Question

According to the theory of abiogenesis, primitive Earth’s atmosphere, devoid of life, consisted of a mixture of :

• A. oxygen, hydrogen, methane, ammonia
• B. water vapour, hydrogen, ammonia and methane
• C. ozone, oxygen and water vapour
• D. hydrogen, carbon dioxide, ammonia

Answer 1

The correct option is B water vapour, hydrogen, ammonia and methane

The theory of biochemical evolution or abiogenesis is the most accepted theory for origin of life on Earth. It proved that life originated from simple organic molecules. According to this theory, primitive Earth was devoid of oxygen and had a reducing atmosphere containing methane, ammonia, hydrogen and water vapour. These gases were believed to originate from volcanic outgassing and were very toxic. These conditions were replicated in the famous Miller’s experiment. In the high energy chambers of Miller’s set up, complex building blocks of life like amino acids and nucleic acids were formed, which proved the theory of abiogenesis.