S T U D Y G U I D E 9

1. Sensationsa. Match the structures with the statements that follow.

1) Cerebral cortex 2) Nerve fiber 3) Receptor

_____ Carries impulses. _____ Projects sensation back to region where

_____ Forms sensory impulses. impulses seem to originate.

_____ Interprets impulses as sensations. _____ Sensitive to a particular type of stimulus.

_____ Decreases impulse formation when _____ Exhibits adaptation.

repeatedly stimulated.

b. Define adaptation. ___________________________________________________________________________

_____________________________________________________________________________________________

2. General Sensesa. Match the responses with the statements that follow.

1) Cold receptors 4) Meissner’s corpuscles

2) Free nerve endings 5) Pressure receptors

3) Heat receptors

_____ Pain receptors. _____ Located in visceral organs.

_____ Touch receptors. _____ Located in superficial portion of dermis.

_____ Most sensitive to temperatures over 25°C. _____ Located in dermis and joints.

_____ Most sensitive to temperatures under _____ Temperature receptors closest to epidermis.

10°C. _____ Touch receptor abundant in hairless skin.

_____ May be located in epidermis. _____ Only in the skin.

b. What is referred pain? ________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

3. Taste and SmellWrite the terms described by the statements in the spaces at the right.

1) Organs containing taste receptors. ____________________________________________

2) Receptors located in nasal epithelium. ____________________________________________

3) Type of taste receptors at back of tongue. ____________________________________________

4) Type of taste receptors at sides and tip of tongue. ____________________________________________

5) Type of taste receptors at tip of tongue only. ____________________________________________

6) Type of taste receptors at sides of tongue only. ____________________________________________

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2

3

1

3

1

3

3

The decrease in impulse formation when a receptor is repeatedly stimulated by the

same stimulus.

2

2, 4

3

1

2

2, 5

2, 4

5

1

4

1, 3, 4

Projection of a pain sensation to a body part that is not involved in the source of

the stimulus.

Taste buds

Olfactory

Bitter

Salt

Sweet

Sour

4. Ear Structurea. Label the figure by placing the number of the structure in the space by the correct label.

_____ Auditory tube _____ Malleus _____ Stapes

_____ Auricle _____ Oval window _____ Tympanic cavity

_____ Cochlea _____ Round window _____ Tympanic membrane

_____ External auditory canal _____ Semicircular canals _____ Vestibulocochlear nerve

_____ Incus

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7

10

11

12

1

13

98

6

3

4

5

2

b. Write the terms that match the statements in the spaces at the right.

1) Part of the bony labyrinth that contains receptors for

a) hearing; ____________________________________________

b) static balance; ____________________________________________

c) dynamic balance. ____________________________________________

2) Fills membranous labyrinth. ____________________________________________

3) Fills bony labyrinth. ____________________________________________

4) Fills tympanic cavity. ____________________________________________

11

1

6

13

3

2

8

9

5

4

10

12

7

Cochlea

Utricle, saccule

Semicircular canals

Endolymph

Perilymph

Air

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c. Label the figure by placing the number of the structure in the space by the correct label.

_____ Basilar membrane

_____ Cochlear duct

_____ Cochlear portion of

the vestibulocochlear

nerve

_____ Hair cells

_____ Organ of Corti

_____ Scala tympani

_____ Scala vestibuli

_____ Tectorial membrane

_____ Vestibular membrane

5. Hearinga. Write the terms that match the statements in the spaces at the right.

1) Receptor organ for hearing. ____________________________________________

2) Receptor cells for hearing. ____________________________________________

3) Carry vibrations from eardrum to perilymph. ____________________________________________

4) Directs sound waves to tympanic membrane. ____________________________________________

5) Contains fibers of increasing length. ____________________________________________

6) Membrane-covered opening into scala tympani. ____________________________________________

7) Membrane struck by sound waves. ____________________________________________

8) Membrane that determines pitch of sound. ____________________________________________

9) Membrane contacting hairs of receptor cells. ____________________________________________

10) Allows air to enter tympanic cavity. ____________________________________________

b. Write the terms that complete the sentences in the spaces at the right.

Sound waves enter the ____1___ and strike the

____2___ , causing it to vibrate. This vibration is

transmitted by the ____3___ to the ____4___ that fills

the scala vestibuli and scala tympani. Oscillating

movements of this fluid cause comparable vibrations

of portions of the ____5___ membrane and the

____6___ that rests upon it. This causes the hair cells

to contact the ____7___ , which stimulates them to

form ____8___ that are carried to the brain by the

____9___ nerve. The hearing centers in the ____10___

lobes interpret these impulses as sound sensations.

4

2

3

5

7

8

1

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1) ___________________________________________

2) ___________________________________________

3) ___________________________________________

4) ___________________________________________

5) ___________________________________________

6) ___________________________________________

7) ___________________________________________

8) ___________________________________________

9) ___________________________________________

10) ___________________________________________

7

3

9

6

5

8

1

4

2

Organ of Corti

Hair cells

Ear ossicles

External auditory canal

Basilar membrane

Round window

Tympanic membrane

Basilar membrane

Tectorial membrane

Auditory tube

External auditory canal

Tympanic membrane

Ear ossicles

Perilymph

Basilar

Organ of Corti

Tectorial membrane

Impulses

Vestibulocochlear

Temporal

6. EquilibriumWrite the terms that match the statements in the spaces at the right.

1) Receptor organ for static equilibrium. ____________________________________________

