Final answer:
If the telomere is lost and replication occurs, the ends of chromosomes cannot be fully replicated, leading to progressive DNA loss. Telomerase resolves this issue by elongating the ends of the chromosomes with repetitive sequences, allowing DNA polymerase to complete replication without loss of genetic information.
Step-by-step explanation:
When the telomere is lost and replication occurs, the problem faced is that the lagging strand of DNA cannot be fully replicated because there is no place for a primer to attach at the very end of the chromosome. This results in the loss of DNA with each round of replication, potentially leading to the loss of important genetic information over time. However, cells have a mechanism to prevent this problem. An enzyme called telomerase adds telomeric repetitive sequences to the ends of linear chromosomes.
In humans, the telomere sequence is TTAGGG, repeated hundreds to thousands of times. Telomerase, with its RNA template, extends the 3' end of the lagging strand, providing a template for DNA polymerase to add the complementary nucleotides, thereby preventing the strand from getting progressively shorter after multiple rounds of replication. Without telomeres and the action of telomerase, the sticky ends where the primers were placed for replication of the lagging strand would ultimately lead to the loss of vital genetic information and compromise cellular function.