Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
155 Cards in this Set
- Front
- Back
|
General senses
|
-receptors that are widely distributed throughout the body
-skin, various organs and joints |
|
|
Special senses
|
-speicalized receptors confined to structure in the head
-eyes, ears, nose and mouth |
|
|
Sensory receptors
|
-specialized cells or multicellular structures that collect information from the environment
-stimulate neurons to send impulses along sensory fibers to the brain |
|
|
Sensation
|
a feeling that occurs when brain becomes award of sensory impulse
|
|
|
Perception
|
a person's view of the stimulus; the way the brain interprets the information
|
|
|
Receptor types
|
Chemoreceptors, pain receptors (nociceptors), themoreceptors, mechanoreceptors, photoreceptors
|
|
|
Chemoreceptors
|
respond to changes in chemcial concentrations
|
|
|
Pain receptors
|
aka nociceptors
respond to tissue damage |
|
|
Thermoreceptors
|
respond to temperature changes
|
|
|
Mechanoreceptors
|
respond to mechanical forces
|
|
|
Photoreceptors
|
responds to light
only in eye |
|
|
Sensory Impulses
|
-stimulation of receptor causes local change in its receptor potential (similiar to local action potential)
-a graded electrical current is generated that reflects intensity of stimulation (similar to threshold) -if receptor is part of a neuron, the membrane potential may generate an action potential -if receptor is not part of a neuron, the receptor potential must be transferred to a neuron to trigger an action potential (all-or-none principle) -peripheral nerves transmit impulses to CNS where they are analyzed and interpreted in the brain |
|
|
Projection
|
-process in which the brain projects the sensation back to the apparent source
-it allows a person to pinpoint the region of stimulation |
|
|
Sensory adaption
|
-ability to ignore unimportant stimuli
-involves a decreased response to a particular stimulus form teh receptors (peripheral adaptation) or along the CNS pathways leading to the cerebral cortex (central adaptation) -sensory impulses become less frequent and may cease -stronger stimulus is required to trigger impulses |
|
|
Def: Genral Senses
|
Senses associated with skin, muscles, joints, and viscera
|
|
|
3 groups of General senses
|
1. exteroceptive senses (exteroceptors) outside
2. Visceroceptive senses (interoceptors) inside 3. Proprioceptive senses (Speacialized) |
|
|
Exteroceptive senses
|
Senses associated with body surface such as touch, pressure, temporature, and pain
|
|
|
Visceroceptive senses
|
Senses associated with changes in the viscera such as blood pressure stretching blood vessels and ingestion of a meal
|
|
|
Proprioceptive Senses
|
Senses associated with changes in muscles and tendons such as at joints
eg.( Touching your nose with your eyes closed) |
|
|
3 types of Touch and Pressure Senses
|
-Tactile (Meisner's) corpuscles
-Lamellated (Pacinian ) corpuscles -Free Nerve Endings |
|
|
Char. of Free nerve endings
|
-Common in epithelial tissues
- Simplest receptors - Sense itching |
|
|
Tactile Corpuscles
|
- Aka Meisner's
- Aboundant in hairless portions of skin and lips - Detect fine touch; distinguish between two points on the skin |
|
|
Lamellated Corpuscles
|
- Aka Pacinian
- Common in deeper subcutaneous tissues, tendons and ligaments - Detect heavy pressure and vibrations |
|
|
3 Types of temporature Receptors
|
Warm receptors
Cold receptors Pain receptors |
|
|
Warm receptors
|
- Sensitive to temp. above 25*C (77*F)
- Unresponsive to temp. above 45*C (113*F) |
|
|
Cold Receptors
|
-Sensitive to temp. between 10*C (50*F) and 20*C (68*F)
|
|
|
Pain Receptors
|
Respond to temp below 10*C
Respond to temp above 45*C |
|
|
Sense of Pain Characteristics
|
- Free nerve endings
- Widely Distributed - Nervous tissue of brain lacks pain receptors - stimulated by tissue damage, chemical, mechanical forces, or extremes in temperature - Adapt very little, if at all |
|
|
Visceral Pain Characteristics
|
- Pain receptors are the receptors in viscera whose stimulation produces sensations
- Pain receptors respond differently to stimulation - Pain receptors are not well organized - Pain receptors may feel as if coming from some other part of the body (Known as reffered pain) |
|
|
Referred Pain
|
May occur due to impulses from two regions following a common nerve pathway to the brain
|
|
|
2 types of Pain Nerve Pathways
|
- Acute pain fibers
- Chronic pain fibers |
|
|
Acute Pain Fibers
Characteristics |
- A-delta fibers
- Thin, myelinated - Conduct impulses rapidly - Associated with sharp pain - Well localized |
|
|
Chronic Pain fibers
Characteristics |
- C-fibers
- Thin, unmyelinated - Conduct impulses more slowly - Associated with dull, aching pain - Difficult to pinpoint |
|
|
All senses synapse in the thalamus except?
