Miller and Urey conducted an experiment in 1953 to test the Oparin-Haldane theory that organic molecules could have formed on the early Earth. They placed water, methane, ammonia and hydrogen gases in an apparatus and provided electrical sparks as an energy source to simulate lightning. After one week, they detected amino acids such as glycine and alanine in the solution, supporting the idea that simple organic compounds could have been produced by chemical reactions in the early Earth's atmosphere.

1. MILLER UREY
EXPERIMENT

2. INTRODUCTION
The only thing that goes up and never
down is time or age. With time and age,
many things change including new
constructions, modification as needed to be
fittest, destruction of unfit ones and even
extinction. All these things are under
evolution.
Oparin – Haldane Theory was the first
widely accepted scientific theory of organic
evolution. Miller – Urey theory is a proof for
above theory.

3. Given by :- A. I. Oparin (1924) & J. B. S. Haldane
(1929).
Supported by :- Miller & Urey – 1953.
Phases of organic evolution as per this theory :-
The cosmos
The primitive earth
The atomic phase
Cooling of earth
Origin of molecules and simple compounds
Origin of organic compounds
Origin of Coacervates
Origin of First living cell or protovirus
Origin and modifications of Monerans
Evolution of Protistans and autotrophism
Evolution of Fungi, plantae and animalia

4. APPARATUS SET UP IN M – U EXPERIMENT

5. MILLER – UREY EXPERIMENT
Proposed by :- Stanley Miller & Harold
C. Urey – 1953.
Aim – To demonstrate Oparin –
Haldane Theory or synthesis of
macromolecules in primitive earth.
Apparatus Taken – Discharge chamber,
electrodes and electrical discharge
system, condenser, steam chamber,
pipes, stop cocks, vacuum tubes.

6. Gases Taken – Hydrogen, water vapour,
ammonia, methane.
Arrangement – All apparatus arranged as
per diagram and gases and water put
accordingly.
Procedure
All gases were kept in discharge chamber
and steam chamber ensured continuous
supply of water vapour.
Energy was provided by heavy electrical
discharges in the discharge chamber as
that from lightning and thunder.

7. This process continued for a week and
samples were taken from the U – shaped
part.
Observations – It was condensed dark red
solution having amino acids as glycine,
alanine, aspartic acid & glutamic acid,
many other organic compounds and gases
like CO, CO2.

8. In primitive earth, organic compounds
might have been formed by Abiogenesis
due to absence of oxygen which may be
hampered by oxygen.
They might have accumulated forming
prebiotic soup.
The soup might have given rise to complex
organic compounds.
CONCLUSION