Dissection of a Cow's Eye

Introduction: In this laboratory, we set out to dissect a cow's eye and identify the different parts of eyes and their function. We were given the procedure to open the eye, as well as a sheet that told us what the components of the eye looked like.

Procedure: We started off by removing all of the excess fat and muscle tissue surrounding the eye with a scalpel. After it was removed, we cut into the top of the cornea. After the liquid inside, the aqueous humor, we proceeded to cut through the sclera, down through the middle of the eye. This allowed to to cut the eye in half. Next, we took the half of the eye with the cornea and cut it. This allowed us to pull out the iris. We then took out the vitreous humor, which was in the back of the eye. With this done, we removed the lens from the back of the eye as well. With everything removed, we observed the retina and the optic nerves, also in the back of th eye.

Results: After dissecting the eyeball, we identified each part and it's function. The sclera is the outside of the eyeball, the shell that is attached to the fat and muscle surrounding the eye. The first part of the functioning eye was the cornea. The cornea is a tough outer shell around the iris that protects the eye. It also bends light that enters the eye, which results in the image we see. Inside the cornea is the aqueous humor. This is a clear jelly-like substance that simply keeps the cornea's shape. Next was the iris. The iris is the colored part of the eye, and it's function is to control the amount of light that enters into the eye. Inside of the iris is the cow's pupil. The pupil is the dark spot in the middle of the eye. The purpose of the pupil is also to let light into the eye, though it is more concentrated. Inside of the eye is the vitreous humor, another clear substance that helps give the round shape to the eyeball. Next is perhaps the most interesting part of the eye, the lens. The lens is a clear structure in the eye that takes light from a stimulus and reflects it on to the retina to create an image. The lens is able to change it's shape, so that the eye can focus better on things at different distances. The retina is at the back of the eye, behind the iris and lens. Once the light has been reflected onto the retina, it sends a message to the brain via optic nerves. The brain then processes the data and sends what the image should be back to the retina, which is how we see.

Conclusion: