Special Senses (+Lymphatic System) Flashcards
1
Q
What are the types of special sense receptors
A
Chemoreceptors, mechanoreceptors, and photoreceptors
2
Q
What is not a special sense
A
Touch
3
Q
What are the special senses and their receptors
A
Smell (chemoreceptors), taste (chemoreceptors), hearing (mechanoreceptors), equilibrium/balance (mechanoreceptors), and sight (photoreceptors)
4
Q
What is another word for smell
A
Olfaction
5
Q
What type of epithelium is the olfactory epithelium
A
Pseudostratified ciliated columnar
6
Q
Where do receptors synapse with interneurons of the brain for smell
A
Olfactory bulbs just under the frontal lobe
7
Q
What kind of cell is an olfactory receptor cell
A
Bipolar
8
Q
What are the PNS structures involved in smell
A
Olfactory epithelium, olfactory receptor cells, and cribriform plate of ethmoid bone
9
Q
What are the CNS structures involved in smell
A
Interneurons and glomeruli in the olfactory bulb
10
Q
What do interneurons send the signal through to get to the olfactory cortex of the brain
A
The olfactory tract
11
Q
What are the 4 steps to smell something
A
Mucus traps molecules from inhaled air, olfactory receptors are activated, synapse in a glomerulus that amplifies the signal, activated interneurons send signal through olfactory tract
12
Q
What distinguishes smells
A
Different patterns of chemical combinations (more chemicals makes a stronger smell)
13
Q
What papilla of the tongue contain taste buds
A
Vallate (circumvallate) and Fungiform
14
Q
What papillae of the tongue does not have taste buds
A
Filiform papillae
15
Q
How many taste buds does each papilla have
A
Over 100
16
Q
What is a taste bud made of
A
A taste pore with gustatory receptor cells with hair, supporting cells, and basal cells
17
Q
What do gustatory receptor cells do
A
The microvillus (hair) interacts with and binds to chemicals
18
Q
What is the function of supporting cells in taste pores
A
They are insulatory and help get rid of extra neurotransmitters
19
Q
What are basal cells in taste pores
A
Essentially stem cells that replace old/damaged cells every 7-10 days
20
Q
What is another term for the axons involved in taste
A
Taste fibers of the cranial nerve
21
Q
What are the steps to tasting
A
Molecules dissolved in saliva and present through taste pore, gustatory receptor cells are activated, axons transport the signal to the CNS
22
Q
What are the types of taste sensations
A
Sweet, sour, salty, bitter, umami/savory (can all be intermixed within one taste bud)
23
Q
What is flavor
A
A combination/pattern of taste, smell, and texture
24
Q
What is our dominant sense
A
Vision
25
What is the anatomy of the external eye
Iris, pupil, sclera, eyelid, palpebral fissure
26
What is another word for eyelid
Palpebra
27
What is the pupil
The whole within the iris that can change diameter
28
What is the palpebral fissure
Opening created when the eyelid is up
29
What is the lacrimal gland
Above the outer edge of the eye, serous cells produce tears
30
What are tears
Water and protein rich fluid that washes irritants away from the surface of the eye
31
How are tears drained from the eye
Lacrimal canaliculi (inner corner channel) to the lacrimal sac to the nasolacrimal duct to the nasal cavity
32
How many extrinsic muscles does the eye have and what is their function
6, they are skeletal muscle that attaches to the sclera (collagen fibers intermix) that work together to turn eyes to the same place at the same time
33
What is strabismus
Misaligned eyes (“cross eyed”)
34
What causes strabismus
Problems with one or more of the extrinsic eye muscles (length, attachment, paralyzed, weak, etc.)
