In 1953, S.L. miller, an American scientist, created electric discharge in closed flask containing which gases at `800^(@)C`.

Options

A. Fatty acids
B. Proteins
C. Carbohydrates
D. Amino acids

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist and Year**: The question mentions S.L. Miller, an American scientist, and the year 1953. This sets the context for the experiment being referred to.

2. **Understand the Experiment**: Miller conducted an experiment to simulate the conditions of early Earth. He created an electric discharge in a closed flask.

3. **Determine the Gases Used**: The gases present in the closed flask during Miller's experiment were:
- Methane (CH₄)
- Hydrogen (H₂)
- Ammonia (NH₃)
- Water vapor (H₂O)

4. **Temperature of the Experiment**: The experiment was conducted at a high temperature of 800°C, which was meant to mimic the conditions of the early Earth.

5. **Outcome of the Experiment**: The electric discharge in the presence of these gases led to the formation of organic compounds, specifically amino acids.

6. **Significance of the Findings**: The results of Miller's experiment provided evidence for the theory of abiogenesis, suggesting that life could arise from non-living molecules through natural processes.

7. **Conclusion**: Based on the gases used in Miller's experiment and the outcome, the correct answer to the question is that the flask contained gases that led to the formation of amino acids.

**Final Answer**: The gases used in the closed flask by S.L. Miller at 800°C were methane, hydrogen, ammonia, and water vapor, leading to the formation of amino acids.

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