ATI RN
microbiology chapter 1 test bank Questions
Question 1 of 9
All of the following are components of the gastrointestinal tract except the:
Correct Answer: A
Rationale: The correct answer is A: spleen. The spleen is not a component of the gastrointestinal tract; it is part of the lymphatic system. The pharynx, esophagus, and stomach are all part of the gastrointestinal tract responsible for digestion and absorption of food. The spleen's main functions include filtering blood, storing blood cells, and supporting the immune system, making it unrelated to the digestive process.
Question 2 of 9
Soil microflora often includes the representatives of pathogenic microorganisms. Specify the diseases, whose causative agents may say viable in the soil for a long time:
Correct Answer: B
Rationale: The correct answer is B: Tuberculosis and mycobacterioses. Mycobacterium tuberculosis, the causative agent of tuberculosis, and other mycobacteria can survive in the soil for extended periods. Here's the rationale: 1. Mycobacteria have a waxy cell wall that provides resistance to harsh environmental conditions. 2. The slow growth rate of mycobacteria allows them to persist in the soil for long periods. 3. Tuberculosis and mycobacterioses are known to be transmitted through environmental exposure, including soil. 4. Colibacillosis and cholera (Choice C) are caused by enteric bacteria that do not survive well in soil. 5. Leptospirosis and plague (Choice D) are bacterial diseases transmitted through animal hosts and are not known to be soil-borne.
Question 3 of 9
A patient with dysentery had a stool sample that was cultured on Endo agar, resulting in colorless colonies. The bacteria were Gram-negative rods. What is the most likely causative agent?
Correct Answer: A
Rationale: Rationale: 1. Endo agar inhibits the growth of Gram-positive bacteria. 2. Colorless colonies on Endo agar indicate lactose non-fermenting bacteria. 3. Shigella dysenteriae is a lactose non-fermenting, Gram-negative rod, causing dysentery. 4. Salmonella typhi, Escherichia coli, and Proteus vulgaris are lactose fermenters, so they would produce pink colonies on Endo agar. Therefore, the most likely causative agent is Shigella dysenteriae.
Question 4 of 9
A puncture sample taken from the lymph node of a patient with preliminary diagnosis of protozoan disease has been investigated. The preparation was processed with Giemsa stain and the following was detected: crescent-shaped bodies with pointed tips, blue cytoplasm and red nuclei. What protozoa have been detected in the preparation?
Correct Answer: D
Rationale: The correct answer is D: Viscerotropic Leishmania. The presence of crescent-shaped bodies with pointed tips, blue cytoplasm, and red nuclei is characteristic of Leishmania species. Viscerotropic Leishmania causes visceral leishmaniasis, also known as kala-azar, which affects the internal organs. Toxoplasma typically presents as tachyzoites, not crescent-shaped bodies. Plasmodium malariae is a malaria parasite with different morphology. Dermatotropic Leishmania causes cutaneous leishmaniasis, not the visceral form indicated by the morphology described in the question.
Question 5 of 9
All of the following are components of the gastrointestinal tract except the:
Correct Answer: A
Rationale: The correct answer is A: spleen. The spleen is not a component of the gastrointestinal tract; it is part of the lymphatic system. The pharynx, esophagus, and stomach are all part of the gastrointestinal tract responsible for digestion and absorption of food. The spleen's main functions include filtering blood, storing blood cells, and supporting the immune system, making it unrelated to the digestive process.
Question 6 of 9
The most severe bacillary infections are caused by:
Correct Answer: D
Rationale: The correct answer is D: Shigella dysenteriae I. This bacterium is known to produce Shiga toxin, which is responsible for the most severe bacillary infections. The toxin can cause bloody diarrhea and potentially life-threatening complications like hemolytic uremic syndrome. Shigella boydii, flexneri, and sonnei, while also causing bacillary dysentery, do not produce the same level of severity as Shigella dysenteriae I due to the absence of Shiga toxin.
Question 7 of 9
The laboratory for especially dangerous infections conducts microscopic examination of pathological material from a patient with suspected plague. The sample was stained by Burri-Gins technique. What property of the causative agent can be identified by this technique?
Correct Answer: A
Rationale: The Burri-Gins staining technique is used to identify capsule formation in bacteria. Capsules are protective layers around bacteria that can be visualized using this staining method. Capsules are important virulence factors for pathogens like Yersinia pestis, the causative agent of plague. This technique helps in differentiating encapsulated bacteria from non-encapsulated ones. Spore formation (B), acid resistance (C), and alkali resistance (D) are not properties that can be identified using the Burri-Gins technique, making them incorrect choices.
Question 8 of 9
Which of the following has a fecal-oral route of transmission
Correct Answer: C
Rationale: The correct answer is C: ECHO virus infection. ECHO virus is transmitted via the fecal-oral route, meaning the virus is passed from feces to the mouth. This transmission occurs through contaminated food, water, or surfaces. Relapsed fever and spotted fever are generally transmitted by arthropod vectors like ticks. Pertussis, also known as whooping cough, spreads through respiratory droplets. Therefore, the fecal-oral route is not applicable to these diseases.
Question 9 of 9
During the regular sanitary epidemiological inspection of a pharmacy, the bacteriological analysis of air was performed. The air was found to have bacilli, yeast fungi, hemolytic streptococci, micrococci. Which of the detected microorganisms indicate the direct epidemic danger?
Correct Answer: A
Rationale: The correct answer is A: Haemolytic streptococci. Hemolytic streptococci are known to cause serious infections in humans, including strep throat and skin infections. These bacteria have the potential to spread rapidly and cause epidemics. Bacilli are a broad category of bacteria and not all are necessarily harmful. Micrococci are commonly found on human skin and are generally harmless. Yeast fungi are also commonly found in the environment and are not typically associated with causing epidemics. Therefore, the presence of hemolytic streptococci in the air of a pharmacy indicates a direct epidemic danger due to their pathogenic nature and potential to cause widespread infections.