AP BIOLOGY

Detailed explanation-1: -The best-known mechanism to lengthen short telomeres is the enzyme telomerase, a reverse transcriptase complex that contains hTERT (the reverse transcriptase) and hTR (the RNA template). Telomerase elongates telomeres by adding TTAGGG repeats to the ends of chromosomes.

Detailed explanation-2: -(a) Telomere length can be prevented from shortening by an enzyme Telomerase. Telomerase has a protein subunit (hTERT) and an RNA subunit (hTR). This enzyme is active in germline and stem cells and maintains their telomere length by adding ‘TTAGGG’ repeats to the ends of chromosomes.

Detailed explanation-3: -An enzyme in cells that helps keep them alive by adding DNA to telomeres (the ends of chromosomes). Each time a cell divides, the telomeres lose a small amount of DNA and become shorter. Over time, the chromosomes become damaged and the cells die.

Detailed explanation-4: -Telomerase-the enzyme responsible for protecting chromosome ends from shortening during DNA replication to avoid potentially catastrophic DNA loss-is an RNP composed of the telomerase reverse transcriptase (TERT) protein and the telomerase RNA (TR) among other constituents.

Detailed explanation-5: -Telomerase: the key telomere length maintenance mechanism Telomerase is a large ribonucleoprotein complex responsible for progressive synthesis of telomeric DNA repeats (TTAGGG) at the 3′ ends of linear chromosomes, thereby reversing the loss of DNA from each round of replication.