What is the main purpose of DNA ligase in the context of DNA replication?

In the context of DNA replication, the main purpose of DNA ligase is to join DNA strands together. During DNA replication, the enzyme plays a critical role in sealing the gaps between Okazaki fragments, which are short segments of DNA synthesized on the lagging strand. As the replication process occurs, these fragments are initially created separately because DNA polymerase can only synthesize new DNA in one direction (5' to 3'). After the RNA primers, which initiate the synthesis, have been replaced by DNA, ligase comes into play to create a continuous strand by forming phosphodiester bonds between adjacent nucleotides. This action ensures the structural integrity of the new DNA molecule, allowing it to function correctly during cell division and other cellular processes.