microbiology chapter 13 test bank

Correct Answer: A

Rationale: The correct answer is A: Clostridium botulinum. Clostridium botulinum produces the botulinum toxin, which causes botulism. This bacteria thrives in anaerobic environments and can contaminate improperly canned foods. Clostridium tetani causes tetanus, not botulism. Staphylococcus aureus produces enterotoxins causing food poisoning, not botulism. Escherichia coli can cause food poisoning through various toxins, but not botulism. Therefore, the correct choice is Clostridium botulinum as it specifically produces the botulinum toxin responsible for botulism.

Correct Answer: C

Rationale: The correct answer is C: green monkeys. The Marburg virus was first identified in 1967 in Marburg and Frankfurt, Germany, after outbreaks in lab workers exposed to infected African green monkeys. These monkeys were imported from Uganda. The virus is believed to be originally endemic in certain species of African bats and is transmitted to humans through contact with infected animals. Choice A, laboratory rats, is incorrect as the virus did not originate from rats. Choice B, birds, and Choice D, wild turkeys, are also incorrect as there is no evidence linking these animals to the transmission of the Marburg virus.

Correct Answer: B

Rationale: The correct answer is B: Herpangina. Coxsackie Viruses are known to cause Herpangina, which is characterized by sore throat, fever, and painful blisters in the mouth and throat. This is because Coxsackie Viruses typically infect the throat and mouth mucosa. Hemorrhagic conjunctivitis (A) is commonly caused by Adenoviruses, not Coxsackie Viruses. Mumps (C) is caused by the Mumps virus, a completely different virus. Poliomyelitis (D) is caused by the Poliovirus, not Coxsackie Viruses. Therefore, the correct answer is B as it aligns with the known pathogenicity of Coxsackie Viruses.

Correct Answer: C

Rationale: The correct descending order of taxonomic categories is domain, kingdom, phylum, class, order, family, genus, species. This hierarchical classification system helps organize and categorize living organisms based on their shared characteristics and evolutionary relationships. Explanation: - Domain is the broadest category, representing the highest level of classification. - Kingdom further divides organisms into major groups based on similar characteristics. - Phylum, class, order, family, and genus successively narrow down the classification based on more specific shared characteristics. - Species is the most specific category, representing individual organisms capable of interbreeding. Summary of other choices: A: Incorrect as it has the incorrect order of phylum, kingdom, and division. B: Incorrect as it has the incorrect order of family and species. D: Incorrect as it has the incorrect order of domain, kingdom, and class.

Correct Answer: B

Rationale: The correct answer is B: Salmonella enteritidis. In this case, the presence of Gram-negative rods producing gas in the blood culture indicates a likelihood of Salmonella infection, as it is a common cause of severe abdominal pain, vomiting, and gas production. Salmonella enteritidis is a known pathogen that can cause gastroenteritis and systemic infections. Escherichia coli (choice A) can also cause similar symptoms, but it is less likely to produce gas in blood culture. Clostridium perfringens (choice C) typically causes food poisoning with rapid onset and less likely to be isolated from blood cultures. Campylobacter jejuni (choice D) is associated with gastroenteritis but is less likely to cause systemic infections with gas-producing Gram-negative rods in blood culture.