Final answer:
Telomeres are indeed only a component of linear chromosomes, and they are extended by the enzyme telomerase, which is crucial for preventing the loss of genetic information during cell division. The correct answer to the question on maintenance of linear chromosome ends is option d. telomerase.
Step-by-step explanation:
The statement that telomeres are only a component of linear chromosomes is B. True. Telomeres consist of noncoding repetitive TTAGGG sequences that protect the ends of eukaryotic, linear chromosomes during cell division. As cells divide, these ends can become progressively shorter, which could lead to the loss of important genetic information. However, the enzyme telomerase helps to maintain these ends by adding nucleotides to the 3' end of DNA, extending the telomeres, and thereby protecting the genetic data. Specifically, the question regarding the maintenance of telomeres can be answered with option d. telomerase, which ensures the elongation of the telomeres in certain cell types, such as germ cells, stem cells, and some cancer cells, allowing for continued division without the loss of genetic material.
Furthermore, Elizabeth Blackburn's Nobel Prize-winning research on telomerase underscored the importance of this enzyme in cell biology. The absence of primer placement at the ends of linear chromosomes necessitates the presence of telomerase, distinguishing the replication process of linear chromosomes from that of circular prokaryotic chromosomes.