|
Smell
|
|
|
Thalamus
|
Allows person to be aware of pain
|
|
|
Cerebral cortex
|
- Judges intensity of pain
- Locates source of pain - Produces emotional and motor responses to pain |
|
|
Pain inhibiting substances
|
Enkephalins
Seratonin Endorphins |
|
|
Main types of Proprioceptors
|
- Pacinian corpuscles - In joints
- Muscle Spindles - In skeletal muscles (considered stretch receptors) - Golgi tendon Organs - In tendons ( considered stretch receptors) |
|
|
Mechanoreceptors
|
- Send information to spinal cord and CNS about body position and length, and tesion of muscles
|
|
|
Visceral Senses
|
-Receptors in internal Organs
- Convey information that includes the sense of fullness after eating a meal as awell as the discomfort of intestinal gas and the pain that signals a heart attack |
|
|
Special senses
|
- Sensory receptors are within large, complex sensory organs in the head
- Smell in olfactory organs - taste in tastebuds (CN VII & CN IX) - Hearing and equilibrium in ears ( CN VIII) - Sight in eyes (CN II) |
|
|
Bitter Back Nine
|
Mnemonic for location of taste buds and the CN that run to the tongue. Bitter in the back of the tongue, Sweet,Salty,Sour up front
|
|
|
Olfactory Receptors
|
- Chemoreceptors
- Respond to chemicals dissolved in liquids |
|
|
Olfactory Organs
|
- Contain olfactory receptors and supporting epithelial cells
- Cover parts of nasal cavity, superior nasal conchae, and a portion of the nasal septum |
|
|
Visual accessory organs
|
-eyelids
-lacrimal apparatus -extrinsic eye muscles |
|
|
what are the four layers that the eyelid is composed of:
|
-skin
-muscle -connective tissue -conjunctiva |
|
|
eyelid is also referred to as
|
-palpebra
|
|
|
orbicularis oculi
|
closes the eyelid
|
|
|
levator palpebrae superioris
|
open the eyelid
|
|
|
tarsal glands
|
secrete oil onto eyelashes
|
|
|
conjunctiva
|
mucous membrae; lines eyelid and covers portion of eyeball
ourtermost membrane (then the cornea) |
|
|
lacrimal gland
|
-lateral to eye
-secretes tears (tearing starts at upper corner and goes across the eye) |
|
|
canaliculi
|
collect tears
|
|
|
lacrimal sac
|
collects from the canaliculi
|
|
|
nasolacrimal duct
|
-collects from lacrimal sac
-empties tears into nasal cavity |
|
|
Structures of the eyelid
|
-4 layers
-orbicularis oculi -levator palpebrae superioris -tarsal glands -conjunctiva |
|
|
Lacrimal apparatus consists of
|
-lacrimal gland
-canaliculi -lacrimal sac -nasolacrimal duct |
|
|
extrinsic eye muscles
|
-superior recturs
-inferior rectus -medial rectus -lateral rectus -superior oblique -inferior oblique |
|
|
Superior rectus
|
rotates eye up and medially
|
|
|
Inferior rectus
|
rotates eye down and medially
|
|
|
