File - FWC Apologetic Ministries

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Session 2 – Origins of Life
In this session we will look at the question
of the origin of life in evolution
We will look at several theories that
evolutionists have presented to explain how
life can come about naturally, and we will
see the problems associated with them
Much information is taken from Creation
Ministries International (Creation.com)
Biogenesis vs. Abiogenesis
The law of biogenesis,
attributed to Louis Pasteur,
is the observation that
living things come only
from other living things, by
reproduction
Abiogenesis is the opposite, and says living
things can arise and come about from non
living material
Pasteur has a famous
experiment that most
of us are familiar with
He proved broadly the
life comes from life
“Life does not arise spontaneously but comes
only from prior life, through reproduction…
Although life certainly originated from
nonliving matter at least once.” – integrated
Principles of zoology, thirteenth edition, pg. 6
We need to be careful when we get into this
debate that we know what we are talking
about when we say life
According to modern biology, life has five
characteristics to it
1.Energy
2.Cells
3.Information
4.Evolution
5.Replication
When we talk about creating life in the lab
we are not talking about creating full size
cells with these capabilities
We are usually talking about creating some
of the building blocks for life
But the trick is not only building those
things, but building them in an atmosphere
and environment that they can survive in
and eventually come together to create life
The classic experiment for creating life in the
lab is the Miller-Urey experiment (we will
start here and then move onto more modern
theories on the origins of life)
Miller-Urey Ingredients
- Methane
- Ammonia
- Hydrogen
- Water vapor
They excluded oxygen inside the atmosphere
to prevent oxidation and breaking down or
whatever was created
They were able to make a few amino acids
with the experiment
Note also that the other products made in
the process were toxic to life
One vital thing to the experiment was no
oxygen in the atmosphere
If there’s no oxygen there’s no ozone, which
means no protection from UV
But if you add oxygen to the equation it will
break down whatever is created
Dr. A. J. Monty White
“So the dilemma facing the evolutionist can
be summed up this way: amino acids would
not form in an atmosphere with oxygen and
amino acids would be destroyed in an
atmosphere without oxygen.”
Many other problems exist
Just because you have amino acids does not
mean that you get all the proteins needed
for life to exist
We need the amino acids to bind in a very
specific way (peptide bonds), and there are
several chemical bonds they could form with
each other that would make life impossible
The average protein (polypeptide chain) has
around 400 amino acids
The other problem is this happening inside
water, because water and hydrolysis tends to
break bonds, not form them
Because there were many problems with this
experiment people have put together other
experiments and theories to try to explain
the origins of life from non living material
Hydrothermal vent theory
Researchers in Japan claim life can start on
submarine hydrothermal vents deep inside
the ocean because of the high temperatures
in the environment that allow synthesis but
also can quickly cool in surrounding water
In the experiment they circulated 500 ml of a
strong solution of glycine (0.1 M) through a
chamber with high pressure
The first chamber was heated mainly to 200–
250 ° C; from there, the liquid was injected
at the rate of 8–12 ml/min into a cooling
chamber kept at 0 ° C.
In some of the runs, mild amounts of copper
were added to the solution, which was also
acidified to pH 2.5 by HCl at room temp
The results? Chains of Amino Acids
tetraglycine (yield 0.1%), hexaglycine (yield
0.001%) diketopiperazine (1%)
The team leader, Koichiro Matsuno said: “For
10 years, underwater hydrothermal vents
have been thought to be the place where life
began—and we were able to prove it.”
Did they show (like they claim) that life got
started (or could get started) with these
hydrothermal vents?
Problems:
The concentration of glycine of 0.1 M was far
higher than could be expected in a real
primordial soup
Another question would be where the amino
acid glycine came from to begin with
The longest polymer created was hexaglycine
(six long). Most enzymes though have
hundreds! And the hexaglycine produced was
found only in minuscule amounts.
