Which one of the following statements is not correct?

Options

A. Retinal is a derivative of vitamin C
B. Rhodopsin is a purplish red protein present in rods only
C. Retinal is the light absorbing protein of visual photopigment
D. In retina, the rods have the photopigment rhodopsin, while cones have three different photopigments

Answer

To solve the question, "Which one of the following statements is not correct?", we need to analyze the statements provided and determine which one is incorrect.

### Step-by-Step Solution:

1. **Identify the Statements**:
- Statement 1: "Ratingal is a derivative of vitamin C."
- Statement 2: "Rodopsy is a purplish red protein present in rods only."
- Statement 3: "Ratingal is a light absorbing protein of visual photopigments."
- Statement 4: "Rodopsy and Y-O-N have three different photopigments."

2. **Evaluate Each Statement**:
- **Statement 1**: "Ratingal is a derivative of vitamin C."
- This statement is incorrect. Ratingal (or Retinal) is actually a derivative of vitamin A, not vitamin C.

- **Statement 2**: "Rodopsy is a purplish red protein present in rods only."
- This statement is correct. Rodopsy (or Rhodopsin) is indeed a protein found in the rod cells of the retina, which is responsible for vision in low light conditions.

- **Statement 3**: "Ratingal is a light absorbing protein of visual photopigments."
- This statement is also correct. Ratingal (Retinal) plays a crucial role in the phototransduction process, absorbing light and enabling vision.

- **Statement 4**: "Rodopsy and Y-O-N have three different photopigments."
- This statement is correct. Rodopsy (Rhodopsin) and other photopigments in the eye (like Iodopsin) are involved in color vision and light detection.

3. **Conclusion**:
- The incorrect statement is **Statement 1**: "Ratingal is a derivative of vitamin C."

### Final Answer:
The statement that is not correct is **Statement 1**: "Ratingal is a derivative of vitamin C."

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