Chapter 9 Senses: Seeing and Hearing

_____________ potentials begin with a stimulus, can be weak or strong, and can add together.

Receptor

Place the steps of age-related hearing decline in order of which happens first starting at the top.

1. Loss of ability to hear high frequency tones. 2. Loss of ability to hear low frequency tones. 3. Loss of ability to understand speech.

Which of these fluids is found within the membranous labyrinth of the inner ear?

Endolymph

True or false: In presbycusis, the ability to hear low frequency tones is lost before the ability to hear high frequency sounds.

False

True or false: The loudness of sound is dependent upon the portion of the basilar membrane activated by a specific sound frequency.

False

Select all of the visual disorders that are associated with aging.

Glaucoma Macular degeneration Presbyopia Cataracts

Pigmentation determines the color of the _____________ and in turn the color of your eyes.

iris

Vision is less sharp in dim light than in bright light because:

many rods converge on a single ganglion

The inner layer of the eye that contains photoreceptors is the:

retina

The inner layer of the eye, which contains the visual receptor cells, is called the _____________.

retina

The only layer of the eye that can detect light is the:

retina

Which of the following structures is located within the posterior compartment?

retina vitreous body

Almost half of all diabetic patients will exhibit some form of _____________.

retinopathy

The light-absorbing pigment molecule found in the rods is:

rhodopsin

The _____________ organ (organ of Corti) contains little hair cells within the tectorial membrane.

spiral

The structure that contains the hearing receptors in the cochlea is called the:

spiral organ

Identify the three major parts of the inner ear:

vestibule cochlea semicircular canals

The aqueous humor is located in the _____________ cavity of the eye, which includes both the anterior and posterior chambers.

anterior

The _____________ joins the middle ear to the nasopharynx and helps to equalize air pressure.

auditory tube

When distant objects are viewed, the lens

becomes flat

Receptors that respond to the presence of chemicals in the nearby area are _____________.

chemoreceptors

The vascular middle layer of the eye is called the:

choroid

The part of the inner ear that functions in hearing is the _____________.

cochlea

Absence of the color pigments in the cones results in:

color blindness

List the vents of hearing physiology in the correct sequence:

1. Sound waves enter auditory canal inducing vibration of the tympanic membrane 2. Vibrations move through the ear ossicles and are transferred to the oval window 3. Oscillating movements of the perilymph cause the vibration of the basilar membrane and spiral organ 4. Nerve impulses are formed by the hair cells 5. Nerve impulses travel along the vestibulocochlear (VIII) nerve to the temporal love of the cerebrum

List in order the structures of the ear as they come into play with hearing:

1. auditory canal 2. tympanic membrane 3. stapes 4. cochlea 5. cochlear nerve

_____________ pitched sounds activate the longer fibers near the tip of the basilar membrane, while _____________ pitched sounds activate the shorter fibers near the base of the membrane.

Low; high

The vestibular and tympanic ducts are filled with _____________, while the cochlear duct is filled with _____________.

perilymph; endolymph

The condition in which the lens of an older individual does not accommodate well is known as:

presbyopia

_____________ are stimulated by changes in the concentration of certain chemicals and light rays are detected by _____________.

Chemoreceptors; photoreceptors

Which of these fluids is found within the membranous labyrinth of inner ear?

Endolymph

What are the functions of the ear?

Equilibrium Hearing

True or false: A single receptor potential is able to generate an all-or-nothing response to a stimuli.

False

True or false: Rods are more highly concentrated in the fovea centralis.

False

True or false: The area of the retina that produces the sharpest vision is the optic disc.

False

Match the following disorders of the eye with the correct description:

Hyperopia ---> Farsightedness Myopia ---> Nearsightedness Astigmatism ---> Unequal focusing of light rays on the retina

What is the name of the receptors that are stimulated by tissue damage?

Pain receptors

The bony (osseous) labyrinth is located in which cranial bone?

Temporal

What is the name of the type of receptor sensitive to temperature changes?

Thermoreceptor

_____________ are sensory receptors stimulated by changes in temperature.

Thermoreceptors

True of false: When viewing a boat in the distance from the shore and then looking back at your book, your eyes are able to adjust and focus due to visual accommodation.

True

True or false: The images detected at the retina are upside down and reversed from left to right.

True

The window of the eye is the transparent _____________ which is located anterior to the aqueous humor and the lens helps to focus entering light rays.

cornea

The _____________ divides the eye into an anterior and posterior compartment.

lens

The transparent, elastic structure of the eye which changes shape in response to contraction by ciliary muscles is the _____________.

lens

The type of receptor that senses changes in pressure or movement is a _____________.

mechanoreceptor

Which of the following is the type of receptor that senses mechanical forces by detecting displacement of the tissue in which they are located:

mechanoreceptor

The _____________ labyrinth is a tube of tissue that lines the _____________ labyrinth.

membranous; osseous or bony

The _____________ ear is an air-filled space that houses the three auditory ossicles.

middle

The _____________ layer contains the blood vessels that nourish the eye.

middle

Nearsighted individuals suffer from _____________, which is when the eyeball is elongated.

myopia

Visual nerve pathways bring nerve impulses from the retina to the visual centers in the _____________ lobe of the brain.

occipital

The cranial nerve that is formed from sensory fibers from the retina is the _____________ nerve.

optic

The retina sends sensory information to the brain by the:

optic nerve

Pigment molecules are embedded within the _____________ segment of the rods and cones.

