What are gemmules?

Explanation

**Step-by-Step Solution:**

1. **Definition of Gemmules**: Gemmules are specialized structures found in sponges, specifically within the phylum Porifera. They serve as a means of asexual reproduction.

2. **Function of Gemmules**: The primary function of gemmules is to facilitate both survival and reproduction. They allow sponges to endure unfavorable environmental conditions.

3. **Asexual Reproduction**: Gemmules are considered asexual reproductive organs. This means they can produce new organisms without the need for fertilization.

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