 of 5
Which of the following transport mechanisms transports water across the plasma membrane?
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.
Question 3 of 5
During sanitary and bacteriological testing of water with the membrane filter technique there were revealed two red colonies on a membrane filter (Endo agar) through which 500 ml of water was filtred. Calculate the coli index and coli titer of the analyzed water:
Correct Answer: C
Rationale: The correct answer is C (coli index of 250 and coli titer of 4). The coli index is calculated by multiplying the number of colonies by the reciprocal of the volume filtered, which gives 2 colonies x (1/0.5 L) = 4. The coli titer is obtained by dividing the volume filtered by the number of colonies, which gives 0.5 L / 2 colonies = 0.25 L or 250 ml. This indicates the concentration of coliform bacteria in the water sample.
Choice A (4 and 250) is incorrect because it has the correct coli index but the values are reversed for coli index and coli titer.
Choice B (2 and 500) is incorrect as it provides the correct coli titer value but the values are reversed for coli index and coli titer.
Choice D (500 and 2) is incorrect because it reverses the values for both coli index and coli titer.
Question 4 of 5
Which of the following viruses could be reactivated under immunosuppressive therapy?
Correct Answer: D
Rationale: The correct answer is D, "None of the above," because viruses like Parotitidis (mumps), Rubella, and Influenza A are not typically associated with reactivation under immunosuppressive therapy. Reactivation is more commonly seen in latent viruses like herpesviruses (e.g., herpes simplex, varicella-zoster), cytomegalovirus, and Epstein-Barr virus. These viruses can remain dormant in the body and reactivate when the immune system is compromised.
Therefore, the correct answer is D, as the viruses mentioned in choices A, B, and C do not fit the criteria for reactivation under immunosuppressive therapy.
Question 5 of 5
Which of the following stains is the most widely used differential stain in hematology laboratories?
Correct Answer: D
Rationale: The correct answer is D: Kinyoun stain. This stain is the most widely used differential stain in hematology labs because it is specifically designed for acid-fast bacteria like Mycobacterium tuberculosis. It differentiates these bacteria from others based on their cell wall composition. Carbolfuchsin stain (
A) is used for acid-fast bacteria in microbiology. Wright's stain (
B) is used for blood cell morphology. Ziehl-Neelsen stain (
C) is also used for acid-fast bacteria but is less commonly used compared to Kinyoun stain in hematology labs.