Who said that "Life arises from pre-existing life"?

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the scientist who proposed that "life arises from pre-existing life." This concept is fundamental in biology and relates to the origins of life.

2. **Identifying Key Concepts**: The phrase "life arises from pre-existing life" suggests a rejection of spontaneous generation, which was a common belief before the 19th century. This principle indicates that living organisms come from other living organisms.

3. **Recalling Historical Figures**: One prominent scientist known for his work on this topic is Louis Pasteur. He conducted experiments that challenged the idea of spontaneous generation and supported the theory that life comes from existing life.

4. **Citing the Scientist and Explanation**: Louis Pasteur is the scientist who stated that "life arises from pre-existing life." He demonstrated this through various experiments, notably his swan-neck flask experiment, which showed that microorganisms in the air could contaminate sterile solutions, leading to the conclusion that life does not spontaneously generate.

5. **Final Answer**: Therefore, the answer to the question is Louis Pasteur.

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