The retina is a layer of cells at the of the eye. The retina detects focused by the and the . The retina is connected to the by the optic nerve.

The cornea is a covering over the that helps the eye. Light as it passes through the cornea. The cornea begins bending light to make an ; the finishes the job.

The pupil is the circle in the center of your . It's a hole that lets into the eye. Your pupil is . A cow's pupil is .

The aqueous humor is a fluid that helps the cornea keep its shape

The iris is a that controls how much enters the eye. It is suspended between the and the . A cow's iris is , but a human's iris varies in r.

The lens is a structure that makes an on the eye's . The lens in so that it can change shape, on objects at different distances.

The vitreous humor is a , clear jelly that helps give the eyeball its

The sclera is a , , outer covering of the eyeball

The tapetum is the , shiny material located behind the . Found in animals with good , the tapetum light back through the .

The optic nerve is a bundle of that carry information from the to the .

The blind spot is the place where all nerves from the join to form the . Each eye has a blind spot where there are no cells.

Cones are one kind of cells in the retina. Cones give you in light.

Rods are one kind of cells in the retina. Rods respond to light.