NEETZoologyMolecular Basis of Inheritance
What is the role of DNA ligase in the process of replication?
Options
- Ato initiate replication
- Bto join discontinuously synthesized fragments
- Cto provide the origin of replication
- Dnone of the above
Correct answer
B. to join discontinuously synthesized fragments
Step-by-step solution
For long DNA molecules, since the two strands of DNA cannot be separated in its entire length (due to very high energy requirement), the replication occurs within a small opening of the DNA helix, referred to as replication fork. The DNA-dependent DNA polymerases catalyze polymerisation only in one direction, that is 5'🡪3'. This creates some additional complications at the replication fork. Consequently, on one strand (the template with polarity 3'🡪5'), the replication is continuous, while on the other (the templat