Chapter 14: Eyes

Question 1

Eye is protected by….

Answer 1

A bony orbital cavity surrounded by a cushion of fat.

Eye lids: provide shade and create an airtight se when eyes are closed

Eye lashes keep dust out of eye

Question 2

Tarsal plates

Answer 2

Strips of connective tissue that give upper lids shape.
- contain meibomian glands which are modified sebaceous glands that secrete oily lubricant that stops years from overflowing. Air tight.

Question 3

Thin mucous membrane later that folds like an envelope between the eyelids and covering the anterior eyeball up to the edge of the cornea.

Answer 3

Conjunctiva.

Question 4

Two types of Conjunctiva:

Answer 4

Palpebral- lines lids and is vascular

Bulbar- covers sclera

Question 5

Lacrimal Apparatus

Answer 5

Provides constant irrigation to keep conjunctiva and cornea moist
- lacrimal gland secretes tears

Question 6

6 muscles that attach eye to its orbit and direct eye movements
- straight and rotary movements

• each muscle moves the same (yoked) way in the other eye: one looks right the other looks right (conjugate movement)

Answer 6

Extraocular muscles

• four straight (recurs)
  - superior, inferior, medial, lateral
• two oblique
  - superior and inferior

Question 7

Cranial Nerves for Eyes and Eye Movement

Answer 7

6: abducens nerve (lateral recurs muscle which abducts eye)
4: trochlear (inner area superior oblique muscle)
3: oculomotor (superior, inferior, medial, and recurs obliques)

Question 8

Afferent: carries message to the brain

Efferent: carries messages to structure

Answer 8

Motor movements

Question 9

Three Coats of Eye:

Answer 9

Sclera: outer layer.
- tough protective white covering. Connects with cornea over iris and pupil.

Choroid: middle later
- dark pigmentation that prevents light from coming in. Heavily vascularized to deliver blood to retina. Contains pupil and iris and lens and chambers.

Retina: inner layer.
- visual receptive layer that changes light waves into nerve impulses. Contains optic discs and retinal vessels.

Question 10

Open space between eye lids

Answer 10

Palpebral fissure

Question 11

Cornea

Answer 11

Thin and transparent layer over anterior chamber and iris and pupils

• corneal reflex. Trigeminal nerve five

Question 12

Pupil construction

Answer 12

Nerve 3

Question 13

Anterior and posterior chambers

Answer 13

Contain clear watery aqueous humor that delivers nutrients to the surrounding tissues

Question 14

Retina

Answer 14

Visual receptive layer of the eye in which light waves are changed into nerve impulses

Question 15

Area in which fibers from the retina converge to form the optic nerve

Answer 15

Optic disc

Question 16

Pupillary Light Reflex

Answer 16

CN 3 for efferent

CN 2 for afferent

Question 17

Fixation

Answer 17

Direction of the eye towards an object