Eye or Orbit

Question 1

What bones make up the Orbit

Answer 1

The Frontal, zygomatic, maxilla, sphenoid, lacrimal, ethmoid and palantine

Question 2

Function of the sclera

Answer 2

Will provide protection from external and internal forces, provides attachment for EO muscles

Question 3

Why is the cornea transparent

Answer 3

in the stroma the collagen is laid in sheets of parallel fibres and the sheets are laid on top of each other at angles. there are 200-300 layers,

Question 4

5 layers of the cornea

Answer 4

Epithelium, Bowman’s Capsule, Stroma, Desemet’s Membrane and endothelium

Question 5

What is the function of the anterior angle

Answer 5

At the junction where the iris muscles meet the ccornea. Is the location where the aquous humour drains. Will then drain throgh the trabeculae and then into the canal of schlemm

Question 6

What is the middle layer of the eye called? And what are its three layers?

Answer 6

Uvea comprising the Cilliary bodies, Choroid and the iris

Question 7

Function of the cilliary bodies

Answer 7

To shape the lens to accomodate the lens and produce the aqueous humour

Question 8

Aqueous Humour is produced by?

Answer 8

The Cilliary Bodies

Question 9

What two muscles make up the iris and what is their innervation

Answer 9

The Dilator pupillae by the SNS and the pupillae sphintor by the PNS of the Edinger Westfall nucleus

Question 10

What is the choroid

Answer 10

Is a layer that provides nutrients to the retina from above

Question 11

What is the third layer of the eye

Answer 11

Retina

Question 12

What is special about the fovea

Answer 12

Is a depressed pit that controls central vision and colour vision by only having cones and no rods

Question 13

What are the Lamina Cribosa

Answer 13

A mesh of dura in which the optic nerve passes through

Question 14

Describe the eyelids

Answer 14

○ A transition between conjuctiva and skin
○ Two muscles which are antagonistic
§ Orbicularis Oculi (CNVII)
§ Levator palpebare superiosis (CNIII)

Question 15

Retinal Blood Supply

Answer 15

Off the opthalmic artery is the Central retinal artery which suplies the retina from below, however there are also long and short cilliary arteries which run in the choroid and supply the retina from above. There is also an anterior cilliary artery which winds round the eye and supplies anterior structures such as the cilliary bodies, the iris, conjunctiva, sclera and the rectus muscles

Question 16

Difference between the the aqueous humor and the vitrous humor

Answer 16

Aquaous is between the cornea and the iris while vitrous is between the retina and the lens