Lab 19: Antibiotic susceptibility (Kirby-Bauer Method)

Question 1

define antibiotics

Answer 1

natural, semisynthetic, and synthetic chemicals that inhibit the growth of other microorganisms

Question 2

penicilin’s mode of action is to..

Answer 2

inhibit cell wall synthesis

Question 3

cephalosporins mode of action is to..

Answer 3

inhibit cell wall synthesis

Question 4

nalidixic acid mode of action is to..

Answer 4

inhibit nucleic acid synthesis

Question 5

polymyxin B mode of action is to..

Answer 5

disrupt the cytoplasmic membrane

Question 6

erythromycin’s mode of action is to..

Answer 6

inhibit protein synthesis

Question 7

tobramycin’s mode of action is to..

Answer 7

inhibit protein synthesis

Question 8

chloramphenicol’s mode of action is to..

Answer 8

inhibit protein synthesis

Question 9

SxT’s mode of action is to…

Answer 9

inhibit the metabolic pathways

Question 10

why are zones of inhibition compared to a standard table to determine an organism’s sensitivity?

Answer 10

b/c antibiotics are used internally. Accounts for digestion, absorption, and excretion of the antibody in humans/ animals.

Question 11

why do the filter paper disks contain standardized concentrations of antimicrobials?

Answer 11

to ensure method remains reliable by providing a general baseline of antibiotics

Question 12

why do resistant strains of bacteria appear in hospitals and nursing homes?

Answer 12

b/c bacteria are constantly exposed the antibiotics

Question 13

what media is used for the Kirby-Bauer method?

Answer 13

MHA