Lab 13 Flashcards
Cutaneous Sensations
- Tactile sensations
- Thermoreceptive Sensations (heat and cold)
- Pain Sensations
Tactile Sensations
- Touch
- Pressure
- Vibration
Touch
(a) Root Hair Plexuses
(b) Free (naked) Nerve Endings
(c) Merkel’s Discs
(d) Meissner’s Corpuscles (corpuscles of touch/tactile receptors)
(e) Ruffini
Pressure
(a) Free Nerve Endings
(b) Lamellated or Pacinian Corpuscles
Vibration
(a) Corpuscles of Touch (Meissner’s Corpuscles) (b) Lamellated Corpuscles (Pacinian Corpuscles)
Thermoreceptive Sensations (heat and cold)
- free nerve endings
- Krause’s end bulbs (cold)
Pain Sensations
(1) Somatic Pain
(2) Visceral Pain
nocieptors
pain receptors
most pain here is referred pain
visceral pain
Receptors
(1) Muscle Spindles
(2) Tendon Organs [Golgi Tendon Organs]
(3) Joint Kinesthetic Receptors
(4) Maculae and Cristae (in inner ear)
taste buds consist of 3 kinds of cells:
(1) Supporting (sustentacular) Cells
(2) Gustatory Cells (3) Basal Cells
are receptor cells themselves neurons
no
Location of Taste Buds
(1) Circumvallate (or vallate) Papillae
(2) Fungiform Papillae
(3) Filiform Papillae
(4) Foliate Papillae
all have taste buds
Circumvallate (or vallate) Papillae
most have taste buds; tip and sides
Fungiform Papillae
rarely have taste buds; anterior 2/3
Filiform Papillae
have taste buds; deep sides
Foliate Papillae
Special senses
Gustation (Taste)
Olfaction (Smell)
Vision (The Retina)
Hearing
Structure of Receptors
(1) Supporting (sustentacular) Cells
(2) Olfactory Receptor Cells with olfactory cilia
(3) Basal Cells
what type of neurons are olfactory receptor cells with olfactory cilia
bipolar
rich sebaceous glands
eyebrows
palpebrae
eyelids
ciliary glands
eyelashes
Lacrimal Apparatus
(1) Lacrimal Gland
(2) Lacrimal Ducts
(3) Lacrimal Punctum
(4) Lacrimal Canals (canaliculi)
(5) Lacrimal Sac (nasolacrimal duct)
Extrinsic Muscles of the Eye
lateral rectus
supeior oblique
all of the rest
lateral rectus
VI abducens
superior oblique
IV trochlear
all of the rest
3 occulomotor
Internal Anatomy of the Eye is divided into 3 layers:
Fibrous Tunic Vascular Tunic or Uvea
Nervous Tunic
extrinsic eye muscles attach here
sclera
1st element of the light focusing system
cornea
fibrous tunic
sclera and cornea
vascular tunic or uvea
choroid, cilary body, iris
pupil
nervous tunic
retina
- nonreflecting dark pigment
- vascular
choroid
what makes up the ciliary body
ciliary process, ciliary ring, ciliary muscles
when the circular muscles in the iris constrict, are they sympathetic or parasympathetic
parasympathetic
when the radial muscles in the iris dilate, are they sympathetic or parasympathetic
sympathetic
three zones of the retina named in the order in which they conduct impulses
- photoreceptor neurons
- bipolar neurons
- ganglion neurons
what percent are rod cells
95%
what percent are cone cells
5%
where is the anterior chamber
in front of the iris
where is the posterior chamber
behind the iris
what is the leading cause of blindness
glaucoma
what is glaucoma
too much intraocular pressure
lens becomes cloudy due to calcium deposits and the breakdown of proteins
cataracts
what do the lens do
focusing system
optic disc
blind spot
macula lutea
yellow spot
emmetropic eye
normal
myopic eye
nearsighted
hyperopic eye
farsighted
eye too short or refracting parts too weak (image behind
retina)
hyperopic eye
how do you correct farsightedness
convex lens
eye too long or refracting parts too strong (image in front of retina)
myopic move
how do you correct nearsightedness
concave lens
unequal curvature of the lens and/or cornea
astigmatism
- long tube coiled like a snail shell
- the organ of hearing
cochlea
what are the three canals of the cochlea
(1) vestibular canal (scala vestibuli) (2) tympanic canal (scala tympani)
(3) cochlear canal (scala media)
sensory portion of the cochlea
organ of corti
hangs over the organ of Corti
tectorial membrane
a complicated labyrinth of interconnected, fluid-filled chambers and canals
Inner Ear (internal ear) or Labyrinth
refers to orientation of body relative to the ground (gravity)
static equilibrium
maintenance of body position in response to sudden movements (rotation, acceleration, deceleration)
dynamic equilibrium
concerned with the sense of
equilibrium) kinetic/dynamic
semicircular canals
awareness of stimuli
sensation
interpretation of stimuli
perception
brain refers sensation to point of stimulus
projection
decrease in sensitivity to stimuli
adapatation
sensations that persist even after stimuli
after image
specific type of sensation felt
modality
receptors under touch
root hair plexus free naked nerve endings merkels discs meissner's corpuscles ruffini's corpuscles lamallated or pacicinian corpuscles
root hair plexus
network of roots around the hair, not encapsulated
where are the free naked nerve endings found?
everywhere in the skin and other tissues, not encapsulated
light touch, found in the epidermis, not encapsulated, free dendritic endings
merkel’s discs
fine and discriminatory touch, found in the dermis and hairless areas, encapsulated
meissner’s corpuscles
deep in the dermis, heavy and continuous touch, encapsulated
ruffinis corpuscles
deep in the dermis or subcutaneous, deep pressure
pacinian corpuscles
which two receptors deal with vibration?
pacinian and meissners (meissners detects a lower frequency and pacinian detects a higher frequency)
thermoreceptors
krause’s end bulbs
16,000 heat receptors in skin
cold receptors more abundant than heat
pain receptors are 27x more abundant than cold
detect cold, modified meissner’s, found in muscus membranes
krause’s end bulbs
what percent of taste is smell
80%
circumvallate
all have taste buds
fungiform
most have taste buds
filiform
rarely have taste buds
foliate
all have taste buds, most sensitive
what are the 5 tastes
sweet sour salty bitter umami
how long does it take for complete gustatory adaptation to take place?
1-5 minutes
how long does it take for partial gustatory adaptation to take place?
3-5 seconds
what taste are we most sensitive to?
bitter and sour
what taste are we least sensitive to?
sweet and salty
what is the pathway for gustatory
facial (VII) Glosso (IX) Vagus (X) Medulla thalamus parietal lobe
how fast is olfactory adaptation
50% within 1 second, 100% in 1 minutes
olfactory pathway
olfactory (I)
Olfactory bulb
olfactory tract
cerebral cortex
what are your palpebrae
eyelids
