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
Oparin – Haldane Theory was the first
widely accepted scientific theory of organic
evolution. Miller – Urey theory is a proof for
3. Given by :- A. I. Oparin (1924) & J. B. S. Haldane
Supported by :- Miller & Urey – 1953.
Phases of organic evolution as per this theory :-
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
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,
Arrangement – All apparatus arranged as
per diagram and gases and water put
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
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
The soup might have given rise to complex