Biology Dissection

J+M+J

I’m doing biology this year, and so have been going to a dissection class with Landon and a bunch of other homeschoolers. There are three classes, and the first time we did the classic frog. This week, the second class, we did a cow’s eye and a sheep brain. (I made the pictures really small so you only have to see them if you want to. Click them to see full size.)

The cow’s eye was a little intimidating at first, looking at me right there on the plate, but once we got into it, it was really interesting. We took off the cornea first (protects the eye), and then the iris, (gives the eye it’s color and controls the amount of light entering) and then the lens (focuses light). The cornea was a thin and clear layer covering the entire eye and I was thinking of it as I took out my contacts at night.  Next we found the optic nerve, which carries messages from eye to brain.

The white circle in the center of this picture is the optic nerve, which sends images to the brain. It is cushioned by many layers of fat and muscles for protection because if you damage it you can’t see.

The retina, where the colors and details of the picture is detected, was especially interesting. It was shiny and looked like the inside of a mother of pearl shell, which I never expected.

The sheep brain wasn’t quite as interesting as the eye because pretty much the only thing to see is the cerebrum (the front half that controls most voluntary movement) and the cerebellum (the back half that holds memory and small motor skills).

A+M+D+G