Question

Choose the correct sequence during formation of chemicals on early earth

• A. Ammonia, Nucleic acid, Proteins, Carbohydrates
• B. Ammonia, Water, Nucleic acid, Protein
• C. Proteins, Carbohydrate, Water, Nucleic acid
• D. Ammonia, Proteins, Carbohydrates, Nucleic acid

Answer 1

The correct option is D Ammonia, Proteins, Carbohydrates, Nucleic acid

Atomic phase
Primitive earth had a large number of atoms like hydrogen, carbon, oxygen, nitrogen, phosphorus etc. The amount of oxygen was less and therefore the atmosphere was reducing in nature.

Formation of simple molecules
Hydrogen atoms were most abundant and combined with oxygen to form water and with nitrogen to form ammonia.

Formation of simple organic molecules
Simple molecules like methane, ammonia, carbon dioxide, water and hydrogen cyanide led to the formation of simple organic molecules like amino acids, sugars, purines, pyrimidines, fatty acids etc.

Formation of complex organic molecules
Simple organic molecules like amino acids, sugars, purines, pyrimidines, fatty acids etc combined to form polymers like proteins, carbohydrates, nucleic acids, fats. The energy for the reactions came from the sun, lightning, and electric discharge. These macromolecules aggregated to form prebiont from which the first living cell arose.

Chemical evolution
During the chemical evolution ammonia appeared first followed by proteins, carbohydrates and then nucleic acid.

Final answer
(b) Ammonia, Proteins, Carbohydrates, Nucleic acid