Fibrous bands develop in the cells of anther wall layer known as

Options

A. Epidermis
B. Endothecium
C. Middle layers
D. Tapetum.

Answer

To answer the question about which layer of the anther wall develops fibrous bands, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Anther**:
- The anther is a part of the stamen in flowering plants and consists of four layers: epidermis, endothecium, middle layer, and tapetum.

2. **Identify the Function of Each Layer**:
- **Epidermis**: This is the outermost layer that provides protection.
- **Endothecium**: This layer is located beneath the epidermis and is crucial for the dehiscence (opening) of the anther.
- **Middle Layer**: This layer is situated between the endothecium and the tapetum and has a supportive role.
- **Tapetum**: This is the innermost layer that nourishes the developing pollen grains.

3. **Focus on the Endothecium**:
- The endothecium is known to develop fibrous bands or thickened portions, which are primarily made of callose. These fibrous bands help in the dehiscence of the anther, facilitating the release of pollen.

4. **Conclusion**:
- Based on the information about the layers of the anther and their functions, the fibrous bands develop in the cells of the anther wall layer known as the **endothecium**.

### Final Answer:
The fibrous bands develop in the cells of the anther wall layer known as **endothecium**.

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