outer

The three sections of the ear are: _____________ ear, _____________ ear and _____________ ear.

outer; middle; inner

The _____________ window is a membrane attached to the stapes and the bone of the inner ear.

oval

Receptors that are stimulated by damage to tissues are _____________ receptors.

pain or nociceptor

The fluid within the bony labyrinth is called _____________. The fluid within the membranous labyrinth is called _____________.

perilymph; endolymph

The auditory (Eustachian) tube connects the middle ear to the _____________.

pharynx

Receptors that are only found in the eye are:

photoreceptors

The receptors that can be damaged by staring directly into the sun are the _____________.

photoreceptors

The following are components of the outer ear:

pinna external auditory canal

Specialized sensory receptors, unable to send action potentials, use a system to transduce stimuli involving _____________ potentials.

receptor

The _____________ is the inner layer of the eye and is located in the posterior compartment.

retina

The cornea, lens and fluids in the eye chambers help to focus an image on the _____________.

retina

The image formed on the ______________ is upside down and reversed from left to right.

retina

When a rod absorbs light, _____________ splits into opsin and retinal, and triggers a cascade of events that closes the ion channels in the rod cell's plasma membrane.

rhodopsin

The fovea centralis is the area of sharpest vision because it lacks _____________.

rods

What type of photoreceptor is more sensitive to light and can, therefore, provide vision in dim light?

rods

Which type of photoreceptor provides black/white/gray vision?

rods

Of the photoreceptors, the _____________ are more sensitive to light than the _____________ and therefore can provide vision in dim light.

rods; cones

The _____________ window is a membrane that helps to diminish pressure waves in the inner ear.

round

The protective, fibrous, outer posterior layer of the eye is the:

sclera

The outer layer of the eye consists of the tough white colored _____________ and the anterior transparent _____________.

sclera; cornea

General Sensory receptors relay information to the _____________ area of the cerebral cortex.

somatosensory

The delicate fibers called _____________ attach the lens to the ciliary body.

suspensory ligaments

Chemoreceptors can be found in places like the:

taste buds nose

The hearing centers of the brain are located in the:

temporal lobe

Sensory receptors send impulses to specific brain areas after relaying them through the:

thalamus

The blind spot of the eye is:

the region where the optic nerve leaves the retina

The _____________ membrane is where the outer ear ends and the middle ear begins.

tympanic

The semicircular canals and the _____________ of the inner ear are involved in equilibrium, while the _____________ is involved in hearing.

vestibule; cochlea

A process by which the eye adjusts and is able to focus on objects close and far away, always producing a sharp image is known a:

visual accommodation

The transparent, jellylike fluid that fills the posterior compartment is called _____________ humor.

vitreous

Match the eye disorders with their correct description:

diabetic retinopathy --> Damage to the retinal blood vessels Cataract --> Cloudiness of the lens Glaucoma --> High intra ocular pressure due to excess aqueous humor macular degeneration --> Blurred vision due to retinal photoreceptors being destroyed

the auditory canal is lined with specialized sweat glands that produce cerumen, more commonly known as:

earwax

The ear is the organ that functions in the sense of hearing. It also functions in the sense of _____________.

equilibrium or balance

The center of the macula lutea where vision is the sharpest is the:

fovea centralis

The slightly depressed center region of the macula that produces the sharpest vision is known as the

fovea centralis

The innermost layer of the retina contains _____________ whose fibers become the optic nerve.

ganglion cells

Cells found in the layers of the retina are:

ganglion cells rods and cones bipolar cells

Tears are produced by the

lacrimal apparatus

The accessory organ of the eye that produces tears is the:

lacrimal gland

Place these structures in the correct order that light rays travel through to focus an image on the retina:

1. cornea 2. aqueous humor 3. lens 4. vitreous humor 5. retina

Name in order starting from the tympanic membrane (ear drum) to the oval window, the three auditory ossicles:

1. malleus 2. incus 3. stapes

Place the structures in the proper order that impulses travel from the optic nerve to the occipital lobe:

1. optic nerve 2. optic chiasma 3. optic tract 4. thalamus 5. occipital lobe

Which area of the retina is lacking photoreceptors?

Blind spot

Which sensory receptors are correctly matched to the stimulus it responds to?

Chemoreceptor - Concentrations of chemicals Photoreceptors - Light energy

The fluid of the anterior cavity of the eye is called the _____________ humor.

aqueous

Unlike rods, there are _____________, _____________, and _____________ cone pigments.

blue; green; red

The middle layer of the eye is composed of the:

choroid iris ciliary body

The three layers of the eye are:

choroid retina sclera

The _____________ body contains muscles that surround the lens and controls vision.

ciliary

The shape of the lens is controlled by the _____________ muscles.

ciliary

The lens is attached to the _____________ which allows for accommodation.

ciliary body

The thickened part of the choroid layer behind the iris that holds the lens in place is the _____________.

ciliary body

The photoreceptors that provide color vision are called _____________ cells; the ones that provide black/gray/white vision are called ______________ cells.

cone; rod

The fovea centralis contains densely packed cells called _____________ making this area the sharpest for bright-light vision.

cones

The retina contains photoreceptors called:

cones rods

A transparent mucus membrane that folds back to cover the anterior portion of the eye is known as the:

conjunctiva

The mucus membrane of the inner layer eyelids is called the _____________.

conjunctiva or palpebrae

The _____________ is a pigmented smooth muscle structure that regulates the pupil.

iris