Question 1

Which of the following best describes the relationship between Mycobacterium tuberculosis and the human lung?

Accepted Answer

Parasitism, because the bacterium benefits while harming the host.

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 for proving a microbe causes a specific disease?

Accepted Answer

The agent must be shown to be resistant to all antibiotics.

Question 4

Which of the following is a correct description of endotoxins?

Accepted Answer

They are lipid A components of the lipopolysaccharide layer in Gram-negative bacteria.

Question 5

A disease that is naturally transmitted from animals to humans, such as rabies, 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 statements about DNA replication is FALSE?

Accepted Answer

DNA replication proceeds in only one direction around the bacterial chromosome.

Question 8

Which of the following is NOT a product of transcription?

Accepted Answer

A new strand of DNA

Question 9

Which of the following best describes a focal infection?

Accepted Answer

It serves as a source of pathogens for infections at other sites in the body.

Question 10

Which of the following is a function of bacterial adhesins?

Accepted Answer

They bind to specific receptors on host cells, facilitating attachment.

Question 11

Which of the following is an example of indirect contact transmission?

Accepted Answer

Using a contaminated needle

Question 12

Which of the following best describes the genetic code?

Accepted Answer

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

Question 13

Which of the following is a characteristic of exotoxins?

Accepted Answer

They are proteins secreted by bacteria that can cause specific effects in the host.

Question 14

Which of the following is NOT a virulence factor?

Accepted Answer

Antibiotic resistance

Question 15

Which of the following is true about mechanical vectors?

Accepted Answer

They passively carry pathogens to new hosts.

Question 16

Which of the following is an example of a communicable disease?

Accepted Answer

Influenza

Question 17

Which of the following is the correct definition of a gene?

Accepted Answer

A sequence of nucleotides in DNA that codes for a functional product.

Question 18

Which of the following is NOT a portal of entry for pathogens?

Accepted Answer

Liver

Question 19

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

Accepted Answer

Fever

Question 20

Which of the following best describes the process of translation?

Accepted Answer

The decoding of mRNA into a sequence of amino acids to form a protein.

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

Study Guide - Practice Questions