Anatomy Chapter 8

The cochlea is a membranous labyrinth containing structures essential for the propagation of sound waves to the cochlear nerve, which transmits the stimulus to the auditory cortex for neural interpretation. What is the function of the basilar membrane, hair cells, and tectorial membrane?

1. The structure that bends the hearing receptors but does not vibrate itself is tectorial membrane. 2. Hearing receptors are embedded in the tectorial membrane. 3. As a result of this vibration, hair cells is/are bent. 4. Hearing receptors are called hair cells. 5. Sound waves cause the basilar membrane to vibrate first. 6. Hearing receptors are connected to the basilar membrane by supporting cells.

The tip of the tongue is very sensitive to which taste sensation(s)?

Both sweet AND salty are correct.

Focusing the light rays involves which of the following?

Change in the shape of the lens

The olfactory cells are _______.

ciliated neuroepithelial cells

A delicate membrane that lines the eyelids and covers part of the outer surface of the eyeball is called the _______.

conjunctiva

The transparent anterior portion of the fibrous layer of the eye is the _______.

cornea

Which of the following structures refract light before it hits the retina?

cornea, humors, and lens

The optic disc marks the _______.

exit of the optic nerve, N II

What condition results from an abnormally high pressure inside the eye?

glaucoma

What is a possible cause of conduction deafness?

inability of auditory ossicles to vibrate

Which of these structures is part of the system that produces and drains tears?

lacrimal gland

Which of these provides sensory input that helps keep the head erect?

maculae of the vestibule

Which of the following is the auditory ossicle that attaches to the tympanic membrane?

malleus (hammer)

The roles of the parts of the ear

middle and outer ear: hearing inner ear- both hearing and equilibrium

The term for nearsightedness is _______ and the term for farsightedness is _______.

myopia; hyperopia

Within the membranous labyrinth of the cochlea is the primary organ of hearing. It is called the _______ and contains the hair cells associated with hearing.

organ of Corti

What is the function of the otoliths?

responding to changes in the pull of gravity and in acceleration when the body moves

The photoreceptors in the eye are found in the _______.

retina

Which of these is part of the sensory layer of the eye?

retina

The outer white layer of the eyeball that is also called the fibrous tunic is the _______.

sclera

What part of the inner ear contains receptors for dynamic equilibrium?

semicircular canals

Which of these are oriented in the three planes of space, allowing sensation of movement in any plane?

semicircular canals

When there is degeneration or damage to the receptor cells in the organ of Corti, to the cochlear nerve, or to neurons of the auditory cortex, the condition is called _______.

sensorineural deafness

The conduction of a sound vibration from the middle ear to the inner ear is created by the vibration of the _______.

stapes in the oval window

The maculae of the vestibule record _______ whereas the crista of the semicircular canals record _______.

static equilibrium; dynamic equilibrium

The receptors for _______ and _______ are classified as chemoreceptors.

taste; smell

Where are olfactory receptors located?

the superior region of the nasal cavity

What sensation allows someone to enjoy the "beef taste" of a steak?

umami

The division of cranial nerve VIII carrying information from the maculae and crista is the _______ branch.

vestibular

When a bright light shines in the eye, what reflex response takes place?

Photopupillary reflex

Sound waves that reach the hearing receptors must be transmitted through the eardrum, ossicles, and oval window before fluids surrounding the hearing receptors begin to vibrate. Rank the following in order beginning with the first mechanical structure that helps transmit sound waves to the inner ear.

Tympanic membrane Malleus Incus Stapes Oval window Cochlea Organ of Corti

What term refers to the ability to focus on close objects?

accommodation

The sensory hair cells of the organ of Corti are located on the _______.

basilar membrane

Electrical signals pass from the photoreceptors via a two-neuron chain: They pass from _______ cells to _______ cells before leaving the retina via the optic nerve.

bipolar; ganglion

Both types of equilibrium involve hair cells and a gelatinous substance that, under certain circumstances, causes the hair cells to bend. However, the mechanisms of action to maintain static and dynamic equilibrium involve different structures. Which structures are used in each type of equilibrium? The sense of equilibrium responds to movements of the head. In the case of static equilibrium, information is gathered regarding head position when the body is not moving, such as when you are nodding your head. Dynamic equilibrium monitors angular or rotational movements of the head when the body is moving, such as a figure skater's spinning, but maintaining balance. Drag and drop the correct term to the appropriate sentence.

Dynamic equilibrium receptors are located in the semicircular canals Static equilibrium is detected by maculae Dynamic equilibrium is detected by the crista ampullaris The bending of static equilibrium receptors is caused by otoliths. Static equilibrium receptors are located in the vestibule The bending of dynamic equilibrium receptors is caused by the cupula.

What part of the retina contains only cones and is the area of greatest visual acuity?

Fovea centralis

Why is it harder to determine where a sound originates when one auditory canal is completely blocked with earwax?

Since one ear is functionally deaf, the brain can't compare input from both cochleae to localize a given sound.

The sense of equilibrium responds to movements of the head. It is divided into two types--static and dynamic equilibrium. Describe and give an example of these two types of equilibrium. Select all the statements that accurately describe equilibrium.

Static equilibrium monitors head position when the body is not moving. Dynamic equilibrium monitors angular or rotational movements of the head when the body is moving. An example of static equilibrium occurs when nodding one's head "yes." An example of dynamic equilibrium occurs when a figure skater spins.

How do organs of equilibrium help us maintain our balance?

The macula sends information on head position and the crista ampullaris sends information on rotation movements to the cerebellum for integration.