Why Cohesive (Sticky) ends ligation is efficient over blunt end CSIR/DBT/ICMR JRF exams

The ligation of complementary cohesive ends is much more efficient. Because cohesive ends can base pair with one another by hydrogen bonding, forming relatively stable structure for enzyme to work on and form a phosphodiester bond between them.

The ligase is unable to catch hold of the blunt end molecules to be ligated. And has wait for chance association to bring ends together

Blunt ligation can be successful by increasing the concentration of insert molecules to increase the chance of association.