Toxigenic microbes produce _______. A high ID₅₀ would suggest _______, and a low LD₅₀ would suggest _______.

Pili, fimbriae, and sialic acid binding factors are examples of ________, which are virulence factors that allow pathogens to ________ host tissues––an essential early step in pathogenesis. In contrast, flagella, collagenases, and coagulases tend to act as ________, which help pathogens spread deeper into host tissues.

A pathogen that makes endotoxin, enters through the fecal–oral route, and lacks a nucleus is most likely a

a. Virus.

b. Gram-positive bacterium.

c. Gram-negative bacterium.

d. Protozoan pathogen.

e. There is not enough information to answer this question.

Select the false statement about normal microbiota.

a. They compete with pathogens.

b. They do not include potential pathogens.

c. They make vitamins for the host.

d. They train the immune system.

e. A disruption in their balance can lead to disease.

What is a reservoir, and why can C. difficile use a fomite as an effective environmental reservoir?

Which of the following is false regarding biofilms?

a. They tend to consist of one species of microbe.

b. They are platforms on which pathogens may adhere.

c. They form on indwelling devices.

d. They may harbor pathogens.

e. They can form on natural and manufactured surfaces.

Complete the table: