Is penicillin harmful to humans cells? Why or why not?
Penicillin is not harmful to human cells. Penicillin prevents the synthesis of peptidoglycan in the cell wall of bacterial microbes causing the cell to lyse. Because penicillin targets the synthesis process, only actively grown cells are affected by the antibiotics-and, because human cells do not contain peptidoglycan in their cell walls, penicillin has very little toxicity for host cells.