Question

Which of the following statements about telomerase is false? Which of the following statements about telomerase is false? Telomerase is a ribonucleoprotein. Telomerase acts to elongate the 3' end of linear DNAs. Telomerase has reverse transcriptase activity. Telomerase replaces the final RNA primer with DNA during DNA replication. Telomerase generates a new primer:template junction by providing its own template.

Answer 1

Answer:

Telomerase acts to elongate the 3' end of linear DNAs.

Explanation:

The 5' ends of the linear DNA can not be replicated by DNA polymerase due to the absence of free 3' end to be elongated. This is prevented by the action of telomerase enzyme which contains both RNA and protein components. The RNA component of the telomerase is 150 nucleotides long.

The telomerase enzyme elongates the 3' end of the template strand by using its inbuilt RNA template. Since it uses an RNA template to make the DNA copies, it is a reverse transcriptase. Repeated translocation and repositioning of the enzyme elongates the 3' end of the template DNA.

The RNA primase makes the RNA primer at the end of the new telomere strand which is then elongated by DNA polymerase. DNA ligase seals the nick. In this way, telomerase serves to prevent the loss of 5' ends of linear DNA in successive rounds of DNA replication.