| There is a hypothetical challenge that I
would like you to consider. It is a challenge between two sides that I have named the
Super Labs and the Primordial Soup. They are to be set against each other in a
competition. It is a important challenge because it pits all the cumulative intelligence
and scientific horsepower harnessed by human beings against the awesome powers of nature.
The challenge - create any living organism from scratch. The definition of
‘scratch’ is quite plain and simple. The challenging sides may use any
components or organic chemicals as long as there is absolutely no life in any of the raw
ingredients.
Before we get too far into the details of this challenge
and try to establish which side is successful and why, we need to first consider the
starting points and strengths of the members involved in the competition. Let us begin
with nature’s side, Primordial Organic Soup, as it is sometimes referred to. What is
a good description of the strengths, conditions, content and early settings for the
primordial soup?
To find descriptions of primordial conditions and some theories on how life may have
originated, I sought out two references. One reference is quite old, from the 1960’s,
and comes from the biology textbook that I used in high school. The particular reference
that was found is a short and succinct description. The text is quoted completely, as
follows:
The Origin and the History of Life
Several billion years ago, when the earth was vastly different from what it is
today, the primeval seas became rich mixtures of organic molecules. Probably a chance
combination of molecules produced a larger molecule (similar to the DNA of today?) that
had a chemical structure giving it a pattern for exact duplication. Slowly, the
duplicating molecules became parts of more complex systems, until - perhaps after one or
two billion years - they could be called "organisms." From these humble
beginnings life spread over the earth and evolved into its innumerable species - each an
experiment in living in a particular way.
Biological Science - An Inquiry into Life. © 1963 by the American Institute of
Biological Sciences. Harcourt, Brace & World, Inc.
The complete chapter entitled "The Origin and the History of Life", which is
part of the textbook, goes into substantially more detail and elaborates on the previous
reference. To be completely fair though, I felt that instead of describing the theories of
primordial soup and the early life it yielded from the vantage of this textbook, a second
modern reference should be found to ensure better credibility and provide a more current
state on the scientific theories about the origins of life.
However, before I leave that older textbook, the chapter also included a photograph of
the laboratory apparatus for a famous experiment. In May 1953, Stanley Miller published
his paper called "A Production of Amino Acids Under Possible Primitive Earth
Conditions." The picture shows the actual laboratory equipment used in the experiment
that demonstrated amino acid synthesis in a simulated primitive atmosphere. While this has
been a digression, we have started to build a picture, albeit somewhat dated, of our
challenging team: the Super Labs.
For some, this may seem to be pretty intellectual material. What is an amino acid? Do
not worry about some of these concepts or details at this point. Later, there is a chapter
on biology that goes into a few of these subjects and gives some plain and straightforward
explanations. The chapter on biology also takes a look at this area of science from a
totally different viewpoint. For now, the present intent is to deal with the subject
matter on a higher level to gain the big picture, so to say. Are we going to get pulled
into a vortex of complicated biological terms? The answer to this question is not for very
long.
The second more modern reference that follows may get slightly cerebral, but I would
not be overly concerned about it. Unless you are well versed in such material, please just
read it patiently and slowly to obtain the best grasp and understanding of the material.
Then we will come back out of the vortex, to the higher ground and examine the big
picture. The following text is a direct quote from a computer based encyclopedia available
on a compact disk.
Origin of Life and Evolution of Cells
Scientists have formulated many theories about the origin of life and how it
evolved into the various forms known today. These ideas are deduced from the evidence of
the fossil record, from laboratory simulations of conditions on the primeval earth, and
from consideration of the structure and function of cells.
The earth was created more than 3 billion years ago, although more than 2 billion years
probably passed before life as it is now known developed. Scientists believe that the
atmosphere of the young earth was mostly water vapor, methane, and ammonia, with very
little gaseous oxygen. Laboratory simulations have shown that all major classes of organic
molecules could have been generated from this atmosphere by the energy of the sun or by
lightning and that the lack of oxygen would prevent newly formed organic molecules from
being broken down by oxidation. Rain would have carried these molecules into lakes and
oceans to form a primordial soup.
When the concentration of organic molecules in this soup became high enough, molecules
would have begun to form stable aggregates. For example, lipids might coalesce into
droplets the way cooking oil does in water, thus generating simple membranes and trapping
other organic molecules in the interior of the droplet. Randomly formed aggregations that
could harness energy to grow and reproduce themselves would eventually far outnumber other
combinations. DNA may have been an essential component of the self-reproducing aggregates;
it and RNA are the only organic molecules able to duplicate themselves. These
supramolecular aggregations would have been extremely lifelike and with some refinements
would have resembled primitive prokaryotes. This concept of the origin of life, however,
does not explain the development of the genetic code and the precise interdependence
between the code and protein synthesis.
