ANSC220 - Sensory (Exam #2)

Nictitating Membrane

Third eyelid that helps clean out and protect eye

Granula Iridica

Reduces glare and increases visual clarity

Tapetum Lacidum

Green reflective material in the back of the eye; Found in cats

Retina

Rod and cone cells; Where light information is collected and sent

Choriod

Collection of blood cells in the eye

Vitreous Humor

Gel-like substance in vitreous chamber of eye

Cornea

First area of eye that light travels through

Iris

Smooth muscle that allows eye to change size pupil

Lens

Reflects light onto back of retina; Changes shape to accomodate distance of light

Ciliary Body

Smooth muscle connected to lens by suspensory ligaments that changes shape of lens

Pupillary Constriction

Parasympathetic circular muscle

Pupillary dilation

Sympathetic radial muscle

Rod cells

Provide light vision based on intensity, not color

Cone cells

Provide color vision

Rhodopsin photopigment

Absorbs all wavelengths of light

Scotopsin Photopigment

Detects red, green, and blue wavelengths

Semicircular Canals

Detect changes in head position and acceleration of head

Ampulla

Flaring out ends of semicircular canals

Cupula

Tissue that sticks up in ampulla that contains hair cells

Otolith organs

Detect changes in head position and linear acceleration

Otoliths

Provide weight to fluid overlaying hair cells

2 Otolith organs

Utricle and Saccule

Tympanic Membrane

Vibrates in response to sound waves; Provides sound intensity and pitch information

Intensity

Loudness of sound; Depends on sound wave amplitude (height)

Pitch

Tone of sound; Depends on sound wave frequency

Ossicles

Three small bones in mammals that transfer vibrations from tympanic membrane to cochlea oval window

Columella

One bone in reptiles/amphibians/birds that transfers vibrations from tympanic membrane to cochlea oval window

Order of Ossicles

Malleus, Incus, Stapes

Cochlea

Coiled tubular system with three fluid-filled compartments

Scala Vestibuili

Upper compartment of cochlea

Scala media/Cochlear duct

Middle compartment of cochlea

Scala tympani

Lower compartment of cochlea

Organ of Corti

On top of basilar membrane in cochlear duct; Provides sense of hearing by transforming vibrations into action potentials

Gustatory cells

Chemoreceptors found in tongue

How many cells per taste bud?

50

Olfactory neurons

Chemoreceptor; Only type of neuron in mammals to undergo cell division during adult life

Olfactory Glomeruli

Mitral cells where olfactory neurons synapse

Olfactory neuron action potentials increase/decrease with concentration of odor molecule.

Increase

Vomeronasal Organ (VMO)

Additional sense organ in mammals and reptiles; Causes reproductive/social behaviors by reception of pheromones

Flehming Response

Opening the nasal passages so that pheromones stimulate VMO

Suspensory Ligament

A

Ciliary Body

B

Iris

C

Pupil

D

Lens

E

Cornea

F

Aqueous Humor

G

Vitreous Humor

H

Vitreous Chamber and Body

I

Choroid

J

Retina

K

Sclera

L

Optic Disc (“Bind spot”)

M

Optic Nerve

N

Optic Disc

O

Malleus

A

Incus

B

Scala Vestibuli

C

Cochlear Duct

D

Cochlea

E

Organ of Corti

F

Basilar Membrane

G

Scala Tympani

H

Tympanic Membrane

J

Semicircular Canals

A

Ampulla

B

Vestibular Apparatus

C

Utricle

D

Saccule

E

Tympanic Membrane

A

Ossicles

B

Semicircular Canals

C

Utricle and Saccule

D

Vestibular Apparatus

E