Explain the functions of various parts of a human eye.
Asked by Rupal Sinha
| 6th Dec, 2013,
08:47: PM
Structure of human eye
The human eye is roughly spherical in shape with diameter of about 2.3 cm. It consists of a convex lens made up of living tissues. Hence, human lenses are living organs contrary to the simple optical lenses.
The white of the eye is known as the sclera . It is the tough, opaque tissue that protects the outer layer of the eye. Iris is the coloured part of the eye, and the pupil is the black,
The main parts of the human eye and their respective functions are:
Sr. No.
Human eye part
Function
1.
Pupil
Opens and closes in order to regulate and control the amount of light
2.
Iris
Controls light level similar to the aperture of a camera
3.
Sclera
Protective outer coat
4.
Cornea
Thin membrane which provides 67% of the eye’s focusing power
5.
Crystalline lens
Helps to focus light into the retina
6.
Conjunctiva
Covers the outer surface (visible part) of the eye
7.
Aqueous humour
Provides power to the cornea
8.
Vitreous humour
Provides the eye its form and shape
9.
Retina
Captures the light rays focussed by the lens and sends impulses to the brain via optic nerve
10.
Optic nerve
Transmits electrical signals to the brain
11.
Ciliary muscles
Contracts and extends in order to change the lens shape for focusing.
12. Eye Lids Eye lids are provided to control the amount of light falling on the
eye. They also protect the eye from dust particles etc.
Structure of human eye
The human eye is roughly spherical in shape with diameter of about 2.3 cm. It consists of a convex lens made up of living tissues. Hence, human lenses are living organs contrary to the simple optical lenses.
The white of the eye is known as the sclera . It is the tough, opaque tissue that protects the outer layer of the eye. Iris is the coloured part of the eye, and the pupil is the black,
The main parts of the human eye and their respective functions are:
Sr. No. |
Human eye part |
Function |
1. |
Pupil |
Opens and closes in order to regulate and control the amount of light |
2. |
Iris |
Controls light level similar to the aperture of a camera |
3. |
Sclera |
Protective outer coat |
4. |
Cornea |
Thin membrane which provides 67% of the eye’s focusing power |
5. |
Crystalline lens |
Helps to focus light into the retina |
6. |
Conjunctiva |
Covers the outer surface (visible part) of the eye |
7. |
Aqueous humour |
Provides power to the cornea |
8. |
Vitreous humour |
Provides the eye its form and shape |
9. |
Retina |
Captures the light rays focussed by the lens and sends impulses to the brain via optic nerve |
10. |
Optic nerve |
Transmits electrical signals to the brain |
11. |
Ciliary muscles |
Contracts and extends in order to change the lens shape for focusing. |
Answered by Faiza Lambe
| 7th Dec, 2013,
10:09: AM
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Sign Up
Verify mobile number
Enter the OTP sent to your number
Change