The phenomenon of regeneration in sponges was observed and explained by

Options

A. john Ellis
B. Aristotle
C. H.W. Wilson
D. Robert E. Grant

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks about who observed and explained the phenomenon of regeneration in sponges.

2. **Identifying the Organism:** Sponges belong to the phylum Porifera, which are simple aquatic animals characterized by their porous bodies and cellular level of organization.

3. **Defining Regeneration:** Regeneration is the process by which organisms replace or restore lost or damaged cells, tissues, or organs. In sponges, this process occurs rapidly, especially in response to injury.

4. **Recognizing Key Contributors:** The question provides four options: John Ellis, Aristotle, H. W. Wilson, and Robert A. Grant. We need to identify which of these individuals is associated with the study of regeneration in sponges.

5. **Identifying the Correct Answer:** H. W. Wilson is credited with observing and explaining the regeneration process in sponges. He noted how wounded cells in sponges could be replaced rapidly through regeneration.

6. **Conclusion:** Based on the information gathered, the correct answer to the question is H. W. Wilson.

**Final Answer:** H. W. Wilson

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