Cow Eye Dissection!!!

Today we dissected a cow's eye...and it was a very intense process. We took the cow's eye straight from the jar and set it on a paper towel. Using an Exacto knife and using the online intructions from http://www.exploratorium.edu/learning_studio/cow_eye/doit.html we began cutting away the fat and muscle surrounding the eye. Our eye had quite a bit of fat and so our designated surgeon, Betsy, began chopping away. It took us a while to get rid of the excess junk around the eye, but eventually we had the eye dissected down to its sclera (the white, tough, outer edge) and the cornea. Our next step was to make an incision in the cornea until clear liquid (called the aqueous humor) was released. We then made an incision through the middle of the sclera so that we could have a good look into the middle of the eye. I helped at this point and Betsy and I removed some gooey clear liquid from the eye (called vitreous humor) . From there we pulled out the iris which was a round, thin black piece that ripped a little as we removed it from the sides of the cornea wall. We then located the lens (which looked like a clear marble) and removed it from the eye. Our lens was a little cloudy which meant that our cow most likely had cataracts.

I really enjoyed this project despite the fact that I was nervous to participate in the dissection when we first began. The slimy nature of the eye and the fact that I could still picture it being connected to the animal was a bit overwhelming at first, but after cutting into the object and using the parts we found inside as tools to help us understand how the eye functions, I began to appreciate our assignment. From this lesson I also learned about the similarities and differences between human and cow eyes. I think this type of project would be perfect for kids in upper elementary grades or jr. high because they can properly handle the instruments required and they will be able to appreciate the information learned from such a dissection.