Special Senses

Question 1

Eyeball has 6 primary components

Answer 1

• fibrious tunic
• vascular tunic
• nervous tunic (retina)
• lens
• anterior segment
• posterior segment

Question 2

Fibrous tunic consists of ..

Answer 2

• sclera
• cornea
• conjunctiva

Question 3

Sclera

Answer 3

avascular CT (white)

Question 4

Cornea

Answer 4

avascular CT (transparent)

Question 5

Conjuntiva

Answer 5

covers anterior surface of sclera, vascular mucous membrane (dilated vessels = bloodshot eyes)

Question 6

Vascular tunic parts

Answer 6

• choroid
• ciliary body
• iris
• pupil

Question 7

Choroid

Answer 7

contains melanin which prevents the reflection and scattering of light, highly vascular (posterior)

Question 8

Ciliary body

Answer 8

ciliary muscle and ciliary processes, which controls the space of the lens and secrete aqueous humor

Question 9

Iris

Answer 9

coloured part of eye

Question 10

Pupil

Answer 10

hole in iris

Question 11

Nervous tunic (retina) consists of the

Answer 11

• outer pigmented layer
• inner neural layer
• fovea centralis
• optic disc

Question 12

Inner neural layer of retina’s 3 layers

Answer 12

• photoreceptors neurons
• bipolar cells
• ganglion cells

Question 13

2 types of photoreceptors

Answer 13

• rods (black and white)

- cones (color)

Question 14

Ganglion cells

Answer 14

axons from optic nerve (cranial nerve ll)

Question 15

Fovea centralis

Answer 15

where light is focused, area of greatest visual acuity, no rods only cones

Question 16

Optic disc

Answer 16

blind spot where blood vessels and optic nerve exit eye. no cones or rods

Question 17

Lens

Answer 17

avascular, transparent

Question 18

Cataracts =

Answer 18

clouding of lens

Question 19

Anterior chamber

Answer 19

anterior to lens, contains aqueous humor (fluid similar to plasma) which drains into sinus located at junction between cornea and sclera

Question 20

Posterior segment

Answer 20

posterior to lens, contains vitreous humor (gel like) and not replaced

Question 21

Structural features of the ear

Answer 21

• external ear
• middle ear
• inner ear
• cochlea

Question 22

External ear

Answer 22

conducts sound

Question 23

Parts of external ear

Answer 23

• auricle
• auditory canal (meatus)
• tympanic membrane (eardrum)

Question 24

Auricle/ pinna

Answer 24

elastic cartilage, covered in skin

Question 25

Middle ear functions to

Answer 25

conducts sound

Question 26

Parts of inner ear

Answer 26

- bony labyrinth - membranous labyrinth - vestibular nerve

Question 27

Bony labyrinth lined with ..

Answer 27

periosteum and contains perilymph

Question 28

Bony labyrinth contains the

Answer 28

- semicircular canals (equilibrium) - vestibule (equilibrium) - cochlea (hearing)

Question 29

Membranous labyrinth contains what lymph

Answer 29

contains endolymph

Question 30

Membranous labyrinth contains the ..

Answer 30

- semicircular duct - utricle and saccule - cochlear duct

Question 31

Semicircular duct

Answer 31

inside canals and connects with the utricle

Question 32

Utricle and saccule

Answer 32

inside vestibule

Question 33

Cochlear duct

Answer 33

inside cochlea

Question 34

Cochlea is a

Answer 34

coiled structure (2.5 coils)

Question 35

Each cochlea coil has 3 channels

Answer 35

- scala vestibuli - scala tympani - scala media

Question 36

Scala vestibuli

Answer 36

upper; perilymph and part of bony labyrinth

Question 37

Scala tympani

Answer 37

lower; perilymph and part of bony labyrinth

Question 38

Scala media

Answer 38

(cochlear duct) middle. continuation of membranous labyrinth. contains endolymph in all three membranes

Question 39

Membranes of cochlea

Answer 39

- vestibular membrane - basilar membrane - tectorial membrane

Question 40

Vestibular membrane

Answer 40

separates the cochlear duct and scala vestibuli

Question 41

Basilar membrane

Answer 41

separates the cochlear duct and scala tympani

Question 42

Tectorial membrane

Answer 42

cover hair cells of spiral organ

Question 43

Receptors in inner ear

Answer 43

hair cells that synapse with neurons

Question 44

Hair cells in inner ear send..

Answer 44

impulses to brain via cranial nerve Vlll (vestibulcochlear nerve)

Question 45

Hairs of inner ear

Answer 45

cilia that extend to extend into endolymph

Question 46

Middle ear consist of the 3 auditory ossicles and what tube

Answer 46

- malleus (against tympanic membrane of external ear) - incus - stapes (against oval window of inner ear) - eustachian tube (auditory tube)

Question 47

Functions of the ear include

Answer 47

- conduction of sound | - hearing and equilibrium (inner ear)