Telomerase, ar-enzyme implicated in aging and cell lifespan, helps overcome this problem. Telomerase adds additional deoxynucleotides to the end of the chromosome, lengthening it. This DNA sequence, or telomere, prevents the loss of essential DNA from the ends of chromosomes.
1. Which statements describe telomeres and the actions of telomerase?
O Telomerase activity is turned off in most human cells, causing the telomeres to gradually shorten as the individual ages.
O Telomerase contains a G‑rich template sequence that adds a C‑rich DNA sequence to the lagging strand of the chromosome.
O Inappropriate activation of telomerase can result in cellular immortality, one of the cellular changes implicated in the development of cancer.
O Telomerase consists of an RNA template and a protein component that adds complementary nucleotides to the 3′ end of DNA.
O A telomere forms a loop with a section of the complementary DNA strand, protecting the chromosome from degradation by endonucleases.