John Here:

Well it’s been a little while but we’re back! Holidays seem to get out of control and getting swamped with things to do always happens not to mention it’s cold and flu season :(.   With all that behind us now, what better way to start the new year than with a good old “Cow Eye Dissection”.  Actually I’m sure there are much better ways to start the new year but we just finished our Nervous System Unit and now we are covering some special senses.  This is a good, quick, one day lab that is great for learning the structures of the eye up close and personal. (Please note you need to have gone over eye anatomy and preview the lab ahead of time to make sure you can get finished in one class period.)   Beware this can be considered a little gross for some people but in anatomy this is pretty cool.

 

 

Vision is the most important sense by which humans gain knowledge of the external environment. Whenever someone says they are a visual learner I say to myself “Duh!, everybody is!” I mean what else would you use, your nose?

The first order of business is to remove the muscles that move our eyes and the fat that cushions and protects them.

This is what you generally end up with, one regulation cow eyeball.

 

After some identification, the cornea is removed to reveal the structures inside the eye.

 

As the students answer some questions and make some diagrams, the lens is removed for examination. Here it looks like a round, orange marble.

 

Finally the eye is turned inside out to reveal the retina. A common myth is that bulls get angry when they see red. The problem with that is that cattle are red-green color blind so they can’t tell if something is red. They can see some colors but red is not one of them.

Students really like this lab and it leads into the next lab which is the Visual Tests and Experiments Lab where eye physiology and  function is demonstrated.

Thanks for looking and Happy New Year!

John

The Teacher Team