free radicals

[french at RUST.ZSO.DEC.COM]

Perhaps free oxygen radicals cause ageing indirectly
by their affect on other components within the cell
(such as enzymes) that determine which section of
DNA to read and execute.

One possibility is that free oxygen radicals and radiation
drive a molecular clock that drives the ageing process.
For example, let's say that there is an enzyme with two
or more stable states that can be flipped  back and 
fourth from one state to the other by a hit from a radical 
or radiation.  If this enzyme also advances the genetic
program by one step each time it takes a hit then you
would have a nice clock for driving the ageing process.

This hypothesis explains why:

   1. The rate of ageing is directly proportional to the
      concentration of free radicals and radiation.

   2. Ageing is relatively predicatable sequential
      process suggesting that there is some type of
      clock driving a predermined program.