According to Oparin, which one of the following was not present in the primitive atmosphere of the earth[2004]a)Methaneb)Oxygenc)Hydrogend)Water vapourCorrect answer is option 'B'. Can you explain this answer?

Question

Answer

Acc to oparin, oxygen is not present in the primitive atmosphere of earth

Answer

The absence of oxygen was the primary reason why the primitive atmosphere was reducing in nature. The BGA were the first organisms to evolve oxygen after which the oxygen revolution began. Today's atmosphere is an oxidising one.

Answer

According to Oparin's hypothesis, the primitive atmosphere of the Earth was composed of several gases, but oxygen was not present. This hypothesis is known as the 'primordial soup' theory and suggests that the Earth's early atmosphere was reducing in nature, meaning it lacked oxygen.

Explanation:
The primitive atmosphere of the Earth, according to Oparin's hypothesis, consisted of the following gases:

a) Methane: Methane (CH4) is a simple hydrocarbon that was believed to be present in the primitive atmosphere. Methane is produced by certain microorganisms and can be a source of energy for early life forms.

c) Hydrogen: Hydrogen (H2) was also believed to be present in the primitive atmosphere. It is the most abundant element in the universe and can react with other elements to form various compounds.

d) Water vapor: Water vapor (H2O) was another component of the primitive atmosphere. It is released during volcanic activity and can condense to form liquid water under suitable conditions.

However, option b) Oxygen was not present in the primitive atmosphere. This is because oxygen is a highly reactive gas and would have readily reacted with other compounds, making it unlikely to be present in its free form. Oxygen is believed to have accumulated in the atmosphere much later, as a result of photosynthetic activity by early cyanobacteria.

Oparin's hypothesis suggests that the primitive atmosphere was reducing, meaning it lacked oxygen but had an abundance of reducing gases like methane and hydrogen. This atmosphere provided favorable conditions for the formation of organic molecules, which eventually led to the development of life on Earth.

In summary, according to Oparin's hypothesis, the primitive atmosphere of the Earth did not contain oxygen (option b). The presence of other gases like methane, hydrogen, and water vapor provided the necessary conditions for the formation of organic molecules and the emergence of life.

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