The relative absence of oxygen from the atmosphere of the young earth meant that no
ozone layer existed to screen out ultraviolet radiation and no oxygen was available for
aerobic respiration. Therefore, the first cells were probably photosynthetic and used
ultraviolet light. Because photosynthesis generates oxygen, the oxygen content of the
atmosphere gradually increased. As a result, cells that could use this oxygen to generate
energy, and photosynthetic cells that could use light other than ultraviolet, eventually
became predominant.
Eukaryotes may have evolved from prokaryotes. This idea comes from speculation about
the origin of mitochondria and chloroplasts. These organelles may be the degenerate
descendants of aerobic and photosynthetic prokaryotes that were engulfed by larger
prokaryotes but remained alive within them (endosymbiosis). Over the years the host cell
became dependent on the endosymbionts for energy (ATP), while they in turn became
dependent on the host for most other cell functions. The fact that mitochondria and
chloroplasts are surrounded by two membranes, as if they had originally entered the cell
by phagocytosis, supports this theory. In addition, these organelles contain their own DNA
and ribosomes, which resemble the DNA and ribosomes of bacteria more than those of
eukaryotes. It is possible that other eukaryotic organelles originated similarly.
"Cell," Microsoft® Encarta® 97 Encyclopedia. © 1993-1996 Microsoft
Corporation.
Well, if you managed to get to this point and are still reading, you have survived the
most complex and technical portion of this chapter. Both of the foregoing descriptions,
being direct quotations, have done a reasonable job of describing one of the challenging
teams - the team which I refer to as the Primordial Organic Soup. Next, we will move on to
describe the other team that I refer to as the Super Labs.
Unfortunately, I was not able to find suitable reference material that could be quoted
to you and which would paint a picture of the Super Labs. So, it will be necessary to
construct the image for you, step by step. The effort of describing these labs began upon
the mention of the photograph and apparatus used by Miller to synthesize amino acids.
However, we need to describe the challenging team far more adequately than that.
To understand the technical sophistication and resources available to the Super Labs,
let us start with the biological, life sciences, and medical research labs first. We have
all likely seen these sophisticated labs either first hand through our own learning
experience, through tours of facilities, or via the various media that is presented to us
in terms of documentaries or news reports. You need to visualize the resources available
to a well equipped lab. Resources might range from: a wide spectrum of supplies; organic
and non-organic chemicals; high tech lab equipment for monitoring, controlling and
analyzing experiments; and, right up to specially designed buildings and labs for
controlling biological environments. The list of equipment would be almost endless and
probably would be contained in other smaller labs that specialize in the various
sub-fields of analysis or biology. There would be all types of specialized and costly
equipment including: light microscopes, electrophoresis equipment, baths and circulators,
incubators, pH equipment, fume hoods, and scanning electron microscopes - to name a few.
Biology is not the only science needed. Chemistry and biochemistry labs are just as
specialized and just as technical. Who has not seen chemistry labs with all the elaborate
glassware, chemical processes, heat sources, vacuum sources, cooling mechanisms and wide
arrays of chemicals in liquid, powder and all forms imaginable? They are also equipped
with sophisticated equipment for monitoring, controlling, and analyzing chemical and
biochemical reactions. Items like centrifuges, gas and liquid chromatograph equipment, and
mass spectrometers are available to determine the makeup of chemical, organic, and
biological materials.
Sciences such as physics should not be ignored. This science has equally advanced
apparatus such as particle accelerators, cyclotrons, and collider accelerators to study
the physics of atoms. Some of these structures occupy spaces bigger than football fields.
While biology may not require these labs to provide such a detail level of analysis,
physics offers all types of radiation sources that include: high voltage electricity to
simulate lightning, visible light sources, lasers, microwave, infrared, ultraviolet light
sources, X rays, and gamma rays. Physics can also provide electrical and electronic
analysis equipment, high pressures, low pressures, vacuums, temperatures, and different
gas atmospheres. Who has not seen pictures of a complex physics lab that looks like a
plumber’s dream of exotic metals, pipes, sensors, gauges, wires, and banks of
electronic instrumentation? (They might even keep an engineer handy to fix things.)
If you combine all of these visual elements in your mind, you start to get a sense of
the technical horsepower that exists in the world today. However, something that is vital
and extremely important from the description of the Super Lab team is missing - people.
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