Anatomy // Chapter 8 Special Senses

What structure is lined with ceruminous glands?

External Acoustic Meatus (Auditory Canal)

*(T/F)* The internal (inner) ear functions in the sensation of hearing only.

False

What part of the eye has the greatest visual acuity?

Fovea Centralis

Hearing receptors within the spiral organ of Corti are called ________.

Hair Cells

What gland releases tears onto the anterior surface of the eyeball?

Lacrimal

What flexible, crystal-like structure of the eye focuses light on the retina?

Lens

The vibration of sound waves causes the tympanic membrane, or eardrum, to move against an ossicle known as ________.

Malleus (Hammer)

Identify the pathway of vibrations as they travel from one ossicle to the next.

Malleus, Incus, Stapes

The inability to see distant objects is termed "nearsighted" or ________.

Myopia

Fibers from the medial side of each eye cross over to the opposite side of the brain at the ________.

Optic Chiasma

What region of the retina lacks photoreceptor cells?

Optic Disc (Blind Spot)

What is the pathway along which images received by the retina of the eye will travel into the brain?

Optic nerve, Optic chiasma, Optic tracts, Thalamus, Optic radiation, Occipital lobe

Tiny stones made of calcium salts that roll in response to changes in gravitational pull are called ________.

Otoliths

When Ms. Miller flipped the lights on and off in her dark classroom, her students experienced ________.

Photopupillary Reflex

The function of the choroid layer of the eye is to ________.

Prevent light from scattering inside the eye

Layer that contains millions of photoreceptors

Retina

Which layer of the eye contains rods and cones?

Retina

White of the eye

Sclera

The fibrous covering of the eye consists of the white outer layer, known as the ________, and a transparent portion known as the ________.

Sclera, Cornea

The aqueous humor of the eye is reabsorbed into venous blood through the ________.

Scleral Venous Sinus (canal of Schlemm)

Dynamic equilibrium receptors that detect information about angular or rotational movements of the head are housed in the ________.

Semicircular Canals

What hearing disorder arises when there is damage or degeneration of receptor cells in the spiral organ of Corti, cochlear nerve, or neurons in the auditory cortex of the brain?

Sensorineural Deafness

Hair cells that function as hearing receptors are located within the ________.

Spiral Organ of Corti

What sensation is related to sitting motionless at a desk studying your anatomy and physiology material?

Static Equilibruim

What is the function of the tarsal glands?

Tarsal glands produce an oily secretion that lubricates the eye.

*(T/F)* Conduction deafness may result from earwax buildup or the fusion of the ossicles.

True

*(T/F)* In order to hear sound, vibrations pass from the eardrum to the ossicles, and on to the oval window.

True

*(T/F)* The "stirrup" is also referred to as the stapes.

True

*(T/F)* The bony labyrinth of the internal ear consists of the cochlea, vestibule, and the semicircular canals.

True

*(T/F)* The normal resting eye is generally "set" for distant vision.

True

*(T/F)* The pupil is the circular opening in the iris through which light passes.

True

Jake was struck in the head during a baseball game. Which of the following could impair the sense of hearing if damaged?

Tympanic Membrane

What membrane divides the outer ear from the middle ear?

Tympanic Membrane (Ear Drum)

Static equilibrium receptors are located in the ________.

Vestibule

Which cranial nerve transmits both hearing and equilibrium information to the brain?

Vestibulocochlear Nerve (VIII)

The gel-like substance that reinforces the eyeball and prevents it from collapsing inward is the ________.

Vitreous Humor (body)

What is a sex-linked condition that more often affects males?

Color Blindness

A person with total color blindness may lack ________.

Cones

Explain how the function of rods and cones differ.

Cones help you see color, while rods help you see dark/dim lights and greys.

The membrane that covers the outer surface of the eye and lines the eyelids is the ________.

Conjunctiva

The transparent portion of the fibrous layer of the eye is the ________.

Cornea

What is the correct order of the parts through which light passes as it enters the eye?

Cornea, Aqueous humor, Lens, Vitreous humor

What is the ability of the eye to focus on close objects?

Accommodation

What vision disorder results from the loss of lens transparency?

Cataracts