Chapter 19 - Special Senses Flashcards
1
Q
Stimuli
A
Sensory information that initiate action potentials and perception in our bodies
2
Q
Sensation/Perception
A
our conscious awareness of stimuli
3
Q
Sensory Receptors
A
detect stimuli
4
Q
General Sense Receptors
A
sense temperature, pain, touch, stretch, and pressure
5
Q
Special Sense Receptors
A
sense gustation, olfaction, vision, equilibrium, hearing
6
Q
Transducers
A
change one form of energy into another ie. visual light receptors change light energy into electrical energy on the optic nerve
7
Q
Olfaction
A
-sense of smells
-can recognize 10 000 different smells
-nose contains 10 million receptors
8
Q
Olfactory Epithelium
A
consists of 3 types of cells
-receptors
-supporting
-basal
9
Q
Olfactory Receptor Cells
A
Detect odour
10
Q
Supporting Cells
A
-support, nourishment, insulation to receptor cells, odour-binding proteins
11
Q
Basal Cells
A
replace worn out olfactory receptor cells
12
Q
Olfactory (Bowman’s) Glands
A
mucous producing glands that moisten the epithelial surface and dissolve odorant molecules
13
Q
The Olfactory Pathway
A
olfactory receptor-> olfactory (CN I) nerves-> olfactory bulbs-> olfactory tract-> cerebral cortex-> olfactory cortex (temporal lobe)
14
Q
Gustation
A
-sense of taste
-receptors are located in adult taste buds
15
Q
Sweet
A
sugars
16
Q
Salty
A
Na+ and Cl-
17
Q
Sour
A
acids (H+)
18
Q
Bitter
A
alkaloids
19
Q
Umami
A
amino acids
20
Q
Taste Buds
A
-found in tongue, soft palate, epiglottis, pharynx
-3 types of papillae contain taste buds
21
Q
Papillae
A
4 types - elevations on the tongue where taste buds are found
22
Q
Filiform Papillae
A
-contain tactile receptors but NO TASTE BUDS
-increase friction between tongue and food so tongue can move food into oral cavity
23
Q
Fungiform Papillae
A
-5 taste buds each
-mushroom shaped elevations scattered over entire surface of the tongue
24
Q
Vallate (Circular) Papillae
A
-100-300 taste buds
-form an inverted V-shaped row at the back of the tongue
25
Foliate Papillae
-located on the lateral margins of the tongue
-most of their taste buds degenerate in early childhood
26
Gustatory Pathway
taste buds-> gustatory receptor-> CN VII (facial), IX (glossopharyngeal), X (vagus)-> gustatory nucleus (MO)-> thalamus-> Insula (cerebral cortex)-> primary gustatory cortex-> perception of taste
27
Accessory Structures
-prevent foreign objects from entering
-keep surface moist, clean, lubricated
28
Eyelid
-aka palpebrae
-anterior, moveable protective covering of the eye
29
Levator Palpebrae Superioris Muscle
weak twitch
30
Palpebral Fissure
space between eyelids
31
Lacrimal Caruncle
-contain sebaceous and sudoriferous glands
-pink bump containing ciliary glands that produce gritty secretion
32
Tarsal Plate
supports the eyelids
33
Tarsal Glands
-located in tarsal plates
-prevent tear overflow and sticking together of eyelids
-sebaceous glands
34
Chalazion
tumor or cyst in tarsal glands
35
Conjuctiva
lining over the anterior surface of the eye
36
Palpebral Conjuctiva
thin, protective mucous membrane
37
Eyebrows
-prevent sweat from dripping into the eye
38
Eyelashes
prevent foreign objects from entering eyes
39
Medial and Lateral Palpebral Commissures
corners of the eyes
40
Lacrimal Apparatus
-tears are produced in lacrimal gland
-dispersed across eye when we blink
-fluid enters the lacrimal puncta and drains into lacrimal canaliculi, collects in lacrimal sac
-drains through nasolacrimal duct
-enters nasal cavity
41
Orbital Fat
cushions the eye within the socket
42
Anterior Cavity
-in front of the lens
-contains circulating aqueous humor
43
Posterior Cavity
-behind the lens
-contains permanent vitreous humor
44
Aqueous Humor
-secreted by ciliary processes into the posterior chamber
-moves from posterior chamber, through the pupil, to the anterior chamber
-excess is reabsorbed by scleral venous sinus
45
Wall of the Eye
3 layers
46
Fibrous Tunic
-sclera
-cornea
-sclera venous sinus
47
Sclera
-support, protection, shape of the eye, muscle attachment
-the white of the eye
48
Cornea
-avascular collagenous tissue
-refracts light rays coming into the eye
49
Scleral Venous Sinus
-collects aqueous humor from the anterior chamber and delivers it to the bloodstream
50
Vascular Tunic
-choroid
-ciliary body
-iris
-pupil
-lens
51
Choroid
-vascular
-melanocytes (absorbs light)
-supplies nourishment to the retina
52
Ciliary Body
-melanocytes, aqueous humor
-smooth muscles and an inner secretory epithelium
-between choroid and iris
-secretes aqueous humor
-holds suspensory ligaments that change the shape of the lens
53
Iris
-coloured portion of the eyeball
-two smooth muscles that control pupil diameter
54
Pupil
-opening in the iris that regulates the amount of light that enters
55
Lens
changes shape to focus light on the retina
56
Inner Tunic
-macula lutea
-fovea centralis
-optic disc
-hyaloid canal
57
Retina
-converts light into impulses
-layer at the back of the eyeball
58
Pigmented Layer
-melanin helps absorb stray light rays
-provides vitamin A for photoreceptors
-passes on nutrients and oxygen
59
Neural Layer
-contains photoreceptors that convert light into impulses
-3 layers
60
Photoreceptor Cells
-outermost layer composed of rods and cones
61
Rods
-night vision
62
Cones
-precise and colour vision
63
Bipolar Cells
synapse with photoreceptors and ganglion cells
64
Horizontal Cells
some lie between photoreceptors and bipolar cells
65
Ganglion Cells
-innermost layer of the retina
-axons of these cells leave the retina and form the optic nerve (CN II)
66
Amacrine Cells
-between bipolar cells and ganglion cells
-help process and integrate visual info
67
Are there more rods or cones in human eyes?
