Sponges have a body plan named as ………… .

Explanation

**Step-by-Step Solution:**

1. **Understanding Sponges**: Sponges are simple, multicellular organisms that belong to the phylum Porifera. They are considered some of the most primitive animals.

2. **Identifying the Body Plan**: The body plan of sponges is characterized by a unique arrangement of cells rather than tissues or organs. This is a key feature that distinguishes them from more complex animals.

3. **Defining the Body Plan**: The specific name for the body plan found in sponges is the "Cell Aggregate Plan." This term reflects the organization of sponges, where the body is composed of a cluster of cells.

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