Question

The name of the experiment performed by Lederberg is

• A. Replica plating experiment
• B. Tissue culture
• C. Protoplast fusion
• D. Hybridisation

Answer 1

Answer: (A)

Replica plating experiment

Lederberg experiment is also known as replica plating experiment. They spread the diluted bacterial cultures on nutrient medium plates and incubated till visible bacterial colonies observed. Next step involves inversion and pressing of plates over velvet cloth, then the same velvet cloth were gently pressed over nutrient medium plates containing antibiotic ampicillin and incubated. After incubation, rare ampicillin resistant colonies had formed that can easily thrived in plane nutrient medium and gave rise to ampicillin resistant colonies. This procedure is known as replica plating technique. The growth of resistant colonies on plane nutrient medium demonstrated the existence of antibiotic-resistant colonies in a population of bacteria prior to their exposure to the antibiotic.