The functional units of compound eye of an insect are called

Options

A. Fenestrae
B. Ocelli
C. Radula
D. Ommatidia

Answer

**Step-by-Step Text Solution:**

1. **Understanding Compound Eyes**: Insects, including cockroaches, possess compound eyes, which are made up of multiple smaller units. These compound eyes are located on each side of the head and are responsible for a wide field of vision.

2. **Structure of Compound Eyes**: Each compound eye is large and has a distinctive shape. In the case of cockroaches, the eyes are kidney-shaped and black in color.

3. **Facets of Compound Eyes**: The compound eye consists of numerous small units called facets. In cockroaches, there are approximately 2000 facets in each compound eye. These facets are transparent and have a hexagonal, biconvex shape.

4. **Functional Units**: Each facet of the compound eye corresponds to a visual element known as an ommatidium. The ommatidia are the functional units of the compound eye, responsible for capturing light and contributing to the insect's vision.

5. **Conclusion**: Therefore, the functional units of the compound eye of an insect are called **ommatidia**.

**Final Answer**: Ommatidia

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