Given that both human cells and pathogens synthesize proteins at ribosomal sites, how can antimicrobial agents that target this process be safe to use in humans?

What specific test for antimicrobial efficacy is shown? What does this test measure? Draw an oval to predict the size and shape of the zone of inhibition if the drug concentration on the strip were increased twofold.

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What characteristics would an ideal chemotherapeutic agent have? Which drug has these qualities?

Contrast narrow-spectrum and broad-spectrum drugs. Which are more effective?

Why is the fact that drug Z destroys the NAM portions of a cell’s wall structure an important factor in considering the drug for chemotherapy?

Label each of the accompanying figures to indicate the class of drug that is stopping polypeptide translation.

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a. ________________ b. _________________

block initiation. change 30S subunit.

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c. ________________ d. _________________

block ribosome attachment inhibits peptide bonding

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e. ________________ g. _________________

f. ________________ h. _________________

block ribosome movement block tRNA docking

Which of the following chemical agents is a gas? 

You and your classmates are trying to determine how a disinfectant might kill cells. You observe that when you spill the disinfectant in a tube of reduced litmus milk, the litmus turns blue again. You suggest to your classmates that

a. the disinfectant might inhibit cell wall synthesis.

b. the disinfectant might oxidize molecules.

c. the disinfectant might inhibit protein synthesis.

d. the disinfectant might denature proteins.

e. the disinfectant might damage DNA.

DRAW IT Show where the following antibiotics work: ciprofloxacin, tetracycline, streptomycin, vancomycin, polymyxin B, sulfanilamide, rifampin, erythromycin.

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