Louis Pasteur's view on the origin of life is that

Options

A. They have arisen from nucleic acid and protein found in primitive soup
B. They arose from bacteria as a result of loss of cell wall ribosomes, ect.
C. They arose from some bacteria which developed a nucleus only
D. They are modified plasmide which are in fact the fragments of nucleic acids of the host.

Answer

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

1. **Understanding Louis Pasteur's Contribution**: Louis Pasteur was a prominent French scientist known for his work in microbiology and his experiments that challenged the idea of spontaneous generation. He is famous for demonstrating that life does not arise spontaneously from non-living matter.

2. **The Swan Neck Flask Experiment**: Pasteur conducted the Swan Neck Flask Experiment to prove that microorganisms in the air were responsible for contamination and that life comes from pre-existing life. He used flasks with curved necks that allowed air in but prevented dust and microbes from entering.

3. **Conclusion from the Experiment**: The results of the experiment showed that when the flasks were sterilized and left open, they remained free of microbial growth. This led to the conclusion that life comes from existing life, not from non-living matter.

4. **Evaluating the Options**:
- **Option 1**: "They have arisen from nucleic acid and protein found in primitive soup." This option suggests a form of abiogenesis, which is not aligned with Pasteur's findings.
- **Option 2**: "They arose from the bacteria as a result of loss of cell wall, ribosome, etc." This is incorrect as it does not reflect Pasteur's views.
- **Option 3**: "They arose from some bacteria which develop a nucleus only." This is also incorrect and does not represent Pasteur's conclusions.
- **Option 4**: "They are modified plasmids which are in fact the fragments of nucleic acids of the host." This option is incorrect as it does not relate to Pasteur's work.

5. **Correct Answer**: Based on Pasteur's experiments and conclusions, none of the provided options accurately reflect his views on the origin of life. However, if we consider the essence of his work, the closest option would be option 1, but it still does not align with his assertion that life arises from pre-existing life.

**Final Answer**: Louis Pasteur's view on the origin of life is that life arises from pre-existing life, which is not accurately represented in the provided options.

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