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[StuartNYC]

Back in 2000 I did my Senior paper on the evolution of the cell and how after evolving more complex mechanisms had to incorporate the mitochondrion as one of it's organelles to harness oxygen protons for the manufacturing of ATP.  As a consequence, the single-celled eukaryotes had no way to completely neutralize the free oxygen radicals created as a by-product of glycolosis. The eventualbuild-up of these radicals is what leads to cell senescence or as the layman calls it, aging and ultimately death.

My mother, who after having retired has gone back to school has to write a paper for her Biology class.  She has always shown interest in this topic so I agreed to help her understand certain concepts. 

Since my paper is almost ten years old, much of the research cited is out-dated.  I'm doing my best to direct her to some sources that explain the latest research and findings in the field without actually having to do the research all over again myself.  She is having a hard time finding anything that coincides with and builds on the information I had cited in my paper.  If any of you are following this research could you please direct me to a useful starting point that I could forward to my mother?  Thanks in advance.

[luberjz]

Oxidative stress is one out of several proposed mechanisms of aging, and is likely part of a combination of factors which ultimately lead to cellular senescence.  Here's a recent review of the topic.
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Maybe I'm misreading your post, but as I see it I have to disagree with you about eukaryotic cells having no way to neutralize free radicals.  There are a number of compounds - both exogenous and endogenous - that prevent the formation of free radicals and that also neutralize the radicals after they've formed.  Overall oxidative stress isn't a matter of cells having no way to manage free radicals, but rather is the result of acquired inefficiencies in an otherwise capable antioxidant defense system.

[StuartNYC]

Oxidative stress is one out of several proposed mechanisms of aging, and is likely part of a combination of factors which ultimately lead to cellular senescence.  Here's a recent review of the topic.
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Maybe I'm misreading your post, but as I see it I have to disagree with you about eukaryotic cells having no way to neutralize free radicals.  There are a number of compounds - both exogenous and endogenous - that prevent the formation of free radicals and that also neutralize the radicals after they've formed.  Overall oxidative stress isn't a matter of cells having no way to manage free radicals, but rather is the result of acquired inefficiencies in an otherwise capable antioxidant defense system.

Thanks so much for the link.  I'll check it out.  I probably should have been more clear.  You are correct.  When I said that eukaryotes had not developed such a mechanism, I meant to a 100% efficient level.  Antioxidants and telomerase play a huge role in neutralizing and repairing DNA, but ultimately are not efficient enough to have prevented them from evolving a "cell death" gene.   Prokaryotes, without the luxury of incorporating a symbiotic organism into its cell membrane had to develop it's own way of neutralizing free radicals.

[Anders]

We also have peroxisomes. But there's no shortage of theories about aging.