A Level Biology Practice Exam

What is penicillin primarily used for?

1. As a pain reliever

2. As a safe antibiotic

3. As an antifungal medication

4. As a vaccine component

The correct answer is: As a safe antibiotic

Penicillin is primarily used as an antibiotic, which means it is effective in treating bacterial infections by inhibiting the growth of bacteria. It works by interfering with the formation of the bacteria's cell wall, ultimately leading to cell lysis and death. This makes penicillin a critical medication in medicine for treating a wide range of infections caused by susceptible bacteria. Other options mention uses that do not align with penicillin’s primary function. Pain relievers are not antibiotics; instead, they may belong to classes such as NSAIDs or opioids. Antifungal medications specifically target fungal infections, which is a different category of pathogens that penicillin does not act against. Lastly, while some vaccines may involve components derived from bacterial products, penicillin itself is not used as a vaccine component and does not play a direct role in vaccination. Thus, penicillin’s identification as a safe antibiotic highlights its role in combating bacterial infections, justifying the selection of that option.