S.L Miller conducted an experiment in 1953 to support the

Options

A. Theory of spontaneous generation.
B. Biogenesis
C. Chemical evolution of life
D. Natural selection.

Answer

**Step-by-Step Solution:**

1. **Identify the Experiment**: S.L. Miller conducted an experiment in 1953 that aimed to investigate the origins of life on Earth.

2. **Understand the Context**: The experiment was designed to simulate the conditions of primitive Earth. Miller, along with his mentor Harold Urey, sought to understand how organic compounds could form from inorganic substances.

3. **Conditions Used in the Experiment**: The experiment utilized a mixture of gases that were believed to be present in the early atmosphere of Earth. These included methane (CH₄), ammonia (NH₃), hydrogen (H₂), and water vapor (H₂O).

4. **Experimental Setup**: Miller created an apparatus that allowed these gases to be exposed to electric sparks, simulating lightning, which was thought to be a common occurrence on early Earth. The temperature was maintained at around 8000 degrees Celsius.

5. **Results of the Experiment**: After running the experiment for a week, Miller analyzed the contents of the apparatus and found that several organic compounds had formed, including amino acids, which are the building blocks of proteins.

6. **Conclusion**: The results of Miller's experiment supported the theory of chemical evolution, which posits that life originated from simple organic compounds that formed under prebiotic conditions. This experiment provided evidence for the idea that life could arise from non-living chemical processes.

7. **Rejection of Other Theories**: The experiment did not support the theory of spontaneous generation, which suggests that life can arise from non-living matter without any chemical processes. It also did not support biogenesis, which states that life arises from existing life, nor did it directly support Darwin's theory of natural selection.

**Final Answer**: S.L. Miller conducted an experiment in 1953 to support the theory of chemical evolution of life.

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