Question

Who gave semi-conservative mode of DNA replication for the first time in E.coli with the help of $15 \,N$ heavy nitrogen isotope?

• A. Watson and Crick
• B. Kornberg and Ochoa
• C. Meselson and Stahl
• D. Luria and Delbruck

Answer 1

Answer: (C)

Meselson and Stahl

Answer 2

Mathew Messelson and Franklin Stahl $(1957-58)$ gave/prooved semi-conservative mode of DNA replication for the fist time in bacterium E coy/with help of $^{15}Na$ heavy isotope of nitrogen as postulated previously by Watson and Crick. Kornberg and Ochoa carried out the first in vitro synthesis of DNA with template and RNA respectively.