Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYEvolution1 Mark
MCQ
Which of the following was present in primitive earth?
A
Ammonia and helium
B
Juvenile water vapour
C
Oxygen
✓
Hydrogen and methane
✓
Answer
Correct option: D.
Hydrogen and methane
The primitive earth is thought to be highly reducing in nature due to the absence of oxygen. Hydrogen and methane predominated the atmosphere and caused the condensation of various biomolecules. This theory was forwarded by Oparin and Haldane which accounts for the chemical evolution of life.
It was proved by Urey and Miller through an experimental set$-$up that mimicked the primitive earth conditions and resulted in the formation of amino acids.
Hence, the correct answer is 'Hydrogen and methane'.
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