Medial rectus
|
rotates eye medially
|
|
|
Lateral rectus
|
rotates eye laterally
|
|
|
Superior oblique
|
rotates eye down and laterally
|
|
|
Inferior oblique
|
rotates eye up and laterally
|
|
|
Olfactory Nerve Pathways
|
- Once olfactory receptors are stimulated, nerve impulses travel through
Olfactory nerves, olfactory bulbs, olfactory tracts, limbic system (for emotions) and olfactory cortex (for interpretation) *** No Thalamus Tract*** |
|
|
Olfactory stimulation
|
- Olfactory organs located high in the nasal cavity above the usual pathway of inhaled air
- Olfactory receptors undergo sensory adaptation rapidly - Sense of smell drops by 50% within a second after stimulation |
|
|
Olfactory Code
|
- Hypothesis
- Odor that stimulated by a distinct set of receptor cells and its associated receptor proteins |
|
|
Synesthesia
|
- Mixed-up senses
- The brain interprets a stimulus to one sense as coming from another. Eg. letters, numbers, or time evoke specific colors, or music may evoke a strong taste or odor. |
|
|
Taste buds
|
- Organs of taste
- Located on papillae of tongue, roof of mouth, linings of cheeks and walls of pharynx |
|
|
Taste receptors
|
- Chemoreceptors
- Taste cells - Taste hairs |
|
|
Taste cells
|
- modified epithelial cells that function as receptors
|
|
|
- Taste hairs
|
- microvilli that protrude from taste cells; sensitive parts of taste cells
|
|
|
Four types of taste
|
- Sweet
- Salty - Sour - Bitter |
|
|
Umami Aka OOMAMMA
|
- The taste of savory, pungent, meaty, or delicious.
- Japanese origin |
|
|
Structure of the eye
|
-hallow
-spherical -wall has three (3) layers: *outer fibrous tunic *middle cascular tunic *inner nervous tunic |
|
|
Outer tunic
|
-cornea
-sclera |
|
|
Cornea
|
-anterior portion
-transparent -light transmission -light refraction |
|
|
Sclera
|
-posterior portion
-opaque -protection |
|
|
Middle tunic
|
-iris
-ciliary body -choroid coat |
|
|
Iris
|
-anterior portion
-pigmented -controls light intensity |
|
|
Ciliary body
|
-anterior portion
-pigmented -holds lens -moves lens for focusing |
|
|
Choroid coat
|
-provides blood supply
-pigments absorb extra light |
|
|
Anterior portion of the eye is filled with
|
aqueous humor
|
|
|
Lens
|
-transparent
-biconvex -lies behind iris -largesly composed of lens fibers -elastic -held in place by suspensory liagments of ciliary body |
|
|
What sense is closely related to taste?
|
Smell
|
|
|
Whatstimulates Sweet taste?
|
Carbohydrates
|
|
|
What stimulates sour?
|
Acids
|
|
|
What stimulates salty?
|
Salts
|
|
|
What stimulates Bitter?
|
Many Organic Compounds
|
|
|
Spicy foods activate what?
|
Pain receptors
|
|
|
Sensory impulses from taste receptors travel along?
