Thoughts Concerning Rejuvenation
Of course, it's all guesswork for me, but for unicellular lifeforms, I'm going to suppose that the rectification of the parent cell takes phase in the centromeric phase, before the cell divides.
Let's run through an imaginary scenario in wnich a
paramecium is reconstituted prior to fission.
Something has to occur to trigger the reproductuve and restorative cycle.
A paramecium might be of the order of 20 microns long by
10 microns in diameter, or about 1,500 cubic microns in colume.
One cubic micron is one billion cubic nanometers. There
might be something like 100 atoms in a cubic nanometer. An organic molecule
might occupy anywhere from 1 to 1,000 cubic nanometers (for a very complex
macromolecule). A unicellular organism would be therefore be constituted of 1
billion to 1 trillion molecules. Let's call it a trillion. This means that a
cell would be constructed of about as many molecules as a puppy is of cells.
Now let's consider how this rejuvenation process might
work.
As a by-product of their metabolic cycles, cells
accumulate, with advancing age, perhaps several billion molecules of a
yellowish-brown sludge that's called "lipofuscin". It's normally insoluble, and
can't readily be eliminated by the cell. It must be cleared fom the cell at the
moment of reproduction. So how can this be accomplished? Presumably, several
billion molecules of special "detergent" molecules must be manufactured by the
sub-microscopic chemical factories in the cell's organelles. These must then
circulate throughout the cell, attaching to the lipofuscin molecules and
somehow, flushing them through the cell's membrane to the outside. In addition,
the excess "detergent" molecules must also be flushed from the cell. (Both
objectives would be met if the "detergent" molecules are excreted from the cell
carrying any attached lipofuscin molecules with them. However, they would have
to retained within the cell long enough for them to capture all the unattached
lipofucsin molecules.) Another way this might work would be if the "detergent"
molecules acted as catalysts, helping the lipofucsin molecules combine with
other substances in the cytoplasm (water, fat) that would chemically alter them
so that they would become evictable by the cell. Here again, the "detergent"
molecules would have to scavenged from the cell once they've done their job.
But however it works, somehow, Nature makes it happen.
At the Nanotechnology Level, Everything Works
Mechanically
This statement
isn't exactly correct, because nano-objects interact with each other through
short-range forces. However, they interact through direct contact rather than at
a distance. Individual molecules are harnessed like Legoes to construct living
organisms.
Cleaning Up the Genome
One
mystery to me is how the genome can be completely repaired. It has been observed
that DNA is stored redundantly as a double helix, so that there is a backup
template on one strand to repair DNA when a gene on the other strand is damaged.
However, neutrons disrupt both strands of DNA simultaneously. You wonder how
this DNA damage is repaired. Could it be that the duplicate stretches of genes
on a chromosome are there to provide additional redundancy for DNA repair?
Buy
Bonds and Real Estate Investment Trusts Now?
There is an abundance of articles recommending buying
bonds and real estate investment trusts (REITS) right now. There is little
question that the next move in interest rates will be up. This is the worst
possible time to buy bonds and to buy real estate stock. When interest rates go
down, the value of your bonds go up. But with 3-year interest rates on
government bonds running a little over 3%, and rates on interest-bearing
accounts running about 1.5%, interest rates can't go much lower. When interest
rates go up, the 10-year Treasury bonds you own that pay 4.4% aren't going to be
as attractive to you or to any potential buyers of your bonds as new Treasury
bonds that pay 6.6%. So the value of your bonds go down as interest rates go up,
and you lose money. Why are these articles recommending that you go out and buy
bonds now? You wonder.