35
What are the results of strabismus
Double vision, lack of stereoscopic (3D) vision, and amblyopia if untreated
36
What is amblyopia
Reduced vision in the weaker/lazy eye caused by strabismus because the cerebral cortex of the occipital lobe ignores the signals from that eye
37
What are the 3 layers of the eye
Fibrous tunic, vascular tunic, and sensory tunic
38
What are the 4 characteristics of the fibrous tunic of the eye
Outer layer that’s an extension of the dura mater, provides protection and mechanical support, avascular, made of the sclera and cornea
39
What is the sclera of the eye
The white, dense irregular CT that allows the eye to keep its shape
40
What is the cornea of the eye
Transparent dense regular CT that is continuous with the anterior sclera
41
What is the sclera covered with
Conjunctiva (mucous membranes made of stratified columnar epithelium and goblet cells) that’s sticky and vascularized
42
What are the characteristics of the vascular tunic
Lines the inner surface of the sclera, made of choroid, iris, and ciliary body
43
What is the choroid
Vascular, dark surface that absorbs excess light
44
What is the iris of the eye
Mainly smooth muscle that contracts/enlarges to change the size of pupil and regulate light entering the eye with melanocytes that produce brown pigment
45
What determines eye color
How much brown pigment someone has on the anterior region of their iris
46
What is the ciliary body
Smooth muscle that suspends and controls the shape of the lens to focus light on the back surface of the eye, has capillaries in it that produce aqueous humor
47
Describe the flow of aqueous humor
Ciliary processes produce it, it circulates through the anterior segment, then is removed through the scleral venous sinus (a blood sinus)
48
What is the sensory tunic of the eye
The retina
49
What are the 2 layers of the retina
The pigmented layer (lies against the choroid), and the neural layer (in contact with the lumen)
50
What is the pigmented layer of the retina
A single epithelial layer with melanin granules that absorbs light and nourishes the neural layer
51
What is the neural layer of the retina
Photoreceptor cells, bipolar cells, and ganglion cells
52
Which cells are activated by light in the eye
Photoreceptors (rods and cones)
53
What are the types of photoreceptors in the eye
Rods and cones
54
What are the 5 characteristics of rod cells
Most numerous, most sensitive to light (good for night vision), more in the sides of the eye, absorb photons of green light, responds to a broad range of light
55
What are the 3 characteristics of rod cells
Involved in color vision with 3 subtypes to respond to blue, red, and green light, work best in bright light (because not enough light to activate when dim), concentrated within the retina at the back of the eye
56
What do bipolar cells in the eye do
Activated by rods and cones, they activate ganglion cells
57
What do ganglion cells in the eye do
Activated by bipolar cells, their axons transmit electrical impulses to the brain through the optic nerve
58
How are photoreceptors activated
Different cells contain different pigments, these pigments are broken down by different wavelengths of light to activate the cell, the pigments rebuild to allow the cells to be reactivated
59
What is the optic disc
Where axons of ganglion cells leave the back of the eye causing a blind spot because there are no rods or cones
60
What is the macula lutea of the eye
Region at posterior pole of the eye, mostly made of cones, where you get the best image of something in bright light conditions
61
What is the fovea centralis
The very center of the macula latea, all cones, that has maximum visual acuity (images focus here when you look directly at them)
62
What are the 4 characteristics of the lens of the eye
Simple cuboidal epithelium along its anterior surface, concentric layers of fibers produced by epithelial cells (looks like an onion), changes shape to focus light (slight stretch like rubber ball), and separates the anterior segment from the posterior segment of the eye
63
What is an emmetropic eye
A normal eye (right shape and size) where light focuses on the retina
64
What is a myopic eye
Nearsighted, eye is too long so the image focused in front of the retina, concave lenses needed to correct
65
What is a hyperopic eye
Farsighted eye, eye is too short so image focuses behind the retina, needs convex lens to correct
66
What is presbyopia
The lens of the eye becomes less elastic as we age so we can’t accommodate or focus as well
67
What does LASIK surgery do
Reshapes the surface of the cornea using a layer to redirect light properly into the surface of the retina
68
What is an astigmatism
Abnormal shape of the cornea (like bulge) that causes light to diffract/scatter differently and produced two or more focal points (contacts weighted so their orientation is correct)
69
What is the anterior segment of the eye
Between the cornea and lens, with anterior and posterior chambers, contains aqueous humor
70
What is aqueous humor
Blood filtrate that supplies nutrients and oxygen to the lens and cornea
71
What is glaucoma
Condition where aqueous humor is drained slower than it’s produced, increasing the pressure and damaging the retina (could lead to blindness)
72
What is the posterior segment of the eye
Behind the lens, contains vitreous humor
73
What are the 4 characteristics of vitreous humor
Mostly water and some collagen fibers, behaves like partly set jello, supports the lens and retina, born with the amount of it you’re gonna have (problematic if it clouds)
74
What is a detached retina
A hole/small tear in the retina that allows vitreous humor to leak between the pigmented and neural layers + peel away from the choroid layer
75
What is the result of a detached retina
Photoreceptor cells die if the neural layer isn’t reattached to the nourishing underlying layer
76
What are the 3 regions of the ear and what do they do
External (collects and dampens sound - hearing), middle (amplifies, dampens, and transmits sound waves - hearing), and inner (sensory organs for hearing and equilibrium)
77
What are the structures of the external ear
The auricle (pinna), external acoustic meatus, and tympanic membrane (eardrum)
78
What is the auricle
The outer fleshy portion of the ear visible to us that provides protection and funnels sound into the external acoustic meatus
79
What is the external acoustic meatus
Air filled canal lined by stratified squamous epithelium (skin), with hairs and ceruminous glands
