Which of the following scientists determined the biochemical nature of ‘transforming principle’ in Griffith’s experiment?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Oswald Avery, Colin MacLeod and Maclyn McCarty
(1) Francis Crick — Incorrect. Crick worked with James Watson to propose the double helix model of DNA.
(2) Alfred Hershey — Incorrect. Hershey, with Martha Chase, showed with radioactive viruses that DNA is the genetic material. This came after the work on the transforming principle.
(3) Oswald Avery, Colin MacLeod and Maclyn McCarty — Correct. Griffith showed that something from heat-killed S cells could change live R cells. These three scientists purified proteins, DNA and RNA from the S cells. They found that DNA alone caused the change, and so they identified the transforming principle as DNA.
(4) Walter Sutton — Incorrect. Sutton, with Boveri, put forward the chromosomal theory of inheritance.
NCERT Extract:
The Search for Genetic Material – …
