Cow Eye Dissection
Suggested Time
Time45 min
Span1 Class Period
Ideal Group Size
2 students per group
Safety Supplies (Required)
Safety Supplies (Recommended)
ViewRecommended Specimen(s)
Recommended Dissecton Supplies
General Dissection Resources
Cow Eye Dissection Videos
Cow Eye External Anatomy
- Obtain a preserved cow eye, and then place it on your dissecting tray.
- Examine the external characteristics of the eye. Use the image below and identify:
- Cornea—at front of the eye; allows light to enter the eye
- Optic nerve—at back of the eye; transmits nerve impulses to the brain
- Fat
- Muscle
- Trim the fat and muscle from around the eye using your scissors. Be careful not to cut the optic nerve on the back of the eye. Tip: Use your fingers to pull the fat and muscle away from the eye, then cut it away.
- Identify the sclera, or tough outer covering of the eyeball.
Cow Eye Internal Anatomy
- Hold the eye between your thumb and forefinger, as shown below. Using scissors or a scalpel, carefully cut the eye in half, separating the front and back of the eye.
- Examine the inside front portion of the eye.
- Remove the gelatinous vitreous humor and hard lens. Preservatives make the lens hard and opaque, but in living organisms the lens is clear and flexible.
- With scissors, cut around the edge of the cornea to expose the iris and pupil.
- Use forceps to detach the iris from the sclera and examine the structures.
- Examine the back portion of the eye.
- Carefully remove the retina. Notice it connects to the back of the eye at the junction of the optic nerve; this is the blind spot.
- Examine the iridescent, reflective layer beneath the retina. This layer is called the tapetum lucidum. Cows and other nocturnal animals have a tapetum lucidum, but humans do not.
- Follow all clean-up and disposal instructions.
