Question

During replication of DNA, its two strands separate. Each of these serves as a template for the formation of new strands. Such type of replication is called

• A. non-conservative
• B. semi-conservative
• C. flexible
• D. conservative

Answer 1

Answer: (B)

Since, each daughter DNA molecule contains one strand of the parent DNA double helix (only one strand synthesised afresh), the process of replication is called semi-conservative. Mathew Meselson and Franklin Stahl in $1958$ proved experimentally that DNA replication is semi-conservative. To prove it, they used $N^{15}$ heavy DNA in a medium containing $N^{14}$ isotope.