Another problem was the experiment only
gave us homo-oligomer (all
monomers/amino acids are the same)
Living organisms are composed on 20
different amino acids, not just one
The last problem is that the exclusive ‘lefthandedness’ required for living things is
destroyed by heating. They didn’t test this
though because they used the simplest (and
only achiral) amino acid. (To be continued)
Venter’s experiment
The Guardian, had a
headline Craig Venter
creates synthetic life form
Many people have a false
understanding of this
What he did was create a strand of DNA from
scratch, and then placed it inside an already
existing cell. In an online video, he said the
following about the experiment:
“It’s pretty stunning when you just replace the
DNA software in the cell, and the cell instantly
starts reading that new software, starts
making a whole different set of proteins, and
within a short while, all the characteristics of
the first species disappear, and a new species
emerges from this software that controls that
cell going forward.”
No doubt this was quite the
accomplishment, but it wasn’t creating life in
the lab, it was reprogramming existing life
Some of the problems:
He used already existing machinery to read
his new strand of DNA, the problem is the
machine can’t get here without the DNA…
and the DNA is useless without the machine
When it came to the software, he obtained
the information from preexisting cells and
then modified it and then synthesized DNA
of his own (still very impressive, just not
creating life in the lab)
Venter used proteins from yeast in order to
help join things together
“The landmark achievement has yet to
occur,” McGee (of the Center for Practical
Bioethics in Kansas City, Mo) says. “What
they’ve done is they’ve successfully
transplanted DNA from one thing to another
without noticeably harming the operation of
the old DNA, as best they understand it, from
their definition of its function. When I put it
that way, it’s a hell of a lot less significant.”
“It’s a great feat, but I wouldn’t call it an
artificial organism,” Collins says [bioengineer
James Collins, a Howard Hughes Medical
Institute investigator at Boston University
who was not involved in the study]. Synthetic,
he contends, implies designed from scratch,
not plagiarized from a natural genome.
What’s more, the experiment required a
recipient cell to provide the cytoplasm to
hold the transplanted genome. “It’s small,
but it’s an important quibble,” he says.
RNA World
This is one of the most popular theory for the
origin of life, but has been adequately torn
apart by not just creationists
This theory says that RNA was the first form
of self replicating life here on planet earth
RNA has many features, like replication,
acting as an enzyme, and more that lead
people to believe it would come first
What is RNA?
For starters, it’s not a
simple molecule
These objections have been made:
1. RNA is too complex a molecule to have
arisen prebiotically
As we just saw, it’s not a simple arrangement
of pieces that come together
2. RNA is inherently unstable
Due primarily to oxygen RNA is unstable and
is reactive (DNA is stable because it lacks an
oxygen on the Carbon ring that RNA has)
3. There is no evidence that these molecules
needed for RNA (sugar, nitrogen base,
phosphate) would even be present in the
ancient earth (oceans) at this time
4. Sugars and bases must connect and
nucleosides must form with the N-bases
There is no know way for this uphill reaction
to occur for purine nucleosides in water, or
for pyrimidine nucleosides in any
environment (water or dry)
5. The environment must have been suitable
with the correct pH levels and temperature
There have been many other objections
raised to this theory, but we don’t have time
to cover them all
One evolutionist laid out 19 steps (problems)
that must be overcome for RNA world
While many consider it the best theory still,
they typically admit there are many problems
Cairns-Smith’s clay mineral theory
Because of many problems with the
“primordial soup” idea that most theories
utilize, some have suggested that life started
not in this primordial soup, but clay.
