The Human Eye is a sense organ that reacts to light and allows vision.The human eye can differentiate between about 10 million colors and is possibly capable of detecting a single photon. The eye is part of the sensory nervous system. It consists of two types of cells – Rod cells & Cone cells.
Structure of Human Eye –
- The eye is not shaped like a perfect sphere, rather it is a fused two-piece unit, composed of an anterior (front) segment and the posterior (back) segment.
- There are two eyes, situated on the left and the right of the face. They sit in two bony cavities called the orbits, which are present in the skull.
- Six extraocular muscles attach directly to the eyes to assist with movement. The front visible part of the eye is made up of the whitish sclera, a coloured iris, and the pupil.
- The front part is also called the anterior segment of the eye.The cornea is transparent and more curved, & is linked to retina and the outer white shell called the sclera.
- The cornea and sclera are connected by an area termed the limbus. The iris is the pigmented circular structure concentrically surrounding the center of the eye, the pupil, which appears to be black.