|
-Cranial nerves to
-Medulla Oblongata to -Thalumus to - Gustatory cortex (for interpretation) |
|
|
3 sections of the Ear
|
- External Ear
- Middle Ear - Inner Ears |
|
|
External Ear Includes
|
- Auricle
- External auditory meatus - Tympanic membrane |
|
|
Auricle (Function)
|
Collects sound waves
|
|
|
Ciliary body
|
-forms internal ring around the front of the eye
-ciliary process -ciliary process |
|
|
Ciliary processes
|
radiating folds
|
|
|
Ciliary muscles
|
contract and relax to move lens
|
|
|
accommodation
|
changing lens shape to view objects
|
|
|
Iris
|
-composed of connective tissue and smooth muscle
-pupil is hole in iris -dim light stimulates radial muscles and pupil dialtes -bright light stimulates circular muscles and pupil constricts |
|
|
Aqueous humor
|
-fluuid in anterior cavity of eye
-secreted by epithelium on inner surface of the ciliary body -provides nutrients -maintains shape of anterior portion of eye -leaves cavity through Canal of Schlemm |
|
|
Inner tunic
|
-retina
-contains visual receptors -continuous with optic nerve -ends just behind margin of the ciliary body -composed of several layers -macula lutea -fovea centralis -optic disc -vitreous humor |
|
|
macula lutea
|
yellowish spot in retina
|
|
|
fovea centralis
|
center of macula lutea; produces sharpes vision
|
|
|
optic disc
|
blind spot; contains no visual receptors
|
|
|
vitreous humor
|
thick gel that holds retina flat against choroid coat
|
|
|
Posterior cavity
|
-contains vitreous humor-thick gel that holds retina flat against choroid coat
|
|
|
Major groups of retinal neurons
|
-receptor cells, bipolar cells, and ganglion cells
-horizontal cells and amacrine cells |
|
|
receptor cells, bipolar cells, and ganglion cells
|
-provide pathway for impulses triggered by photoreceptors to reach the optic nerve
|
|
|
horizontal cells and amacrine cells
|
-modify impulses
|
|
|
Refraction
|
-bending of light
-occurs when light waves pass at an oblique angle into mediums of different densities |
|
|
Types of lenses
|
-convex
-concave |
|
|
Convex
|
-lenses cause light waves to converge
|
|
|
Concave
|
-lenses cause light waves to diverge
|
|
|
Focusing on retina
|
-as light enters eye, it is refracted by: convex surface of cornea, convex surface of lens
-image focused on retina is upside down and reversed from left to right |
|
|
External Auditory Meatus
(Function) |
- Lined with ceruminus glands
- Carries sound to tympanic membrane - Terminates with tympanic membrane |
|
|
Tympanic Membrane
(Function) |
- Vibrates in response to sound waves
|
|
|
Middle Ear includes?
|
- Tympanic cavity
- Auditory Ossicles - Oval Window |
|
|
tympanic cavity
|
- Air-filled space in temporal bone
|
|
|
auditory ossicles
|
- Vibrate in response to tympanic membrane
- Malleus, incus, and stapes - Hammer, anvil and stirrup |
|
|
Oval window
|
- Opening in wall of tympanic cavity
- Stapes vibrates against it to move fluids in the inner ear |
|
|
Auditory Tube
|
- Aka Eustachian tube
-Connects middle ear to throat - Helps maintain equal pressure on both side of tympanic membrane - Usually closed by valve like flaps in thoat |
|
|
Inner ear includes
|
- a complex system of labyrinths
- Osseous labyrith - Membranous labyrinth |
|
|
Osseous Labyrinth
|
- Bony Canal in temporal bone
- Filled with perilymph |
|
|
Membranous Labyrinth
|
- Tube within osseous labyrinth
- Filled with endolymph |
|
|
Visual receptors
|
-rods
-cones |
|
|
Rods
|
-long, thin projections
-contain light sensitive pigment called rhodopsin -hundred times more sensitive to light than cones -provide vision in dim light -produce colorless vision -produce outlines of objects |
|
|
Cones
|
-short, blunt projections
-contain light sensitive pigments called erythrolabe, chlorolabe, and cyanolabe -provide vision in bright light -produce sharp images -produce color vision |
|
|
Refraction disorders
|
-concave lens corrects nearsightedness
-convex lens corrects farsightedness |
|
|
Visual pigments
|
-rhodopsin
-pigments on cones |
|
|
Rhodopsin
|
-light-senstive pigment in rods
