ATI RN
mcgraw hill microbiology test bank Questions
Question 1 of 9
The most common congenital infection worldwide is due to:
Correct Answer: A
Rationale: The correct answer is A: CMV (Cytomegalovirus). CMV is the most common congenital infection worldwide due to its high prevalence and ability to be transmitted from mother to fetus during pregnancy. It can lead to serious complications such as hearing loss, developmental delays, and vision problems in newborns. Listeria monocytogenes (B) is a foodborne pathogen, not typically associated with congenital infections. Rubella Virus (C) can cause congenital rubella syndrome but is less common globally compared to CMV. Syphilis (D) can also be transmitted from mother to fetus, but its prevalence and impact on congenital infections are lower compared to CMV.
Question 2 of 9
All of the following are methods for food preservation except
Correct Answer: B
Rationale: The correct answer is B: Disinfection. Disinfection is not a method for food preservation but rather a process of destroying harmful microorganisms on surfaces. A: Pasteurization involves heating food to kill pathogens, preserving the food. C: Irradiation uses radiation to kill bacteria and parasites, extending shelf life. D: Ultrahigh-temperature pasteurization involves heating food at very high temperatures to extend shelf life. In summary, disinfection is not a method used to preserve food but rather to clean surfaces.
Question 3 of 9
The normal microflora is related to the defense in pathogens in
Correct Answer: C
Rationale: The normal microflora plays a crucial role in defending against pathogens in the skin and mucus. This is because the skin and mucus act as physical barriers and the normal microflora outcompetes potential pathogens, preventing their colonization. In contrast, the circulatory system (A), hepatobiliary tract (B), and CNS (D) are not typically colonized by normal microflora, so they do not directly contribute to defense against pathogens in those areas.
Question 4 of 9
4 days after a patient received a gunshot wound of the middle third of the thigh soft tissues his condition suddenly began deteriorating. There are complaints of bursting pain in the wound; pain increases during the last 12 hours. Edema of skin and hypodermic tissue quickly grows. Body temperature is 38,2oC, heart rate is 102/min. The wound edges gape, are dull in color; the muscles, viable as of day before, now protrude into the wound, look boiled, are dull in color, have dirty-grey coating and fall apart when being held with forceps. What infection has developed in the wound?
Correct Answer: A
Rationale: The correct answer is A: Anaerobic infection. The sudden deterioration, bursting pain, edema, foul appearance of wound, and presence of gas are indicative of gas gangrene caused by anaerobic bacteria like Clostridium perfringens. These bacteria thrive in low oxygen environments, such as deep wound tissues. The symptoms align with the classic presentation of gas gangrene, necessitating immediate surgical intervention. Choice B: Aerobic gram-negative, is incorrect because anaerobic bacteria, not aerobic gram-negative bacteria, are responsible for gas gangrene. Choice C: Putrid, is incorrect as it is a general term referring to foul-smelling decay and does not specify the type of infection. Choice D: Aerobic gram-positive, is incorrect as gas gangrene is typically caused by anaerobic bacteria, not aerobic gram-positive bacteria.
Question 5 of 9
Which bacteria are responsible for causing the disease known as 'whooping cough'?
Correct Answer: A
Rationale: The correct answer is A: Bordetella pertussis. Bordetella pertussis is the bacterium responsible for causing whooping cough, also known as pertussis. It produces toxins that damage the respiratory tract, leading to severe coughing fits. Haemophilus influenzae, Streptococcus pneumoniae, and Mycobacterium tuberculosis are not associated with whooping cough. Haemophilus influenzae can cause respiratory infections but not whooping cough. Streptococcus pneumoniae is known for causing pneumonia, and Mycobacterium tuberculosis causes tuberculosis, both different from whooping cough. Therefore, the correct answer is A as it is the specific bacterium linked to the disease in question.
Question 6 of 9
A patient with suspected liver abscess was admitted to the surgical department. The patient had been staying for a long time on business in one of African countries and fell repeatedly ill with acute gastrointestinal disorders. What protozoal disease may the patient be now ill with?
Correct Answer: A
Rationale: Rationale: The correct answer is Amebiasis (choice A) because the patient's symptoms of acute gastrointestinal disorders and prolonged stay in an African country suggest exposure to Entamoeba histolytica, the causative agent of amebiasis. This protozoal infection commonly occurs in tropical regions, including Africa. Trypanosomosis (choice B) is caused by Trypanosoma species transmitted by tsetse flies, primarily found in sub-Saharan Africa. Leishmaniasis (choice C) is transmitted by sandflies and presents with skin lesions or visceral involvement, not acute gastrointestinal symptoms. Malaria (choice D) is caused by Plasmodium parasites transmitted by mosquitoes and typically presents with fever, not acute gastrointestinal disorders. Therefore, choices B, C, and D are incorrect based on the patient's clinical presentation and travel history.
Question 7 of 9
Which one of all the clostridia that are associated with the disease myonecrosis/gas-gangrene can produce enterotoxin and could be responsible for the development of food intoxications:
Correct Answer: B
Rationale: The correct answer is B: Clostridium perfringens. This bacterium is associated with myonecrosis/gas gangrene and can produce enterotoxin causing food intoxication. Clostridium septicum (A) is associated with wound infections but not known for food intoxications. Clostridium histolyticum (C) is not typically associated with myonecrosis or food intoxications. Clostridium novyi (D) is known for causing black disease in sheep and cattle, not food intoxications.
Question 8 of 9
Sanitary assessment of a pond, where the children from a recreation summer camp take their swims, detected there oval cysts 50-60 micron in diameter, with 2 nuclei visible in their cytoplasm (macronucleus and micronucleus). What protozoa do these cysts belong to?
Correct Answer: D
Rationale: The correct answer is D: Lamblia. The cysts described match the characteristics of Giardia lamblia, a protozoan parasite. Giardia cysts are oval-shaped, 50-60 microns in diameter, and contain 2 nuclei (macronucleus and micronucleus). Giardia is commonly found in contaminated water sources and can cause gastrointestinal illness in humans. Incorrect choices: A: Toxoplasma - Toxoplasma gondii is a parasite that causes toxoplasmosis, transmitted through ingestion of contaminated food or water, but its cysts do not match the description given in the question. B: Amoeba - Amoebas are single-celled organisms, but they do not typically form cysts with visible nuclei as described. C: Balantidium - Balantidium coli is a ciliated protozoan that can cause dysentery in humans, but its cysts do not
Question 9 of 9
Bacterial transformation involves:
Correct Answer: B
Rationale: The correct answer is B: Uptake of naked DNA from the environment. Bacterial transformation is a process where bacteria take up free DNA from their surroundings and incorporate it into their own genome. This process is essential for genetic recombination and the acquisition of new traits. Plasmids are small DNA molecules that can be transferred between bacteria, but not necessarily through pili. Bacteriophages are viruses that infect bacteria and transfer their DNA, but this is not the primary mechanism of bacterial transformation. Binary fission is a method of bacterial reproduction, not related to the uptake of DNA.