[mage lang=”en|es|fr|en” source=”flickr”]telomerase replication[/mage] HELP multiple choice?
The enzyme telomerase solves the problem of replication at the ends of linear chromosomes by which method?
A)adding a single 5′ cap structure that resists degradation by nucleases
B)adding numerous GC pairs which resist hydrolysis and maintain chromosome integrity
C)adding numerous short DNA sequences such as TTAGGG, which form a hairpin turn
D)causing specific double strand DNA breaks that result in blunt ends on both strands
[mage lang=”en|es|fr|en” source=”flickr”]telomerase dna replication[/mage] DNA replication question?
how does shortening of the telomeres(leading to unstable chromosomes which will result in the cell line dying) occurs if the telomeric loss can be compensated by the enzyme telomerase?
That’s a good question.
In yeast, protozoa and other single-celled organisms, telomerase is active. These cells can divide forever. However, in most cells of higher organisms, telomerase is inactive and the ends of the chromosomes get shorter with each cell division. At a certain telomeric length, the cells no longer divide.
However, if telomerase becomes active, and the ends of the chromosomes lengthen, a signal is conveyed for cells to keep dividing, which can lead to cancerous growth.
[mage lang=”en|es|fr|en” source=”flickr”]telomerase tumor[/mage] Two genes linked to why telomeres stretch in cancer cells
Scientists at Johns Hopkins have provided more clues to one of the least understood phenomena in some cancers: why the “ends caps” of cellular DNA, called telomeres, lengthen instead of shorten. TSNa: Telomerase Specific Nanorobots
Can anyone give me a simplified version of telomere replication?
If DNA polymerase a adds nucleotides to the 3′ end of the RNA template of telomerase, is the RNA template never removed? Because otherwise the lagging strand would shorten again :S
the RNA templates are always removed.the DNA plo 1 removes the RNA tepmlates and replaces them with deoxybases.as the bases are just replaced and not removed sp there wont be any chnage n th length of the DNA chains.