-decomposes in presences of light -triggers a complex series of reactions that initiate nerves impulses -impulses travel along optic nerve |
|
|
Pigments on cones
|
-each set contains different light-sensitive pigment
-each set is sensitive to difference wavelengths -color perceived depends on which sets of cones are stimulated *erythrolabe-responds to red *chlorolabe-responds to green *cyanolabe-responds to blue |
|
|
Stereoscopic vision
|
-provides perception of distance and depth
-results from formation of two slightly different retinal images |
|
|
Lifespand Changes
|
-age-related hearing loss due to:
*damage of hair cells in organ of Corti *degeneration of nerve pathways to the brain *tinnitus -age-related visual problems *dry eyes *floaters (crystals in vitreous humor) *loss of elasticity of lens *glaucoma *cataracts *macular degeneration |
|
|
Sense of equilibrium (2 types)
|
-static equilibrium
-dynamic equilibrium -CN VIII |
|
|
Static equilibrium
|
-vestibule
-sense position of head when body is not moving -i.e. sitting still but moving in a car |
|
|
Dynamic equilibrium
|
-semicircular canals
-senses rotation and movement of head and body -actual movement |
|
|
Vestibule
|
-Utricle
-Saccule -Macula |
|
|
Utricle
|
-communicates with saccule and membranous portion of semicircular canals
|
|
|
Saccule
|
-communicates with cochlear duct
|
|
|
Macula
|
-hair cells of utricle and saccule
-repsonds to changes in head position -bending of hairs results in generation of nerve impulses |
|
|
Semicircular Canals
|
-Three (3) canals at right angles
-ampulla -crista ampullaris |
|
|
Ampulla
|
-swelling of membranous labyrinth that communicates with the vestibule
|
|
|
Crista ampullaris
|
-sensory organ of ampulla
-hair cells and supporting cells -rapid turns of head or body stimulate hair cells |
|
|
Hearing loss
|
-can be due to interference with transmission of vibrations to the inner ear (conductive deafness) or damage to the cochlea or the auditory nerve and its pathways (sensorineural deafness)
|
|
|
Steps in the generation of sensory impulses from the ear
|
1. sound waves enter the external acoustic meatus
2. waves of changing pressures cause the tympanic membrane to reproduce the vibrations coming form the sound-wave source 3. auditory ossicles amplify and transmit vibrations to the perilymph in the scala vestibuli 4. movement of the stapes at the oval window transmits vibrations to the perilymph in scala vestibuli 5. vibrations pass through the vestibular membrance and enter the endolymph of the cochlear duct 6. different frequencies of vibration in endolymph move specific regions of the basilar membrane, stimulating speicific sets of receptor cells 7. a receptor cell depolarizes; its membrane becomes more permeable to calcium ions 8. in the presence of calciumions, vesicles at the base of the receptor cell release neurotransmitter 9. neuro transmitter stimulates the ends of nearby sensory neurons 10. sensory impulses are triggered on fibers of the cochlear branch of the vestibulocochlear nerve. 11. the auditory cortex of the temporal lobe interprets the sensory impulses |
|
|
3 parts of labyrinths
|
- Cochlea
- Semicircular canals - Vestibule |
|
|
Cochlea
|
- Functions in hearing
- Scala Vestibuli - Scala tympani - Cochlear Duct - Vestibular membrane - Basilar membrane |
|
|
Semicircular Canals
|
- Functions in equilibrium
|
|
|
Vesatibule
|
- Functions in equilibrium
|
|
|
Scala Vestibuli
|
-Located in the cochlea
- Upper compartment - Leads from oval window to apex of spiral part of the bony labyrinth |
|
|
Scala Tympani
|
- Lower compartment of cochlea
- Extends from apex of the cochlea to round window - Part of the bony labyrinth |
|
|
Cochlear Duct
|
- Portion of membranous labyrinth in the cochlea
|
|
|
Vestibular membrane
|
- Separates cochlear duct from scala vestibuli
|
|
|
Basilar Membrane
|
- Separates cochlear duct from scala tympani
|
|
|
Organ of Corti
|
- Group of hearing receptor cells (hair cells)
- On upper surface of basilar membrane - Different frequencies of vibration move different parts of basilar membrane - Partcular sound frequencies cause hairs of receptor cells to bend - Nerve impulse generated |
