penicillin was considered a \miracle drug\ for all of the following reasons except\nit does not affect…
penicillin was considered a \miracle drug\ for all of the following reasons except\nit does not affect eukaryotic cells\nin inhibits gram - positive cell wall synthesis\nit was the first antibiotic\nit has selective toxicity\nquestion 12 (1 point)\nwhich of the following terms refers to the ability of an antimicrobial drug to harm\nthe target microbe without harming the host?\nselective toxicity\nspectrum of activity\ntherapeutic level\nmode of action
Answer
Brief Explanations:
- For the first question: Penicillin is a beta - lactam antibiotic. It inhibits the synthesis of the peptidoglycan layer in the cell wall of gram - positive bacteria. Since human cells (eukaryotic) do not have a peptidoglycan cell wall, it does not affect eukaryotic cells. Selective toxicity means that the drug harms the microbe but not the host. However, the fact that it was the first antibiotic is not the reason it is called a "miracle drug". The key properties that make it a "miracle drug" are related to its mechanism of action (inhibiting cell - wall synthesis in bacteria, not affecting eukaryotes) and its selective toxicity.
- For the second question: Selective toxicity is defined as the ability of an antimicrobial drug to harm the target microbe without harming the host. The spectrum of activity refers to the range of microbes (e.g., gram - positive, gram - negative, etc.) that a drug can act against. Therapeutic level is the concentration of the drug in the body that is effective for treatment. Mode of action is how the drug acts on the microbe (e.g., inhibiting protein synthesis, cell - wall synthesis, etc.).
Answer:
- First question: it was the first antibiotic
- Second question: selective toxicity