Sheep Eye Dissection Lab

From the anterior view of the sheep eye, the eyelid, cornea, sclera, and fatty tissue are visible. The posterior view of the eye presents the optic nerve, the extrinsic muscle, and more fatty tissue, which covers the entire outer area of the eye. In the internal posterior view, the vitreous humor, retina, and choroid can be observed. The internal anterior view shows the ciliary body, lens, pupil, and iris.

The sclera is the tough and thick white outer cover of the eyeball. It is covered with a layer of fatty tissue and muscle tissue. The choroid brings blood, oxygen, and nourishment to the eye. The cornea, which is the cloudy and tough cover over the iris and is located just behind the the pupil's opening, helps to protect the eye and focus light. The cornea is cloudy due to the cataract condition, which prevents or reduces the amount of light that reaches the cornea. The iris, which is the brown colored part of the eye controls the amount of light that penetrates the eye. The lens, which is the clear structure that adjust the eye's focus and is responsible for about 20% of the eye's focusing, was surrounded by the ciliary body. The ciliary body encircles the lens and controls its shape with muscles.





The optic nerve is a bundle of nerve fibers that carry information from the retina to the brain for processing. The pupil is the oval shaped hole that allows light to enter the eye. In humans, the pupil is circular. The retina is the layer of light sensitive cells that line the inner eyeball. The retina contains rods, which are photoreceptor cells that respond to dim light. The vitreous humor is the clear gel that fills the space between the lens and the retina of the eyeball.




The tapetum lucidum, which reflets light back into the retina, is the iridescent blue, shiny, and reflective material located directly behind the retina and is part of the choroid layer in nocturnal animals. Although humans lack the tapetum, animals use this to see in the dark, which is why animal eyes glow occasionally glow in pictures with flash.