Question

What specific constraint to DNA replication occurs at the ends of linear DNA molecules? How does replication occur at the ends of linear DNA molecules in eukaryotes?​

Answer 1

• What specific constraint to DNA replication occurs at the ends of linear DNA molecules?

→DNA polymerase cannot replicate and repair DNA molecules at the ends of linear chromosomes. The ends of linear chromosomes, called telomeres, protect genes from getting deleted as cells continue to divide.

• How does replication occur at the ends of linear DNA molecules in eukaryotes?

→The ends of the linear chromosomes are known as telomeres: repetitive sequences that code for no particular gene. Once the 3′ end of the lagging strand template is sufficiently elongated, DNA polymerase adds the complementary nucleotides to the ends of the chromosomes; thus, the ends of the chromosomes are replicated.