What did S.L. Miller observe in his experimental set-up?

Options

A. Formation of sugars and nitrogenous bases
B. Formation of amino acids
C. Formation of pigments
D. Formation of fats.

Answer

**Step-by-Step Solution:**

1. **Understanding S.L. Miller's Experiment**: S.L. Miller conducted an experiment in 1953 to simulate the conditions of the early Earth to investigate the origin of life.

2. **Setting Up the Experiment**: Miller created a closed system that mimicked the primitive atmosphere of Earth, which included gases such as methane (CH4), ammonia (NH3), hydrogen (H2), and water vapor (H2O).

3. **Simulating Environmental Conditions**: He applied electrical sparks to the mixture of gases to simulate lightning, which was thought to be a common occurrence in the early atmosphere.

4. **Observation of Results**: After running the experiment for a week, Miller analyzed the contents of the flask and observed the formation of several organic compounds.

5. **Key Observation**: The most significant finding was the formation of amino acids, which are the building blocks of proteins.

6. **Conclusion**: Miller's experiment provided evidence that organic compounds necessary for life could be synthesized from inorganic precursors under conditions thought to be similar to those of the early Earth.

**Final Answer**: S.L. Miller observed the formation of amino acids in his experimental setup.

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