Humans have two eyes, situated on the left and the right of the face. The eyes sit in bony cavities called the orbits, in the skull. There are six extra ocular muscles that control eye movements. The front visible part of the eye is made up of the whitish scleroses , a coloured iris, and the pupil. A thin layer called the conjunctiva sits on top of this. The front part is also called the anterior segment of the 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. The anterior segment is made up of the cornea, iris, and lens. The cornea is transparent and more curved and is linked to the larger posterior segment, composed of the vitreous, retina, choroid, and the outer white shell called the scleroses. The cornea is typically about 11.5 mm (0.45 in) in diameter, and 0.5 mm (500 μm) in thickness near its centre. The posterior chamber constitutes the remaining five-sixths; its diameter is typically about 24 mm (0.94 in). The cornea and scleroses are connected by an area termed the limbs. The iris is the pigmented circular structure concentrically surrounding the centre of the eye, the pupil, which appears to be black. The size of the pupil, which controls the amount of light entering the eye, is adjusted by the iris' dilator and sphincter muscles.



Light energy enters the eye through the cornea, through the pupil, and then through the lens. The lens shape is changed for near focus (accommodation) and is controlled by the ancillary muscle. Photons of light falling on the light-sensitive cells of the retina (photo-receptor cones and rods) are converted into electrical signals that are transmitted to the brain by the optic nerve and interpreted as sight and vision.



Eye is located inside orbit. they are supported by extra ocular muscles. eye has different layers scleroses, cornea, choroid, retina. We discussed ANATOMY AND FUNCTIONS of different parts of eye.. Lens, iris, rods, cones, cilia body, cilia muscles, pupil, canal of schlemiel, Aqueous humour, vitreous humour infra-ocular pressure, glaucoma- open angle, closed angle