ATI RN
foundations in microbiology test bank Questions
Question 1 of 9
The enzyme used by bacteria to break down hydrogen peroxide is:
Correct Answer: B
Rationale: The correct answer is B: Catalase. Catalase is the enzyme responsible for breaking down hydrogen peroxide into water and oxygen. This process helps protect the bacteria from oxidative damage caused by hydrogen peroxide. Amylase (A), Lipase (C), and Protease (D) are enzymes that are not involved in breaking down hydrogen peroxide. Amylase is involved in breaking down starch, Lipase breaks down lipids, and Protease breaks down proteins. Therefore, they are not the correct enzymes for the given question.
Question 2 of 9
In which of the following GIT infections, the bacteria adhere to the intestine wall and produce toxins
Correct Answer: C
Rationale: The correct answer is C: enterotoxigenic E. Coli (ETEC). ETEC adheres to the intestine wall and produces toxins, leading to symptoms like diarrhea. Shigella spp. invade intestinal cells, Salmonella spp. cause inflammation, and Helicobacter pylori infects the stomach lining. This makes them incorrect choices for bacteria adhering to the intestine wall and producing toxins.
Question 3 of 9
Fires from flammable metals require type __________ fire extinguishers.
Correct Answer: D
Rationale: The correct answer is D because fires from flammable metals require specialized Class D fire extinguishers designed to extinguish these unique types of fires. Class A, B, and C fire extinguishers are not suitable for flammable metal fires as they are designed for different types of materials and fire classes. Class A extinguishers are for ordinary combustibles, Class B for flammable liquids, and Class C for electrical fires. Therefore, Class D fire extinguishers are specifically designed for flammable metal fires, making them the correct choice for this scenario.
Question 4 of 9
For family Rhabdoviridae is true that:
Correct Answer: A
Rationale: The correct answer is A: They are enveloped viruses. Rhabdoviridae family consists of enveloped viruses, which means they have a lipid envelope surrounding their protein coat. This envelope helps the virus in infecting host cells and evading the immune system. The other choices are incorrect because B: They cause plague is not true as Rhabdoviridae family typically causes diseases like rabies in mammals. C: They have spherical shape is incorrect as rhabdoviruses have a bullet-shaped structure. D: They infect only humans is also incorrect as Rhabdoviridae viruses can infect a wide range of hosts beyond just humans.
Question 5 of 9
There are several cases of children from boarding school suffering from sore throat. Microscopy of tonsil smears stained according Neisser method has revealed thin yellow bacilli with dark brown grains on their ends placed in the shape of Roman numeral five. What infection can be suspected in this case?
Correct Answer: A
Rationale: Rationale for Correct Answer A (Diphtheria): 1. Thin yellow bacilli with dark brown grains on ends suggest Corynebacterium diphtheriae, characteristic of diphtheria. 2. Roman numeral five shape is typical of diphtheria bacilli. 3. Diphtheria causes sore throat and can spread in boarding schools. 4. Neisser staining method is used for diphtheria bacilli. Summary of Incorrect Choices: B: Scarlet fever is caused by Streptococcus pyogenes and presents with rash, not yellow bacilli. C: Listeriosis is caused by Listeria monocytogenes, not consistent with the described findings. D: Tonsillitis can be caused by various bacteria or viruses, but the specific characteristics described do not match.
Question 6 of 9
All of the following are beta-lactam antibiotics except
Correct Answer: D
Rationale: The correct answer is D, Vancomycin, because it is not a beta-lactam antibiotic. Beta-lactam antibiotics contain a beta-lactam ring in their molecular structure, which Vancomycin lacks. Benzylpenicillin, Cephalosporin, and Monobactam all contain the beta-lactam ring, making them beta-lactam antibiotics. Vancomycin belongs to a different class of antibiotics called glycopeptides.
Question 7 of 9
Which of the following bacteria produce toxins that can lead to foodborne illnesses?
Correct Answer: D
Rationale: The correct answer is D. Clostridium botulinum produces botulinum toxin, Salmonella enterica produces salmonella toxin, and certain strains of Escherichia coli produce toxins like shiga toxin. These toxins can cause severe foodborne illnesses. Therefore, all of the above bacteria can produce toxins that lead to foodborne illnesses. Choices A, B, and C alone are incorrect because each of these bacteria individually can produce toxins that lead to foodborne illnesses.
Question 8 of 9
In humans, the embryonic phase of development extends from fertilization to the end of week __________, after which the developing infant is called a fetus.
Correct Answer: C
Rationale: The correct answer is C: 8. The embryonic phase in humans lasts until the end of week 8. During this time, the major organs and structures of the body begin to form. After week 8, the developing organism is referred to as a fetus. Choice A (2) is too early for this transition to occur, Choice B (6) is also premature, and Choice D (12) is too late as the embryonic phase ends before week 12. Therefore, the correct answer is C (8) as it accurately reflects the timeline of embryonic development in humans.
Question 9 of 9
After the transfer of the F plasmid from the donor to the recipient cell..
Correct Answer: D
Rationale: After the transfer of the F plasmid from the donor to the recipient cell, the correct answer is D. This is because the F plasmid carries genes for conjugation, allowing the recipient cell to become F+ (containing the F plasmid). The donor cell remains F. Choice A is incorrect as the outcome can be predicted based on the transfer of the F plasmid. Choice B is incorrect because the donor cell does not become F after transferring the F plasmid. Choice C is incorrect as only the recipient cell becomes F+, not both cells.