SPECIAL SENSE Structures -- To Know
The following is the list of structures you need to know for the
lab practical. As much as possible,
I have followed the order of presentation in the book.
SPECIAL SENSES
Vision: The Eye
Accessory Structures: Eyebrow, palpebrae (eyelashes, canthi, caruncle,
tarsal plates
tarsal glands), conjunctiva (ocular and palpebral), lacrimal apparatus (gland,
puncta, lacrimal sac, etc.)
Eyeball: poles (anterior, posterior), pupil
Tunics:
1. Fibrous -- Sclera (continuous with epineurium of optic nerve/dura mater
of the brain),
cornea
2. Vascular (Uvea) -- choroid, ciliary body with suspensory ligaments, iris
3. Sensory (Retina) -- pigmented layer, photoreceptors (cones and rods
[bipolar
neurons]), bipolar cells, ganglions cells (axons are optic nerve);
retina with optic disc, macula lutea, fovea centralis
Posterior segment with vitreous humor, anterior segment with aqueous humor
Scleral Venous Sinus (Canal of Schlemm)
Lens
Hearing and Balance: The Ear
Outer Ear: auricle (pinna), external auditory canal (meatus), tympanic
membrane,
Ceruminous glands
Middle Ear: pharyngotympanic (auditory, Eustachian) tube; ossicles: malleus (hammer),
incus (anvil),
stapes (stirrup); stapedius/tensor tympani muscles; round/oval windows
Inner Ear: Bony (osseous) labyrinth, membranous labyrinth;
perilymph, endolymph;
vestibule/semicircular
canals (vestibular apparatus for balance), cochlea (hearing)
Cochlea: Modiolus, cochlear duct (filled with endolymph in scala media), scala
vestibuli/tympani (filled with perilymph and abutting oval/round windows,
respectively); scala media containing spiral organ of Corti,
with vestibular,
tectorial
and basilar membranes, the last which contains "tuned" fibers and
supports hair cells
Vestibule: utricle and saccule, each with a macula (hair cells, otolithic membrane)
Semicircular canals: ampulla, with crista ampullaris and cupula
Vestibulocochlear nerve (cranial nerve number VIII): vestibular and cochlear branches