BIOL1410 Lecture Notes – Fall 2024 Unit 20: Special Senses

Flashcards for BIOL1410 Lecture Notes - Fall 2024 Unit 20: Special Senses

Eye

A three-layered sphere filled with fluid, responsible for sight.

Sclera

Avascular connective tissue that is the white part of the eye.

Cornea

Transparent, avascular connective tissue that covers the anterior part of the eye.

Conjunctiva

Vascular mucous membrane covering the anterior sclera.

Choroid

Contains melanin and is highly vascular; located posterior in the eye.

Ciliary Body

Anterior part of the vascular tunic that includes the ciliary muscle and ciliary processes, focusing the lens.

Iris

The colored part of the eye.

Pupil

Hole in the iris.

Retina

The sensory tunic of the eye.

Rods

Photoreceptors responsible for black and white vision.

Cones

Photoreceptors responsible for color vision.

Fovea Centralis

Area of greatest visual acuity, containing no rods, just cones.

Optic Disc

Blind spot where blood vessels and the optic nerve exit the eye.

Lens

Avascular, transparent structure that can develop cataracts.

Cataracts

Clouding of the lens.

Anterior Segment of Eye

Segment anterior to the lens, containing aqueous humor.

Aqueous Humor

Fluid similar to plasma, located in the anterior segment of the eye.

Posterior Segment of Eye

Segment posterior to the lens, containing vitreous humor.

Vitreous Humor

Gel-like substance in the posterior segment of the eye.

External Ear

Conducts sound; consists of the auricle, external auditory canal, and tympanic membrane.

Auricle (Pinna)

Elastic cartilage covered with skin; part of the external ear.

External Auditory Canal

Also called the meatus; part of the external ear.

Tympanic Membrane

Also called the eardrum; part of the external ear.

Middle Ear

Conducts sound; contains the Eustachian tube and ear ossicles.

Eustachian Tube

Also called the pharyngotympanic tube.

Malleus

Secured to the tympanic membrane; one of the ear ossicles.

Incus

One of the ear ossicles.

Stapes

Transmits sound to the inner ear via the oval window; one of the ear ossicles.

Inner Ear (Labyrinth)

Conducts sound; contains the bony and membranous labyrinths.

Bony Labyrinth

Tunnels in the temporal bone that contain perilymph.

Semicircular Canals

Concerned with equilibrium; located in the bony labyrinth.

Vestibule

Concerned with equilibrium; located in the bony labyrinth.

Cochlea

Concerned with hearing; located in the bony labyrinth.

Membranous Labyrinth

Surrounded and protected by the bony labyrinth and contains endolymph.

Semicircular Duct

Located inside the canals.

Utricle and Saccule

Located inside the vestibule.

Cochlear Duct

Located inside the cochlea.

Scala Vestibuli

Upper channel in each coil of the cochlea; contains perilymph.

Scala Tympani

Lower channel in each coil of the cochlea; contains perilymph.

Cochlear Duct

Middle channel in each coil of the cochlea; contains endolymph.

Vestibular Membrane

Membrane between the cochlear duct and scala vestibuli.

Basilar Membrane

Membrane between the cochlear duct and scala tympani.

Tectorial Membrane

Covers hair cells in the inner ear.

Hair Cells

Receptor cells in the inner ear that synapse with neurons and send impulses to the brain.