In sponges the spicules are formed by

Options

A. Choanocytes
B. Chromocytes
C. Scleroblasts
D. porocytes

Answer

To answer the question "In sponges, the spicules are formed by," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Spicules**:
- Spicules are structural elements found in sponges. They provide support and protection to the sponge's body.
- They are made of inorganic materials such as silica or calcium carbonate.

2. **Identifying the Cell Types**:
- The question provides four options: A-quinocytes, B-chromocytes, C-scleroblasts, D-porocytes.
- We need to determine which of these cell types is responsible for the formation of spicules.

3. **Role of Scleroblasts**:
- Scleroblasts are specialized cells in sponges that are responsible for the synthesis of spicules.
- They secrete the materials (like silica or calcium carbonate) that form the spicules.

4. **Eliminating Other Options**:
- Quinocytes: These are not known for spicule formation.
- Chromocytes: These are involved in pigment production, not in forming spicules.
- Porocytes: These cells are responsible for forming the pores in sponges, not for spicule formation.

5. **Conclusion**:
- Based on the information, the correct answer is C - scleroblasts.

### Final Answer:
In sponges, the spicules are formed by **C - scleroblasts**.

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