Question 1

Which of the following best describes the relationship between humans and the bacteria in the human colon?

Accepted Answer

Mutualism

Question 2

A patient develops a urinary tract infection (UTI) caused by Escherichia coli, which is normally found in the colon. This is an example of:

Accepted Answer

A normal microbiota becoming an opportunistic pathogen

Question 3

Which of the following is NOT a step in Koch’s postulates?

Accepted Answer

The agent must be shown to be present in all healthy individuals.

Question 4

Which of the following is a correct description of endotoxins?

Accepted Answer

They are lipid A components of the outer membrane of Gram-negative bacteria.

Question 5

A disease that is naturally transmitted from animals to humans is called:

Accepted Answer

A zoonosis

Question 6

Which of the following is an example of a parenteral route of infection?

Accepted Answer

Stepping on a nail

Question 7

Which of the following is a function of bacterial adhesins?

Accepted Answer

They enable bacteria to attach to specific host cell receptors.

Question 8

Which of the following is a sign, not a symptom, of disease?

Accepted Answer

Fever

Question 9

Which of the following best describes the role of hyaluronidase and collagenase in bacterial infection?

Accepted Answer

They break down host connective tissues, facilitating bacterial invasion.

Question 10

Which of the following is true about the lagging strand during DNA replication?

Accepted Answer

It is synthesized in short fragments called Okazaki fragments.

Question 11

Which of the following is NOT a product of transcription?

Accepted Answer

A new strand of DNA

Question 12

Which of the following statements about translation is correct?

Accepted Answer

It involves decoding mRNA codons into a sequence of amino acids.

Question 13

Which of the following is an example of a biological vector?

Accepted Answer

A mosquito transmitting Plasmodium spp. (malaria)

Question 14

Which of the following best describes the difference between incidence and prevalence?

Accepted Answer

Incidence is the number of new cases in a given time period, while prevalence is the total number of cases at a given time.

Question 15

Which of the following is a communicable disease?

Accepted Answer

Influenza

Question 16

Which of the following is a correct statement about the genetic code?

Accepted Answer

It is the set of rules that determines how a nucleotide sequence is converted into the amino acid sequence of a protein.

Question 17

Which of the following is a plausible outcome if a patient’s immune system is suppressed?

Accepted Answer

Normal microbiota may become opportunistic pathogens.

Question 18

Which of the following is a function of bacterial capsules as a virulence factor?

Accepted Answer

They inhibit phagocytosis by host immune cells.

Question 19

Which of the following is true about exotoxins?

Accepted Answer

They are secreted proteins that can have specific effects on host cells.

Question 20

Which of the following best describes a focal infection?

Accepted Answer

An infection that serves as a source of pathogens for infections at other sites in the body

Microbial Infection, Disease, and Genetics: Core Concepts and Mechanisms

Study Guide - Practice Questions