The skin is the first line of defense in preventing penetration by infectious agents. however, the skin can be bypassed. which of the following scenarios allows an infectious agent to enter the body without damaging the skin? a. a person is infected with malaria when a mosquito bite punctures his skin. b. a girl gets a staph infection when she falls and scrapes her knee. c. a boy is infected with rabies when a dog bites his leg. d. bacteria on food is ingested through the mouth.

Keeping in mind the life cycle of bacteriophages, consider the following problem: during the reproductive cycle of a temperate bacteriophage, the viral dna inserts into the bacterial chromosome where the resultant prophage behaves much like a trojan horse. it can remain quiescent, or it can become lytic and initiate a burst of progeny viruses. several operons maintain the prophage state by interacting with a repressor that keeps the lytic cycle in check. insults (ultraviolet light, for example) to the bacterial cell lead to a partial breakdown of the repressor, which in turn causes the production of enzymes involved in the lytic cycle. as stated in this simple form, would you consider this system of regulation to be operating under positive or negative control?

Each circled letter in the circuit diagram represents a meter that is used to measure a quantity in the circuit. which meters are ammeters

8. medical asepsis describes a condition that is sterile, or involving infection. sterile, or free from infection. contaminated, or involving infection. contaminated, or free from infection