National Dental Examining Board of Canada (NDEB) Practice Exam

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Prepare for the National Dental Examining Board of Canada (NDEB) Exam. Gain confidence with our comprehensive quizzes that include detailed explanations and hints to help you understand key concepts. Excel in your dental career!

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Which penicillin is most effective against gram-negative bacteria?

  1. Penicillin G

  2. Ampicillin

  3. Amoxicillin

  4. Penicillin V

The correct answer is: Ampicillin

Whereas Penicillin G, Penicillin V, and Amoxicillin are most effective against gram-positive bacteria, Ampicillin is unique in its effectiveness against both gram-positive and gram-negative bacteria. This is due to its ability to bind to and inhibit the growth of the cell walls in both types of bacteria. Thus, Ampicillin is the best option when targeting gram-negative bacteria.