Water currents in a sponge body are maintained by

Options

A. archaeocytes
B. pinacocytes
C. spongocytes
D. choanocytes

Answer

To answer the question "Water currents in a sponge body are maintained by," we will analyze the different cell types found in sponges and their functions step by step.

### Step-by-Step Solution:

1. **Understanding Sponge Structure**:
- Sponges have a simple body structure with different types of cells that perform various functions.

2. **Identifying Cell Types**:
- The question provides four options: archiocyte, pinacocyte, spongyocyte, and choanocyte.

3. **Analyzing Each Cell Type**:
- **Archiocyte**: These cells are involved in reproduction as they can differentiate into gametes (ova and sperm). They do not maintain water currents.
- **Pinacocyte**: These cells form the outer layer of the sponge, known as the pinacoderm. They provide protection but are not responsible for water currents.
- **Spongyocyte**: These cells contribute to the formation of the sponge's skeleton. They help in structural support but do not maintain water currents.
- **Choanocyte**: Also known as collar cells, these are located in the inner layer of the sponge (the choanoderm). They have flagella that create water currents, facilitating the flow of water through the sponge's body.

4. **Conclusion**:
- The cells responsible for maintaining water currents in a sponge are the choanocytes. Therefore, the correct answer is **choanocyte**.

### Final Answer:
Water currents in a sponge body are maintained by **choanocytes**.

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