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I disagree with Ctina. So many factors go into determining loss rate, activity of telomerase, gene conversion or unequal exchange at chromosome ends, etc to ever say that length is a function of age. There is far more variation between individuals and between cells within an individual than aging ever shows. Here is one study: Das B, Saini D, Seshadri M. ...

It would be reliable if we don't take into account the environment, and if we are comparing two genetically identical persons. First, because there are many other factors that can cause genetic mutation and consequently shorten lifespan. Second, giving an extreme example and not taking into account the environment and modern medicine, we cannot expect a ...

Gametes (sperm and ovum), which fuse to form a zygote, arise from germ cells [ spermatogonia and oogonia). Germ cells, like stem cells, are maintained carefully i.e the genome is preserved and transposition/recombination events are tightly controlled. So these germ cells don't have shortened telomeres. Also, during early embryonic development the future ...

Hydra are just one of the many organisms which are immortal. That is to say all their cells divide forever - there is no senescence (planned cell death) in any of their cells. Interestingly Hydrae that reproduce sexually age and die, but asexual reproduction appear to be immortal. Animals that are immortal more often reproduce asexually... this may only ...

Again, not an expert, but I found this article seems to say it pretty well: Telomere's are most commonly measured by qPCR of the repetitive regions with degenerate oligomer sequences such as "TTAGGG and CCCTAA repeats" Although articles like this one appear to advance measurements in vertebrates, this reference from 2011 implies two techniques continue to ...

I've been doing some reading, and have come up with the following interesting information. Telomeres During cell division the DNA is replicated, but the mechanism is imperfect and in each round of cell division a small section is lost from the end of each chromosome. To compensate and protect the genetic information there are caps – regions of excess ...

A number of studies have compared replicative capacity of cells with lifespan. Since Replicative capacity of cells is linked to telomere-length, these studies may provide indirect evidence for the association between telomere length and lifespan. One interesting study in particular compared animal life spans and in vitro replicative capacity of skin ...

Telomerase activity is just one (probably minor) facet of aging. It takes a lot more than just basic end repair of DNA to keep a complex organism alive, especially mammals. Just a few issues off the top of my head: repairing oxidative stress to DNA and proteins repairing UV damage to DNA keeping cells clean of debris like protein aggregate buildup (think ...

Actually, most adult cells do not express telomerase or express it only at a very low levels. Telmoerase is highly expressed only in cells that need to divide (e.g. stem cells), thus "immortalizing" them. In fact, human cell lines which scientists work with can be "immortalized" by activation of telomerase (along with other things). So you may ask yourself: ...

During mitosis the genetic material in the cell is replicated to produce a copy of the genome for each resulting daughter cell. Due to the nature of the process, the ends of the chromosomes are not completely replicated, resulting in a slightly shorter copy of each chromosome after each round of replication. Telomeres are extensions to the end of ...