Eye

Question 1

Eye functions

Answer 1

• outgrowth of nervous system in combination with ectoderm
• sight/vision: color/BW, day/night
• locomotion
• nutrition
• defense
• seasonality/reproduction

Question 2

What is the only place in the body where you can see the CNS?

Answer 2

The back of the eye

Question 3

Tunics

Answer 3

Fibrous: corneosclera
- sclera: opaque white
- cornea: clear
Vascular: uvea
Nervous: retina (direct extension of CNS)

Question 4

Chambers

Answer 4

Anterior chamber
- cornea to iris
- aqueous humor
Posterior chamber
- iris to lens
- aqueous humor
Vitreous chamber
- behind lens
- vitreous humor
- makes up 2/3 of globe

Question 5

Fibrous tunic

Answer 5

Cornea
- corneal epithelium: non keratinized, stratified squamous
- Bowman’s membrane: basement membrane of corneal epithelium
- stroma: dense fibrous CT
- Descemet’s membrane: basement membrane of endothelial layer
- corneal endothelium
Sclera
- dense fibrous CT

Question 6

Iris (uvea)

Answer 6

• forms border between anterior and posterior chambers
• pigmented epithelium
• smooth muscle: contractile, autonomic control

Question 7

Ciliary body (uvea)

Answer 7

• between iris/choroid
• zonular fibers
• blood-aqueous barrier
• secrete aqueous humor

Question 8

Zonular fibers are attached to the _____

Answer 8

Lens, NOT the iris!

Question 9

Choroid

Answer 9

• rear portion

- between retina and sclera

Question 10

Lens

Answer 10

• transparent
• avascular
• capsule
• subcapsular epithelium
• fibers (collagen/water)

Question 11

In the lens, the basement membrane is on the _____

Answer 11

Outside

Question 12

Retina

Answer 12

• innermost layer
• 5-7 layers
• contains vitreous fluid
• optic disc
• tapetum: reflective portion (species variation)