a) The wall of the eye is made up of three layers namely outer sclera, the middle choroid and the inner retina. b) The sclerotic layer has a bulged, transparent portion called cornea. Cornea is protected by a thin membrane called conjunctiva. c) The choroid has an opening in the front in the centre called pupil. The pupil has tiny muscles arranged radially called iris. d) A transparent bi-convex lens is located behind the iris. The lens is held in position by ciliary muscles and suspensory ligaments. e) The area between the cornea and the lens is filled with a fluid called aqueous humour. f) The space between the cornea and the lens is filled with a thick fluid called vitreous humour. g) The inner retina layer contains receptor cells called rods and cones.