EXERCISE 9: Special Senses

DO NOT EXPLOIT.

Gustation

Special sense associated with the tongue.

Papillae

Raised bumps that contain contain the structures (taste buds) for gustatory transduction.

Salty taste

It is simply the perception of sodium ions (Na+) in the saliva.

Sour taste

The perception of H+ concentration.

Alkaloids

Nitrogen containing molecules that are commonly found in bitter-tasting plant products, such as
coffee, hops (in beer), tannins (in wine), tea, and aspirin.

Olfaction

The sense of smell that is also responsive to chemical stimuli.

Olfactory receptor neurons

Are located in a small region within the superior nasal cavity; this regions is referred to as the olfactory epithelium that contains bipolar sensory neurons.

Audition

It is the transduction of sound waves into a neural signal that is made possible by the structures of the ear.

Auricle

The large, fleshy structure on the lateral aspect of the head of the ear.

Tympanic membrane

Also known as the ear drum, which vibrates after it is struck by sound waves.

Malleus

An ossicle that is attached to the tympanic membrane and articulates with the incus.

Incus

It articulates with the stapes.

Stapes

It is attached to the inner ear, where the sound waves will be transduced into a neural signal.

Bony labyrinth

It is composed of a series of canals embedded within the temporal bone.

Cochlea and vestibule

Regions that are responsible for hearing and balance.

Scala vestibuli

It extends rom the oval window, travelling above the cochlear duct, which is the central cavity of the cochlea that contains the sound-transducing neurons.

Scala tympani

The fluid-filled tube within the cochlea.

Vision

The special sense of sight that is based on the transduction of light stimuli received through the eyes.

Eyelids

Contains lashes at their leading edges, help to protect the eye from abrasions by blocking particles that may land on the surface of the eye.

Palpebral conjunctiva

A thin membrane from the inner surface of each lid that extends over the white areas of the eye (the sclera), connecting the eyelids to the eyeball.

Lacrimal gland

The gland that mainly produce tears that is located beneath the lateral edges of the nose.

Fibrous tunic

Outermost layer of the eye, which includes the white sclera and clear cornea.

Sclera

It accounts for five-sixths of the surface of the eye, most of which is not visible, though humans are unique compared with many other species in having so much of the “white of the eye” visible.

Cornea

It covers the anterior tip of the eye and allows light to enter the eye.

Vascular tunic

The middle layer of the eye, which is mostly composed of the choroid, ciliary body, and iris.

Choroid

A layer of highly vascularized connective tissue that provides a blood supply to the eyeball.

Iris

A smooth muscle that opens or closes the pupil, which is the hole at the center of the eye that allows light to enter.

Neural tunic (Retina)

Innermost layer of the eye, which contains the nervous tissue responsible for photoreception.

Anterior cavity

The cavity of the eye that is space between the cornea and lens, including the iris and ciliary body; It is filled with a watery fluid called the aqueous humor.

Posterior cavity

The cavity of the eye that is space behind the lens that extends to the posterior side of the interior eyeball, where the retina is located; it is filled with a more viscous fluid called the
vitreous humor.