Question

The visible coloured ring of the eye is called:

• A. \( \text{Lens} \)
• B. \( \text{Retina} \)
• C. \( \text{Cornea} \)
• D. \( \text{Iris} \)

Hint:

The color of the iris is determined by the amount and type of pigment (melanin) it contains. It varies among individuals and can range from brown to blue, green, or gray.

Answer 1

The Correct Option is D

Step 1: Understanding the anatomy of the eye. The iris is the colored, circular structure in the eye that surrounds the pupil. It controls the amount of light entering the eye by adjusting the size of the pupil. 

Step 2: Comparison with other options. - Option \( (A) \): The lens is a transparent, biconvex structure behind the iris that focuses light onto the retina. 
- Option \( (B) \): The retina is the light-sensitive layer at the back of the eye responsible for converting light into neural signals. 
- Option \( (C) \): The cornea is the clear, dome-shaped surface that covers the front of the eye and refracts light. 

Conclusion. The visible colored part of the eye is the iris, making \( (D) \) the correct answer.

Answer 2

This question asks for the name of the visible colored ring that gives eyes their color. Working through the main visible structures of the eye helps rule out the ones that do not match this description.

1. Lens: The lens sits behind the iris and is a clear, flexible structure that bends light onto the retina. It is transparent, not colored, and cannot be seen from outside the eye.
2. Retina: The retina lines the inside back wall of the eye and converts light into nerve signals. It is completely hidden from outside view and has no visible color of its own.
3. Cornea: The cornea is the clear, curved front window of the eye that lets light in. It is transparent, so while it covers the colored ring, it does not itself carry any color.
4. Iris: The iris is the ring-shaped, pigmented structure sitting just behind the cornea and in front of the lens. Its pigment gives the eye its blue, brown, green, or hazel color, and it also controls pupil size to regulate how much light enters.

Among the four structures, only the iris is both visible from outside and colored, since the cornea and lens are clear and the retina is hidden inside the eyeball.

Therefore, the correct answer is Iris.