This image represents a complex apparatus such as might have been used in the Miller Urey experiment.
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The Miller Urey Experiment
In the 1950's, biochemists Stanley Miller and
Harold Urey, conducted an experiment which demonstrated that several
organic compounds, including amino acids, could be formed spontaneously by
simulating the conditions of Earth's early atmosphere
They designed an
apparatus which held a mix of gases similar to those found in Earth's
early atmosphere over a pool of water, representing the primeval sea.
Electrodes delivered an electric current, simulating lightning, into the
gas-filled chamber. After allowing the experiment to run for one week,
they analyzed the contents of the liquid pool. They found that several
organic amino acids had formed spontaneously from inorganic raw materials
including water, ammonia, and methane. The equation for the combination of elements is shown below.
Their experiment (with different reactions) still holds if the Earth's initial atmosphere was not reducing but contained significant amounts of CO2
. These molecules collected together in the pool of water to form coacervates
Their experiments, along with considerable geological, biological, and
chemical evidence, lends support to the theory that the first life forms
arose spontaneously through chemical evolution. However, there are still
many skeptics of this theory who remain unconvinced.
British astrophysicist, Fred Hoyle, compares the likelihood of life
appearing on Earth by chemical evolution "as equivalent to the
possibility that a tornado sweeping through a junkyard might assemble a
Boeing 747 from the materials therein".
Shop Windows to the Universe Science Store!Traveling Nitrogen
is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.
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