Eye Dissection

1
Eye Dissection

• January 23, 2003
• Heather Mueller

2
Eye Anatomy

3
Dissection Materials

• What will you need?
• Eye Specimen
• Gloves (Latex Allergies)
• Scissors
• Probe
• Scalpel
• Waste Container
• Hand Lens
• Soap Water

4
Exterior of Eye

• Fat
• Protects the eye.
• Cushions from bone.
• Appears White
• Muscles
• Rotate eye (6 in Humans)
• Appear Red-Brown
• Sclera
• Tough external white protective outer covering

5
Initial Incisions

• Cornea
• Clear portion of the sclera in the front of the
  eye
• Removal
• Make shallow cuts around the cornea where it
  meets the sclera
• NOTE
• The liquid aqueous humor is behind the cornea.
  Liquid may squirt out!

6
Iris Pupil

• Iris Colored portion of the eye. The iris has
  circular muscles on the outside and radial
  muscles on the inside in order to dilate or
  constrict the pupil of the eye.
• Pupil Dark or black part of the eye. There
  is no structure here. The pupil determines the
  amount of light allowed to hit the retina.
  Contracts in bright light. Dilates in dark
  light.

7
Iris Removal

• Make shallow cuts around the iris at the point in
  which it meets the sclera.
• NOTE The lens is found under the iris. Refrain
  from damaging the lens.
• NOTE Humor is also found under the lens. BE
  CAREFUL liquid again may squirt out.

8
Lens

• The lens appears as a small marble shaped
  structure. Remove the lens.
• The lens focuses light onto the retina. Muscles
  can change the lens shape.

9
Retina and Tapetum

• Sensory and Reflective Layers
• Retina Milky white in color. Receives sensory
  information and sends info the brain. Rods sense
  dark and light. Cones sense color.
• Tapetum Mother of Pearl Blue. Found only in
  animals. The structure that makes eyes glow
  highly reflective. Maximizes night vision.

10
Choroid and Optic Nerve

• The choroid is under the Tapetum. The choroid is
  rich in blood vessels. The blood vessels supply
  the retina with blood.
• The Optic Nerve is seen as a small depression in
  the tapetum. The optic nerve sends messages
  received in the retina to the brain for
  processing.

11
Additional Resources

• Mindquest.net/biology/videos/coweye.html
• www.exploratorium.edu/learning_studio/cow_eye/inde
  x.html