This theory says over time chemicals
produced in the clay from sunlight came
together in some sort of hypothetical self
replication molecules (that eventually evolve
to life today)
They argue only clay has the two essential
properties necessary for life, which is the
capacity to store and transfer energy
Along with this some clays can act as
catalysts, which is used as further evidence
That being said, the clay theory has it’s set of
problems that have caused most
evolutionary scientists to shy away from it
When we look at Miller’s experiment, and
the idea of primordial soup producing
amino acids as the building blocks for life,
he actually did that (even if it had problems)
This theory is lacking experimental evidence
for it, they haven’t showed building blocks
for life arise in clays
Another problem is the organic compounds
get so attached to the clay that they can’t
undergo any further chemical reactions
Other theories do exist for the origin of life
that we do not have time to cover
These are many of the popular views out
there today, although many of the authors
admit that they haven’t solved the problem
We will finish by looking at what may be the
most significant problem for these theories,
that we mentioned briefly early
This problem applies to all theories
Molecular Chirality
Many of the molecules that are required for
life to exist come in two forms
These two forms are non superimpossable
mirror images of one another
That means that they are related in the
same way that our right and left hands are
That’s why it’s called chirality, from the
Greek word for hand
These two different forms are called
enantiomers (opposite) or optical isomers,
because they will rotate plane (polarized)
light either to the right or to the left
Here is an
example of a
molecule that
is Chiral and
can’t be
superimposed
on itself
All amino acids, with
the exception of
glycine (the one used
in that experiment
earlier that we talked
about) are Chiral
Almost all biological polymers must by
homochiral, meaning all the same sidedness
Another term used is optically pure or 100 %
optically active
All amino acids in proteins are ‘left-handed’,
while all sugars in DNA and RNA, and in
metabolic pathways, are ‘right-handed’.
If you have a 50/50 mixture of left- and righthanded forms it’s called racemate or
racemic mixture
Racemic polypeptides (amino acid chains)
can’t form correct shapes unless they are all
uniform on handedness
Likewise, DNA cannot exist in the double
helix if one building block is off
So what’s the big problem?
Look what this organic chemistry text book
says on the topic
“Synthesis of chiral compounds from achiral
reagents always yields the racemic
modification.’ and ‘Optically inactive
reagents yield optically inactive products.”
When you form chiral molecules from achiral
material, you get a 50/50 left-right ratio
The question is, how did these different chiral
forms get separated to allow life to start?
The odds of getting just right or just lend
handed in the early formation of life by
random chance is statistically insane
(no one disagrees)
For a small protein (100 amino acids) it’s
10^-30 of getting it correct
That’s the probability for ANY homochiral
polypeptide (of that size) to create a
functional polypeptide with a specific
arrangement of amino acids is much lower
There have been methods put forward to try
to solve this problem, but most evolutionists
recognize that the problem is far from solved
Any theory that attempts to explain the
origins of life has to account for Chirality
Wrapping things up
[Attributing the origin of life to spontaneous
generation.] However improbable we regard
this event, it will almost certainly happen at
least once…. The time… is of the order of
two billion years.… Given so much time, the
“impossible” becomes possible, the possible
probable, and the probable virtually certain.
One only has to wait: time itself performs
the miracles.” — George Wald - In 'The Origin of
Life', Scientific American (Aug 1964), 191, 46.
Does adding time solve the problem?
This whole idea of hiding in time is utilized
by evolutionists all the time
This mindset would say that eventually those
100 left handed amino acids would come
together in a protein
Here is a way to understand this… The odds
of getting the correct handed amino acids
randomly together (100 of them) is the same
as flipping a coin and getting heads 100x
Eventually it will happen, right?
Chances are: 1 in
10,000,000000,000,000,000,000,000,000,000
If you flipped a coin once each second 24
hours a day, it would take 40 billion times
the “accepted” age of the universe (13.75
billion years) to get that result!
Time does not make all your problems go
away, some things will never happen
What if they successfully created life in the
laboratory? What would it prove?
Because of the problems explaining life
evolving here on planet earth, many have
suggested that it came from space
This would be (normally) in the form of a
bacteria on an asteroid that hits planet earth
They try to push the problem to a different
planet, and then they’ll make the excuse
that we don’t know what the planet is like so
it’s possible life can start there
Memory Verse
John 1:3: “All things were made through
him, and without him was not any thing
made that was made.”
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