Question

Antibiotic resistance worked on by Lederberg's replica experiment proves

• A. Genetic drift
• B. Natural selection
• C. Chemical mutations
• D. Founder's effect

Answer 1

The correct option is B Natural selection

Joshua Lederberg and Esther Lederberg showed the genetic basis of adaptations in bacteria by culturing bacterial cells by their plating experiment. Lederberg's replica plating experiment provided a support to neo-Darwinism and proved that the penicillin-resistance adaptation in the bacterial cells originated due to selection of pre-existing mutant forms of bacteria by nature. Excessive use of herbicides, pesticides, antibiotics, etc., has resulted in selection of resistant varieties in lesser time scale. These are examples of evolution by anthropogenic actions and prove that evolution is not a directed process but is a stochastic process based on chance events in nature and chance mutation in the organisms.

Therefore, the correct answer is option B.