Final answer:
True, telomerase is an enzyme involved in the replication of the ends of eukaryotic chromosomes. It extends the 3' end of the DNA to prevent loss of genetic material. Telomerase is active in various cell types and is associated with aging and cellular longevity.
Step-by-step explanation:
Role of Telomerase in Chromosome Replication
True, telomerase is an enzyme involved in the replication of the ends of eukaryotic chromosomes, known as telomeres. Telomerase consists of a catalytic part and a built-in RNA template, which helps to maintain the integrity of chromosome ends during DNA replication. As the replication machinery cannot fully replicate the very ends of chromosomes, telomerase extends the 3' end of the DNA strand by adding repetitive nucleotide sequences using its RNA as a template. This extension allows DNA polymerase to complete the synthesis of the lagging strand, thereby ensuring that the genetic material is not lost with successive cell divisions. Telomerase is especially active in germ cells, adult stem cells, certain protozoans, and in some cancer cells. It serves as a protective feature for chromosomes and, interestingly, has been associated with aging in the context of adult somatic cells where it is typically not active.
Elizabeth Blackburn, along with colleagues Carol W. Greider and Jack W. Szostak, received the Nobel Prize for Medicine or Physiology in 2009 for their discovery of telomerase. This discovery has profound implications for our understanding of cellular aging and has been a crucial step in the field of chromosomal biology.