Final answer:
During DNA replication, the lagging strand is synthesized in segments and the last segment poses a challenge at the chromosome end. Telomerase extends the 3' end of the DNA, allowing for the complete synthesis of the lagging strand and preventing genetic information loss.
Step-by-step explanation:
The question relates to DNA replication, specifically what happens to the template strand during and after replication, and involves the action of telomerase in extending the length of one of the strands. During DNA replication, one strand, the leading strand, is synthesized continuously, while the other strand, known as the lagging strand, is synthesized in sections called Okazaki fragments. When the replication reaches the end of a chromosome, there's an issue in completing the lagging strand because there's no upstream template for the last RNA primer to be replaced with DNA.
Telomerase extends the 3' end of the template, allowing room for an additional Okazaki fragment to be synthesized, which ensures that the genetic information at the ends of the chromosomes is not lost during replication. This process is crucial for protecting the integrity of the genome.The Role of Telomerase Telomerase is an enzyme composed of both RNA and protein subunits that extends the 3' end of the template strand. This extension by telomerase allows for the priming and synthesis of the last Okazaki fragment even at the very end of the chromosome. This process prevents the gradual shortening of DNA with each cell division, which is particularly important for maintaining chromosome stability in eukaryotic organisms.