telomerase binds to the “overhanging” section of single stranded DNA. Telomerase adds deoxyribonucletides to the end of the parent DNA, extending it. … Primase, DNA polymerase, and ligase then synthesize the lagging strand in the 5′ to 3′ direction, which prevents the chromosome from shortening.
How does telomerase prevent linear chromosomes from shortening during replication?
Explain how telomerase prevents linear chromosomes from shortening during replication. Telomerase binds to the overhang at the end of a chromosome. Once bound, it begins catalyzing the addition of deoxyribonucleotides to the overhang in the 5′ -> 3′ direction, lengthening the overhang.
What is the role of telomerase in replicating the ends of linear chromosomes?
Telomerase adds complementary RNA bases to the 3′ end of the DNA strand. Once the 3′ end of the lagging strand template is sufficiently elongated, DNA polymerase adds the complementary nucleotides to the ends of the chromosomes; thus, the ends of the chromosomes are replicated.
Why is telomerase important in linear chromosomes?
The ends of the linear chromosomes are known as telomeres: repetitive sequences that code for no particular gene. These telomeres protect the important genes from being deleted as cells divide and as DNA strands shorten during replication. … Telomerase adds complementary RNA bases to the 3′ end of the DNA strand.
Why do chromosomes shorten at each replication?
Why do telomeres get shorter? Your DNA strands become slightly shorter each time a chromosome replicates itself. Telomeres help prevent genes from being lost in this process. But this means that as your chromosomes replicate, your telomeres shorten.
How do you reduce telomere shortening?
Dietary restriction, appropriate diet (high fiber, plenty of antioxidants, lean/low protein, adding soy protein to diet), and regular exercise can potentially reduce the rate of telomere shortening, disease risk, and pace of aging.
How do you prevent telomeres from shortening?
Some tips for how you can help slow down telomere shortening include:
- Maintain a healthy weight with healthy eating.
- Exercise regularly.
- Quit smoking.
- Get enough sleep.
- Reduce or manage stress.
- Eat a telomere-protective diet full of foods high in vitamin C, polyphenols, and anthocyanins.
How do telomeres solve the end replication problem?
Eukaryotes have solved the end-replication problem by locating highly repeated DNA sequence at the end, or telomeres, of each linear chromosome. … In prokaryotes, the end-replication problem is solved by having circular DNA molecules as chromosomes. Another cause of telomere shortening is oxidative stress.
Do prokaryotes have multiple origins of replication?
In prokaryotic cells, there is only one point of origin, replication occurs in two opposing directions at the same time, and takes place in the cell cytoplasm. Eukaryotic cells on the other hand, have multiple points of origin, and use unidirectional replication within the nucleus of the cell.
What role does telomerase play in DNA replication?
They protect chromosome ends from DNA degradation, recombination, and DNA end fusions, and they are important for nuclear architecture. Telomeres provide a mechanism for their replication by semiconservative DNA replication and length maintenance by telomerase.