80
What do the hairs of the external acoustic membrane of the ear do
Keep insects and foreign materials out
81
What do the ceruminous glands of the external acoustic meatus of the ear do
Secrete cerumen (wax) that stops microorganisms from growing and prevents ear infections
82
What are the 4 characteristics of the tympanic membrane of the ear
It separates the external and middle ear, dense fibrous CT continuous with skin on the external side, mucous membrane on the middle ear side, and vibrates when hit by sound waves
83
What is a perforated eardrum
Membrane will heal but scar tissue can affect hearing
84
What are the characteristics of the middle ear
Air filled cavity that contains auditory ossicles and connects with the nasopharynx via the pharyngotympanic tube
85
What are the auditory ossicles
3 small bones (malleus, incus, and stapes) that transmit vibration from the tympanic membrane towards the inner ear
86
What does the pharyngotympanic tube do
Allows you to equalize pressure with the outside air
87
What is the pathway of vibration in the middle ear
Tympanic membrane to malleus to incus to stapes to oval window (connects with inner ear)
88
What are the skeletal muscles that attach to the auditory ossicles and what do they do
Muscles that tense up to dampen strong vibrations that could damage receptors in the inner ear, tensor tympani connects to the malleus and the stapedius (smallest skeletal muscle) attaches to the stapes
89
What are the windows of the middle ear
Vibrations from stales pass to fluid of inner ear from oval window (enters), and vibrations leave inner ear after activating receptors through the round window
90
What happens after vibrations exit the round window
The sound dissapates into the middle ear and air filled space
91
What are the characteristics of the inner ear
Fluid filled, has sensory receptors for hearing and equilibrium, made of membranous duct contained within the temporal bone
92
What is the bony labyrinth of the inner ear
Cave-like cavity that contains all other structure as well as nourishing perilymph fluid (like CSF)
93
What are the 3 regions of the bony labyrinth
Cochlea, vestibule, and 3 semicircular canals (all on different planes)
94
What are the characteristics of the membranous labyrinth of the inner ear
Water balloon like structure with endolymph fluid (reacts with receptor cells)
95
What are the regions of the membranous labyrinth
Cochlear duct (in cochlea), utricle (in vestibule), saccule (in vestibule), and semicircular ducts (in semicircular canals)
96
How does vibration travel through the cochlea
Enters oval window, goes through scala vestibuli (perilymph), then scala media (endolymph), crosses the basilar membrane (with sound receptors), into the scala tympani (perilymph), exists round window
97
What determines the pitch of sound
Where it crossed the basilar membrane (high frequency closer to base, low frequency further along)
98
What is the Spiral organ of Corti
Region of the cochlear duct on basilar membrane made of simple columnar epithelium and receptor cells
99
What are the structures of the Spiral organ of Corti
Hair cells (mechanoreceptors), stereocilia (hairs), tectorial membrane, fibers of the cochlear nerve (sensory neurons), and supporting cells (protect and support)
100
What do the stereocilia of the organs in the inner ear do
Organelles of hair cells that initiate an electrical impulse and activate the cell when bent
101
What is the tectorial membrane of the Spiral organ of Corti
Rigid sheet of collagen fibers that stereocilia are embedded in
102
What part of the Spiral organ of Corti moves when sound passes from the scala media to the scala tympani
The basilar membrane
103
What are the characteristics of the utricle and saccule of the inner ear
Membranous structure within bony Vestibule, utricle responds to horizontal movement, saccule responds to vertical movement, both have Macula
104
What is a macula
A region of sensory epithelium in the utricle and saccule that responds to linear movement
105
What are the structures of maculae
Supporting cells (simple columnar epithelium), hair cells, stereocilia, otolithic membrane, and otoliths
106
What is the otolithic membrane of the maculae
A flat jelly like disc that sits on the sensory epithelium and shifts in response to movement of endolymph to bend stereocilia
107
What are otoliths
Calcium carbonate crystals that add weight to the otolithic membrane to cause a more dramatic shift
108
What are the characteristics of the semicircular ducts
1 per canal, each with a barbell shaped Crista ampullaris (sensory epithelium that responds to rotational forces)
109
What are the structures of a Crista Ampullaris
Supporting cells (simple columnar epithelium), hair cells, stereocilia, and cupula
110
What is the cupula of a Crista Ampullaris
Gelatinous mass that tips under rotational forces and bends stereocilia
111
Which structures of the inner ear could cause vertigo
Maculae and Crista ampullares
112
What is vertigo
Feeling motion when you aren’t moving (could be caused by PNS and CNS
113
What in the inner ear could cause vertigo
Alcohol thins endolymph and impacts how it interacts with structures, viral/bacterial infection changes pressure, or otolith from maculae can dislodge and impact cupula of crista ampullaris (activate it when it shouldn’t be)
114
What does the lymphatic system do (3 things)
Transports: interstitial fluid built up in tissues back to blood stream, absorbed fats from fats from small intestine into the blood, and immune cells to and from the lymph nodes to the blood
115
Where does interstitial fluid come from
Leaks from blood capillaries
116
What is another word for interstitial fluid
Called LYMPH when in lymph vessels
117
Why do lymph nodes swell when sick
Because they fill with white blood cells
118
What are the primary structures of the lymphatic system
Lymphatic collecting vessels, nodes, trunks, and ducts
119
What is lymphedema
Swelling in regions of the body due to obstructions within lymphatic structures
120
What are the most common causes of lymphedema
In the US: removal/enlargement of lymph nodes, in 3rd world countries: obstruction (like parasite)
121
What is elephantiasis
Lymphedema caused by a parasite
122
What are the 3 characteristics of elephantiasis
Most common parasite nematode to cause it, larva are carried by mosquitoes, adult forms thrive in human lymphatic system (blocks lymph nodes and collecting vessels)