2) Chambers containing receptors for static

equilibrium. ____________________________________________

3) Force stimulating hair cells of macula. ____________________________________________

4) Receptor organ for dynamic equilibrium. ____________________________________________

5) Locations of receptor organs for dynamic

equilibrium. ____________________________________________

6) Fluid moving cupula when head is turned. ____________________________________________

7) Part of brain controlling equilibrium. ____________________________________________

7. Accessory Structures of the EyeWrite the terms that match the statements in the spaces at the right.

1) Lines eyelids and covers anterior sclera. ____________________________________________

2) Group of muscles that move the eye. ____________________________________________

3) Secretes tears. ____________________________________________

4) Collect tears at inner corner of eye. ____________________________________________

5) Carries collected tears into nasal cavity. ____________________________________________

8. Eye Structurea. Write the terms that match the statements in the spaces at the right.

1) Fills anterior cavity. ____________________________________________

2) Pigmented layer of the eyeball. ____________________________________________

3) Substance holding retina against choroid. ____________________________________________

4) Opening in center of iris. ____________________________________________

5) Fluid mostly responsible for internal pressure

in eye. ____________________________________________

6) Protective outer fibrous coat of eye. ____________________________________________

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Macula

Utricle, saccule

Gravity

Crista ampullaris

Semicircular canals

Endolymph

Cerebellum

Conjunctiva

Extrensic eye muscles

Lacrimal gland

Canaliculi

Nasolacrimal duct

Aqueous humor

Choroid

Vitreous humor

Pupil

Aqueous humor

Sclera

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b. Label the figure by placing the number of the structure in the space by the correct label.

_____ Aqueous humor in anterior cavity _____ Optic disk

_____ Choroid coat _____ Optic nerve

_____ Ciliary body _____ Pupil

_____ Conjunctiva _____ Retina

_____ Cornea _____ Sclera

_____ Fovea centralis _____ Suspensory ligaments

_____ Iris _____ Vitreous humor in posterior cavity

_____ Lens

1

2

3

4

5

6

7

8

915

14

13

12

11

10

9. VisionWrite the terms that match the statements in the spaces at the right.

1) Contains photoreceptors. ____________________________________________

2) Site of direct vision. ____________________________________________

3) Clear window through which light enters eye. ____________________________________________

4) Controls amount of light entering eye. ____________________________________________

5) Focuses light rays on retina. ____________________________________________

6) Layer containing blood vessels. ____________________________________________

7) Changes shape of the lens. ____________________________________________

8) Retinal area lacking photoreceptors. ____________________________________________

9) Causes greatest bending of light rays. ____________________________________________

7

15

9

8

4

13

3

6

11

12

5

14

10

2

1

Retina

Fovea centralis

Cornea

Iris

Cornea and lens

Choroid

Ciliary body

Optic disk

Cornea

10) Absorbs excessive light in eye. ____________________________________________

11) Receptors for dim light vision. ____________________________________________

12) Receptors for color vision. ____________________________________________

13) Receptors absent in fovea. ____________________________________________

14) Carries impulses from retina to brain. ____________________________________________

15) Where medial nerve fibers cross over. ____________________________________________

16) Light-sensitive pigment in rods. ____________________________________________

17) Colors of light absorbed by three types of cones. ____________________________________________

____________________________________________

____________________________________________

18) Vitamin required for rhodopsin synthesis. ____________________________________________

10. Disorders of Hearing and VisionWrite the disorders described in the spaces at the right.

1) An infection called “pink eye.” ____________________________________________

2) Cloudiness of the lens. ____________________________________________

3) Acute infection of the middle ear. ____________________________________________

4) Deafness due to exposure to loud noises. ____________________________________________

5) Deafness correctible by hearing aids. ____________________________________________

6) Results from unequal curvatures of lens or cornea. ____________________________________________

7) Corrected by convex lenses. ____________________________________________

8) Corrected by concave lenses. ____________________________________________

9) Decreased elasticity of the lens. ____________________________________________

10) Nausea due to repeated stimulation of equilibrium

receptors. ____________________________________________

11) Group of disorders producing nausea, dizziness,

and tinnitis. ____________________________________________

12) Cancer of immature retinal cells. ____________________________________________

13) Caused by excessive intraocular pressure. ____________________________________________

14) Crossed eyes. ____________________________________________

11. Clinical Applications a. An older patient calls the office and complains of pain at the base of the neck, left shoulder, and left

arm. What is the probable cause of the pain? _______________ Why was the pain localized in these

areas? _______________________________________________________________________________________

_________________________________________________________________________________________________________

What would you advise the patient to do? ______________________________________________________

b. An audiometry test verifies that a college student has a decreased sense of hearing. Discussion brings

out that he has been working as an audio engineer at a local disco for three years. What relationship

probably exists between his job and his hearing loss? ____________________________________________

_________________________________________________________________________________________________________

_________________________________________________________________________________________________________

Choroid

Rods

Cones

Rods

Optic nerve

Optic chiasma

Rhodopsin

Red

Green

Blue

Vitamin A

Conjunctivitis

Cataract

Otitis media

Nerve deafness

Conduction deafness

Astigmatism

Farsightedness

Nearsightedness

Presbyopia

Motion sickness

Labyrinthine disease

Retinoblastoma

Glaucoma

Strabismus

Heart attack

Sensory impulsed from the heart use nerve serving neck, shoulder, and arm.

Call 911 or go to the emergency room.

The loud music has probably caused partial

nerve deafness.

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