Which of the following results in the generation of potential differences in the photoreceptor cells of eyes ?

Options

A. Conversion of retinal into opsin
B. Conversion of opsin into retinal
C. Dissociation of the retianl from opsin
D. Dissociation of the opsin from retinol

Answer

### Step-by-Step Solution:

1. **Understanding Photoreceptor Cells**: Photoreceptor cells in the eye, namely rods and cones, are responsible for converting light into electrical signals. They contain light-sensitive pigments that play a crucial role in this process.

2. **Identifying the Pigments**: The main pigment in rod cells is called rhodopsin, which is composed of two components: retinal (a derivative of vitamin A) and opsin (a protein).

3. **Mechanism of Light Detection**: When light (specifically, photons) hits the photoreceptor cells, it interacts with the rhodopsin pigment. This interaction causes a change in the structure of the retinal.

4. **Dissociation of Retinal and Opsin**: The light energy causes the weak bond between retinal and opsin to break. This process is known as the dissociation of retinal from opsin.

5. **Generation of Potential Difference**: The breaking of the bond between retinal and opsin leads to a change in the electrical state of the photoreceptor cell, generating a potential difference. This potential difference is crucial for the transmission of visual signals to the brain.

6. **Conclusion**: Therefore, the correct answer to the question is that the dissociation of retinal from opsin results in the generation of potential differences in the photoreceptor cells of the eyes.

### Final Answer:
The dissociation of retinal from opsin.

---