What’s in an Eye? The Eye’s Components and the Diseases that Affect Them

What’s in an Eye? The Eye’s Components and the Diseases that Affect Them


Ishara Mills-Henry
Program Director
Science of the Eye: Bringing Vision into the Classroom
Department of Biology
Cambridge, MA

Lesson Feedback


The major purpose of this lesson is to promote the learning of eye function by associating eye problems and diseases to parts of the eye that are affected. Included in this module are discussions and activities that teach about eye components and their functions. The main activity is dissecting a cow eye, which in many high schools is part of the anatomy curriculum. This lesson extends the curriculum by discussing eye diseases that students might be familiar with. An added fun part of the lesson is discussion of what various animals see. The most difficult item to obtain for this lesson is the cow eye. Cow eyes from companies cost between $2 – 4 per eye. Some slaughterhouses/butchers will give you cow eyes for free, or charge a minimal fee. If you use cow eyes from these sources, you should store the eyes in a refrigerated area. Other supplies include: scalpel or razor blade, scissors (optional), dissecting pan or cutting board and wax paper, trash bags. This lesson will not fit into a 50-minute period if students are dissecting. If there is no dissection, 50 minutes should be enough time.

Instructor Biography

When she made this video lesson, Ishara Mills-Henry was Director of MIT’s Program, Science of the Eye: Bringing Vision into the Classroom. Currently, she is an Assistant Professor-Dual Appointment Biology and Chemistry & Food Science at Framingham State University in Framingham, Massachusetts. 

Additional Online Resources

This page, sponsored by the Exploratorium: The Museum of Science, Art and Perception, shows people how an eye works through the dissection of a cow’s eye.

This site, Neuroscience for Kids, has been created for all students and teachers who would like to learn about the nervous system.

This is the site of the National Eye Institute of the Institute of Health

This website – the Anatomy, Physiology and Pathology of the Human Eye – provides a comprehensive overview of subjects discussed in this video lesson.

This site provides an applet that is a simplified model of the eye in which the front of the eye is a single converging lens.

This page, sponsored by Live Science, presents an overview of the human eye and some interesting facts about the eye.

This short TED video provides a fascinating explanation of how the human eye evolved.