We Are a Synthesis of a Lot of Little Things

We Are a Synthesis of a Lot of Little Things

There are a lot of little things we don't ever think much about but
without a synthesis of all the little things there would be no big things.
We think in terms of "us" when us is really a whole bunch of them. Maybe
that doesn't make a whole lot of sense to you right now, but hopefully it
will as I go forward with this - for those of you who read it to the end
because you are asking yourself, "What the hell is he talking about?"

We all realize that we will change as we age. I wrote to my brother's girl
friend a few days about this, but in much less detail than I will here. I
was answering her note about my brother's age which I underestimated by
a few years and she correct ed me but my perspective on age is different
than hers because I tend not to think about chronological age as much as I
do the transformation we go through continuously, some of us slower than
others because of oxidative stress and other genetic reasons behind why we
wear out (our cells) and why we lose the ability to fight immunological
assaults on the host; that collection of cells which together form what we
are.

We are all an amalgam of various chemical constituents but those same
chemicals exist in other amalgamations. Life is determined by behavior of
those chemicals. Like Lynn Margulis tells us life is more of a verb than a
noun. It is not just those chemicals but how those chemicals self-sustain
themselves, how this thing we call life "repairs, maintains, recreates.."

That behavior of cells is more than just heredity and the blueprint for
life in DNA is more than just replication.

No one can reduce what happens after reproduction to a simple process.
Biological process and the decline of function is a very complex
phenomenon. Some age faster. Individuals within species don't age in
exactly the same rate. There are variations in their metabolism, in their
environment and also their genetic background.

We are not simply the result of heredity. The primary purpose of DNA in
each of our nucleated cells is production of proteins, which are composed
of amino acids which are the end result of specific sequences of the
language of DNA and that blueprint is a genetic cipher of three letter
words (codons) which are combinations of four letters: A,C,T and G
* (adenine, cytosine, thymine and guanine)

RNA is like DNA, a long macromolecule of sugarphoshate backbone and FOUR
bases, repeating subunits. DNA is a double stranded molecule which
replicates. DNA is entwined strands, a double helix - and the separate
strands are each templates for each other.

RNA is a single stranded molecule that does not replicate. They share
three bases A,G & C. DNA and RNA differ in one base. In DNA thymine is
replaced in RNA by uracil. There are also three different types of RNA:
messenger RNA (mRNA), transfer RNA (tRNA), and ribonsomal RNA (rRNA). AND,
RNA is 10 times more abundant than DNA in eukaryotic cells.

During cell division the double strand of DNA each provides the blueprint
to reconstitute another full double helix for two identical copies.
Gene is the code for a single protein and the genome is the library of
genes by an organism.

This is not a thesis and I don't want to get into too much complexity -
though for some of you I'm sure I have already gone too far, but really
what I have described are just the basics. And, furthermore, I'm not a
scientist, but I understand this much. I just want to mention one
additional function of RNA.

Cells build proteins with RNA. The messenger RNA exited the nucleus going
into the cytoplasm (the rest of the cell) where the code of life is read
by ribosomes and that is where amino acids are strung together in the
order prescribed by the mRNA bases. In cytoplasm there are these
ribosomes, but also lipids and mitochondria. There are hundreds of
mitochondria, which has its own DNA and it comes only from the mother -
although there have been some exceptions of mitochondria passed on from
male sperm. There are hundreds of mitochrondria in each cell unless it is
a metabolic-ally active liver, kidney, muscle or brain cell where the
mitochondria organelles is as much as 40% of the cytoplasm.

As noted these come from the maternal lineage. The egg or oocyte pass on
about 100,000 mitochondria. Blood cells and skin cells have very few
mitochondria - or NONE at all. In male sperm there is less than 100
mitochrondria so very few, if any, are passed on. All together there are
about 10 billion mitochondria in a _human adult_.

In an adult human mitochondria is about 10% of body weight.

The code in DNA is made up of the four chemicals are 3-letter words which
are transcribed to RNA, the mirror image of DNA, and the errors in
transcription, which are introduced by viruses, by radiation, pollution,
etc. are debugged in the RNA and most of them are fixed - but some of them
are a benefit and those changes which survive are the proteins which
benefit the host organism; that is, considered better able to survive to
produce and over a very long time those are what is evolutionary change.

The amino acids from RNA produce proteins; the corpus of all eukaryotic
living things. There are many different combinations of instructions of
amino acids for the same proteins.

Proteins have almost (seemingly) infinite functions which presents in a
rich variety of life. And proteins fall into broad groups according to
their functions, such as metabolism and movement, flight and sight,
immunity and signaling, hormones, antibodies, DNA binding, histones,
structure, receptors and enzymes which are also referred to as the
catalysts.

This was one of life's secrets until only recently. Most of what
we know now wasn't taught when I was in high school because it wasn't
known then. Even today what was taught in the college in the 90s has
changed. It is so important to continue to read and know the research
because we are learning new secrets of life everyday.

It is therefore not surprising that no two species or individuals within a
species would age in exactly the same way nor does variability from DNA
and from mutations, environment, genetics, metabolism, etc. result in
exact copies of individuals.

Most of our current knowledge is just at the beginning of this vast body
of information of underlying mechanisms which affect aging and behavior.

"Replicative or cellular senescence was observed and proposed as a model
for aging at the cellular Level over thirty years ago by Leonard Hayflick
(1965; Hayflick and Moorhead, 1961)." (Replicative senescence -
Generations - April 1, 2000 Bertram, Michael J; Pereira-Smith, Olivia M)

Oxidative stress, though not the only theory of aging, but the most
important theory is part of a complex process where genetics and
environment both affect aging - along with mutations from pollution, gene
transfer from viruses and bacteria and other reasons we haven't even
discovered yet.

At the smallest level of life, oxidative stress on cellular replication
and survival has the effect of limiting and sustaining life.

Hank Roth
http://pnews.org/