20x more rods than cones
68
Optic Disc
-"blind spot"
-located on the retina
-lacks photoreceptors
-located where ganglion cells exit to form optic nerve
-also where blood vessels enter/exit retina
69
Fovea Centralis
-depression in the retina
-contains the highest amount of cones and almost no rods
-area of sharpest vision
70
Macula Lutea
-houses fovea
-yellow region
-sharp detailed vision
-located on retina
71
Visual Pathway
bipolar cells->optic nerve (CN II)->optic chiasm->optic tract->lateral geniculate nucleus-thalamus->primary visual cortex of the occipital lobe->superior colliculi (visual reflexes)->pretectal nuclei (accommodation of reflexes)
72
External Ear
collects sounds waves
73
Pinna (aka auricle)
-directs sound waves into the ear canal
74
External Auditory Canal
-funnels sound waves to the tympanic membrane
-bony tube
75
Ceruminous Glands
-produces a waxlike secretion called cerumen
-combines with dead skin cells to from ear wax
-helps reduce infection
76
Tympanic Membrane (aka eardrum)
-vibrates when hit with sound waves
-transmit sound energy into middle and inner ear
77
Umbo
-central point of maximum depression
-marks the end of the manubrium of the malleus
78
Middle Ear
-transmits sound waves to the oval window
-small, air-filled cavity in the temporal bone
79
Ossicles
-malleus, incus, stapes
-amplify the vibrations
-footplate of the stapes fits into the oval window
-initiate waves in the inner ear fluid
80
Tensor Tympani and Stapedius Muscle
restrict ossicle movement when loud noises occur (protect sensitive receptors in the ear)
81
Auditory Tube (aka eustachian tube)
-opens to the nasopharynx from the middle ear
-normally closed
-air movement when yawning, chewing, swallowing allows pressure in ear to equalize
82
Inner Ear
-receptors for hearing and equilibrium
-aka labyrinth
-2 divisons
-located in temporal bone
83
Bony Labyrinth
-outer part that encloses an inner membranous labyrinth
-3 areas: semicircular canals, vestibule, cochlea
84
Membranous Labyrinth
-membrane lines, fluid filled tubes
-houses receptors for equilibrium and hearing
85
Perilymph
-within bony labyrinth
-space between bony and membranous
-similar composition of ECF and CSF
-suspends, supports, protects membranous labyrinth from wall of the bony labyrinth
-in scala vestibuli and tympani
86
Endolymph
-in membranous labyrinth
-low Na+ high K+ conc. similar to ICF
-in scala media
87
Semicircular Canals
-contain membranous labyrinth structure called semicircular duct
-fluid filled tubes that help with balance associated with circular motion
88
Vestibule
-contain saccule and utricle which sense linear motion
-utricle: horizontal motion
-saccule: vertical motion
89
Cochlea
-houses cochlear duct (membranous labyrinth)
-hearing
90
Macula
-sensory receptor located along internal walls of saccule and utricle
-composed of hair cells and supporting cells
91
Hair Cells
-sensory receptors of the inner ear for hearing and equilibrium
-release NTs to sensory neurons
92
Stereocilia and Kinocilium
-line apical surface of each hair cell
-release NTs when bent certain directions
-embedded in gelatinous layer
93
Otoliths
-also in gel layer (otolithic membrane)
-calcium carbonate crystals
94
Modiolus
three turns of the cochlea around one bony core
95
Coclea Divisions
-divided into three channels (scala)
96
Scala Media
-aka cochlear duct
-roof: vestibular membrane
-floor: basilar membrane
-filled with endolymph
97
Scala Vestibuli
-adjacent to vestibular membrane
-perilymph
98
Scala Tympani
-adjacent to basilar membrane
-perilymph
99
Helicotremma
-interconnect scala vestibuli and tympani at the apex of the cochlea
100
Organ of Corti
-the sensory structure for hearing
-hair cells and supporting cells rest on basilar membrane
-single row of inner hair cells and three rows of outer hair cells (alter response to sound)
101
Tectorial Membrane
-stereocilia and kinocilium on apical hair cell surface housed in this gelatinous structure
102
Spiral Ganglion
-house cell bodies of sensory neurons
103
Auditory Pathway
spiral ganglia->cochlear nuclei (MO)-> lateral lemniscus->inferior colliculus-> superior olivary nucleus (pons)-> medial geniculate nucleus (thalamus)-> primary auditory area-> temporal lobe
104
Static (linear) Equilibrum
-maintain position of body relative to gravity
-receptors in saccule and utricle (macula)
105
Dynamic (rotational) Equilibrium
-maintain body position in relation to sudden movements
-receptors in semicircular canal (crista)
106
Semicircular Ducts
-ampulla
-crista
-capula
107
Ampulla
expanded region, farthest from utricle connection
108
Crista
-elevated region
-covered by hair and supporting cells
109
Cupula
-where crista embeds hair cells into this gelatinous dome
110
Equilibrium Pathway
vestibular ganglia-> vestibular branchof CN VIII-> vestibular nuclei-> inferior cerebral peduncles
111
Vestibular Nuclei
integrate info from vestibular, visual and proprioceptors and send commands
