The colour differentiation is done by

Options

A. Rods
B. Cones
C. Bipolar nerve cells
D. Pigmented epithelium.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the mechanism or structure responsible for color differentiation in the human eye.

2. **Understand the Options**: The options provided are:
- Rhodopsin
- Cones
- Bipolar nerve cells
- Pigmented epithelium

3. **Analyze the Photoreceptor Cells**: The retina contains two main types of photoreceptor cells: rods and cones.
- **Rods**: These cells are responsible for vision in low light conditions (scotopic vision) and contain the pigment rhodopsin. They do not contribute to color vision.
- **Cones**: These cells are responsible for color vision and function best in bright light (photopic vision). They contain different pigments such as erythrolabe (red), chlorolabe (green), and cyanolabe (blue), which allow for the perception of color.

4. **Evaluate Other Options**:
- **Bipolar Nerve Cells**: These cells are involved in transmitting signals from photoreceptors to ganglion cells but do not directly contribute to color differentiation.
- **Pigmented Epithelium**: This layer absorbs excess light and prevents scattering but does not participate in color differentiation.

5. **Conclusion**: Since cones are the photoreceptor cells responsible for color vision, the correct answer to the question is "cones."

**Final Answer**: The color differentiation is done by **cones**.

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