Oparin of Russia and Haldane of England proposed that the first form of life could have come from preexisting non-living organic molecules (eg. RNA, protein etc) and that formation of life was preceded by

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the proposal made by Oparin and Haldane regarding the origin of life and what preceded the formation of life.

2. **Identifying Key Concepts**: Oparin and Haldane suggested that the first forms of life originated from pre-existing non-living organic molecules, such as RNA and proteins.

3. **Explaining the Process**: The formation of these organic molecules was believed to have come from inorganic molecules. This means that before life could exist, there had to be a process that transformed inorganic substances into organic compounds.

4. **Describing the Early Earth Conditions**: Early Earth had high temperatures and a dense atmosphere rich in gases like methane and ammonia. These conditions were conducive to the formation of organic molecules from inorganic precursors.

5. **Chemical Evolution**: The transformation of inorganic molecules into organic molecules is referred to as "chemical evolution." This process is crucial as it sets the stage for the emergence of life.

6. **Conclusion**: Therefore, the formation of life was preceded by chemical evolution, which involved the synthesis of organic molecules from inorganic compounds.

**Final Answer**: The formation of life was preceded by **chemical evolution**.

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