Question

question 19 (2.5 points)
infections that are spread by fleas and ticks are caused by ____.
rickettsia
fomites
protozoa
bacteria
question 20 (2.5 points)
which flora occur in periods of limited duration?
transient
virulence
resident
asepsis

Explanation:

Question 19

Rickettsia are bacteria - like organisms that are often spread by arthropod vectors such as fleas and ticks. Fomites are inanimate objects that can carry pathogens, not the cause of infections spread by fleas/ticks. Protozoa are single - celled eukaryotes and not typically spread by fleas/ticks in this context. Bacteria is a broad term, and rickettsia is the specific agent spread by fleas and ticks here.

Transient flora are microorganisms that are present on the body for a short, limited period of time. Virulence refers to the ability of a pathogen to cause disease, not a type of flora. Resident flora are the normal, long - term flora of the body. Asepsis is the practice of preventing infection, not a type of flora.

Answer:

A. rickettsia

Question 20