Richland College
Biol. 2401
Marieb A&P Lab Manual - 11th Edition
ACTIVITY 5: Audiometry
SPECIAL SENSES:
ANATOMY OF THE EYE & VISUAL TESTS & EXPERIMENTS
There are 2 separate exercises—one for anatomy and one for the tests
OBJECTIVES
1. To describe the structure and function of the accessory visual structures.
2. To identify the structural components of the eye.
3. To describe the cellular makeup of the retina.
4. To explain the difference between rods and cones in visual perception and localization.
5. To discuss the importance of the pupillary and convergence reflexes.
6. To define the following terms:
refraction, accommodation, convergence, emmetropia, myopia, hyperopia, astigmatism,
conjunctivitis, cataract, glaucoma
7. To perform some sensory tests, recognizing the stimulus and the normal response.
NOTES:
STRUCTURES OF THE EYE
I. Accessory structures of the eye
 6 extrinsic eye muscles innervated by
CN III, IV and VI:
superior rectus
inferior rectus
medial rectus
lateral rectus
inferior oblique
superior oblique

2 intrinsic eye muscles:
Iris (2 muscles)
ciliary muscle

Lacrimal apparatus:
lacrimal glands, sac and duct
II. Anatomy of the eyeball
3 tunics:
 sclera
 choroid
 retina
anterior vs. posterior cavity
aqueous humor vs. vitreous humor
canal of Schlemm
cornea
pupil
iris
lens
ciliary body
suspensory ligament
III. Retina
 3 layers:
ganglion cell layer
bipolar cell layer
photoreceptor layer (sensory receptor): rods vs. cones
 Regions:
optic disc – no photoreceptors, and responsible for the blind-spot
macula lutea - fovea centralis (greatest density of cones)
ACTIVITY 1-2: IDENTIFYING EYE STRUCTURES
EYE MODELS:
 6 extrinsic eye muscles
 levator palpebrae muscle
 3 nerves innervating the muscles (but NOT which nerve innervates which muscle)
 lacrimal apparatus: lacrimal gland, lacrimal sac, nasolacrimal duct
 3 wall layers: sclera, choroid, retina
 ALL structures labeled on eye in lab book
on diagram only (not on models): macula and fovea centralis
Canal of Schlemm
DISSECTION of cow eye (in lab book):
optic nerve
ciliary body
cornea
vitreous humor
pupil
aqueous humor
iris
optic disc
lens
tapedum lucidum
3 wall layers:
 sclera
 choroid
 retina
ACTIVITY 3: MICROSCOPIC ANATOMY OF THE RETINA
MICROSCOPY: section of the eye
ID sclera, choroid, retina
3 layers of the retina: ganglion cells, bipolar cells, rods/cones layer
ACTIVITY 4: VISUAL PATHWAYS
cross over of fibers along the neural pathways
optic chiasma
optic nerve vs. optic tract
visual fields of each eye
VISUAL TEST PROCEDURES:
ACTIVITY 1: BLIND SPOT
ACTIVITY 2: NEAR-POINT OF ACCOMMODATION
ACTIVITY 3: VISUAL ACUITY (Snellen eye chart)
ACTIVITY 4: ASTIGMATISM
ACTIVITY 5: COLOR BLINDNESS
ACTIVITY 6: DEPTH PERCEPTION
ACTIVITY 7: EYE REFLEXES
 Photopupillary Reflex
 Accommodation Pupillary Reflex
 Convergence Reflex
FOR EACH SENSORY TEST:
What is the stimulus?
What is the normal response?
What is the purpose of response?
OPHTHALMOSCOPIC EXAMINATION
NOTE: Histology Atlas at Martini website. Open MAP, click on STUDY AREA, which takes you to the
Martini website.
Vision.doc