Q: Which of the following equations best represents the minimum infectious dose (ID) for a pathogen?

$$ID = \text{minimum number of microbes required for infection to proceed}$$

Question 1

Which of the following best describes a true pathogen?

Accepted Answer

An organism that causes disease in hosts with normal defenses.

Question 2

A patient develops a urinary tract infection after a surgical procedure in a hospital. Which term best describes this infection?

Accepted Answer

Nosocomial infection

Question 3

Which of the following is a virulence factor that allows bacteria to evade phagocytosis?

Accepted Answer

Slime layer or capsule (glycocalyx)

Question 4

Which biosafety level (BSL) requires the use of full-body, air-supplied suits and is used for handling microbes with little or no available treatment or vaccine?

Accepted Answer

BSL-4

Question 5

Which portal of entry is most likely for a pathogen transmitted by sexual contact?

Accepted Answer

Urogenital tract

Question 6

Which of the following statements about exotoxins is TRUE?

Accepted Answer

Exotoxins are proteins, actively secreted, and highly antigenic.

Question 7

A patient is infected with Vibrio cholerae after drinking contaminated water. Which concept explains why a large infectious dose is required for this organism?

Accepted Answer

The organism is easily destroyed by stomach acid.

Question 8

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

Accepted Answer

A fly that carries bacteria on its legs but is not infected

Question 9

Which stage of clinical infection is characterized by the most intense signs and symptoms?

Accepted Answer

Acute stage

Question 10

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

Accepted Answer

Fever measured by thermometer

Question 11

A patient recovers from a viral infection but later develops permanent heart damage. What is this long-term effect called?

Accepted Answer

Sequelae

Question 12

Which of the following is NOT a universal precaution recommended for healthcare workers?

Accepted Answer

Recapping needles after use

Question 13

Which of the following is a characteristic of endotoxins?

Accepted Answer

Heat stable and usually induce fever

Question 14

Which of the following equations best represents the minimum infectious dose (ID) for a pathogen?

Accepted Answer

$$ID = 	ext{minimum number of microbes required for infection to proceed}$$

Question 15

Which of the following is an example of a zoonosis?

Accepted Answer

Rabies transmitted from a raccoon to a human

Question 16

Which of the following is a function of bacterial exoenzymes?

Accepted Answer

Breaking down host defenses such as hyaluronic acid and mucus

Question 17

A patient is infected with a bacterium that produces protein A. What is the effect of protein A on the immune response?

Accepted Answer

Protein A binds the Fc portion of antibodies, interfering with phagocytosis and complement activation.

Question 18

Which of the following best describes a superinfection?

Accepted Answer

An outgrowth of pathogenic microbes when normal flora are suppressed.

Question 19

Which of the following is a real-life example of indirect transmission of a communicable disease?

Accepted Answer

A person acquiring hepatitis A from contaminated food

Question 20

Which of the following best describes antigenic variation as a microbial strategy?

Accepted Answer

The microbe changes its surface antigens to evade immune detection.

Microbial Pathogenesis: Mechanisms and Clinical Implications

Study Guide - Practice Questions

Study Guide - Flashcards