Chapter 20

Question 1

action of antimicrobial drugs

Answer 1

inhibition of cell wall synthesis
inhibition of protein synthesis
inhibition of nucleic acid synthesis
injury to plasma membrane
inhibition of essential metabolite synthesis

Question 2

inhibition of cell wall synthesis

Answer 2

penicillins prevent the synthesis of peptidoglycan
very little toxicity for the host, human cells don’t have peptidoglycan

Question 3

inhibition of protein synthesis

Answer 3

Target bacterial 70S ribosomes (eukaryotic cells have 80S ribosomes except for mitochondria)

Question 4

injury to plasma membrane

Answer 4

polypeptide antibiotics change membrane permeability and loss of important metabolites
anti fungal drugs combine with membrane sterols

Question 5

inhibition of nucleic acid synthesis

Answer 5

interfere with DNA replication and transcription

Question 6

inhibition of essential metabolite synthesis

Answer 6

antimetabolites compete with normal substrate for an enzyme
Sulfanilamide competes with para-aminobenzoic acid (PABA) stopping the synthesis of folic acid