Regeneration was first discovered in Hydra by

Options

A. Linnaeus
B. Trembley
C. Thomas Addison
D. Stanley

Answer

**Step-by-Step Solution:**

1. **Understanding Regeneration**: Regeneration is the biological process by which organisms can replace or restore lost or damaged body parts. This involves the formation of new tissues and cells.

2. **Identifying Organisms that Regenerate**: Various organisms exhibit regeneration, including certain plants and animals. Notably, Hydra and Planaria (flatworms) are well-known examples.

3. **Historical Context**: The question asks about the discovery of regeneration specifically in Hydra.

4. **Key Scientist**: The scientist who first discovered the process of regeneration in Hydra is Tremblay.

5. **Experiment Conducted**: Tremblay conducted an experiment where he cut a Hydra in half. He observed that the two halves eventually developed into two complete Hydras.

6. **Conclusion**: Tremblay concluded that this regenerative ability was a unique characteristic of Hydra, which is part of the phylum Cnidaria (formerly known as Coelenterata) and is commonly referred to as a freshwater polyp.

7. **Final Answer**: Therefore, the correct answer to the question is that regeneration was first discovered in Hydra by Tremblay.

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