Fish are able to see under water because

Options

A. Both lens and cornea are spherical
B. Cornea is pherical, lens is flat
C. Cornea is flat , lens is spherical
D. Both lens and cornea are flat.

Answer

**Step-by-Step Solution:**

1. **Understanding the Problem**: The question asks why fish are able to see underwater, which involves understanding the anatomy of fish eyes compared to human eyes.

2. **Comparing Human and Fish Vision**: Humans have difficulty seeing underwater due to the scattering of light, which causes blurred vision. This is because the human eye is not optimized for underwater vision.

3. **Anatomy of Fish Eyes**: Fish eyes are adapted for underwater vision. The key components to focus on are the lens and cornea of the fish's eye.

4. **Characteristics of the Fish Lens**: The lens of a fish's eye is described as being almost spherical and extremely convex. This shape helps in focusing light effectively.

5. **Characteristics of the Fish Cornea**: In contrast, the cornea of fish is flat. This difference in shape between the lens and cornea is crucial for their ability to see clearly underwater.

6. **Refractive Index**: The refractive index of the lens in fish is very high, which means it can bend light effectively. This allows the lens to focus light rays directly onto the retina.

7. **Conclusion**: Due to the combination of a spherical lens and a flat cornea, fish can focus light correctly on their retina, allowing them to see clearly underwater.

8. **Final Answer**: Therefore, the correct answer to the question is that fish are able to see underwater because their cornea is flat and their lens is spherical.

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