試題詳解

32. Telomerase is an enzyme can solve the problem of replication at the ends of linear chromosomes. How does it work?
(A) Repetitive sections of DNA can range from a single nucleotide to hundreds of nucleotides. Three nucleotides of smaller is a microsatellite.
(B) It adds 5' cap and 3’ polyA on chromosome that resists degradation by nucleases.
(C) It works like regular DNA polymerase (3'-5') except does not need DNA template strand to direct synthesis. Uses intrinsic RNA strand to synthesize GGGTTA sequence.
(D) It causes specific double-strand DNA breaks and rejoins the blunt ends on both strands.
(E) It adds numerous methylated GC pairs which resist hydrolysis and maintain chromosome integrity.