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287 Cards in this Set
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provides the CNS with a link to the world. Includes sensory receptors, nerves, ganglia and motor endings
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Peripheral Nervous System
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respond to stimuli or environmental changes, classified by location, stimulus, and complexity.
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sensory receptors
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awareness to stimuli
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sensation
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interpret the meaning of stimulus
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perception
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location classification of sensory receptors
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-exteroreceptors
-interoceptors -proprioceptors |
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sensory receptors that:
-respond to external stimuli -near surface to detect light touch, pressure, pain, and temp -special senses |
Exteroceptors
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sensory receptors that:
-respond to internal stimuli form organs and vessels -monitor chemical changes, stretching, temperature |
Interoceptors (visceroceptors)
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sensory receptors that:
-respond to internal stimuli -in skeletal muscle, tendons, joints, and ligaments and connective tissue coverings of bones and muscles -monitor degree of stretch to advice brain of body movements |
proprioceptors
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stimulus type classification of sensory receptors:
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-mechanoreceptors (touch, pressure)
-thermoreceptors (temp changes) -photoreceptors (light energy) -cheoreceptors (chemicals in solution) -nociceptors (pain) |
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structural complexity classification of sensory receptors:
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-simple
-complex |
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sensory receptors that:
-have modified dendritic endings -are in skin, mucous membranes, muscles, and connective tissues -monitor general sensory info |
simple sensory receptors
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sensory receptors that:
-sense organs or localized collections of different cell types working together -make up special sense organs and general senses |
complex sensory receptors
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-most abundant in epithelial and connective tissues
-pain and temp changes |
free dendritic endings
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a dendritic ending + disc-shaped epidermal cells; light touch deep in epidermis
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merkel discs
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entwine in hair follicles; light touch (hair bending)
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root hair plexuses
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enclosed in connective tissue capsule; mechanoreceptors
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encapsulated dendritic endings
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just below epidermis; dendrites surrounded by schwann cells; light touch
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meissner's corpuscles
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variation of meissenr's corpuscles in mucous membranes
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krause's end bulbs
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deep in dermis and subcutaneous tissue; deep pressure, especially vibration. ("on-off" pressure) surrounded by up to 60 layers of schwan cells
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pacinian corpuscles
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found in dermis, subcutaneous tissue and joint capsules; similar to golgi tendon organs; respond to continuous pressure.
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ruffini's corpuscles
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proprioceptors in skeletal muscle; detect muscle stretch and initiates stretch reflex (knee jerk)
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muscle spindles (neuromuscular spindles)
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tendon proprioceptors; inhibit contraction of muscle
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golgi tendon organ
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why do golgi tendon organs inhibit contraction of muscles?
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they help monitor positions of joints
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proprioceptors monitoring stretch in articular capsule of synovial jints; we are aware of joint movements due to these
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joint kinesthetic receptors
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-energy of stimulus converted (transduced) into electrical event due to changes in membrane permeability of receptor region causing a graded receptor potential (like an EPSP)
-stimulus strength encoded in frequency of impulse transmission so CNS can determine intensity |
sensory receptor potentials
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receptor potentials decrease in some sensory receptors when stimulus is constent
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adaptation
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which senses adapt the fastest?
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pressure, touch, and smell
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bundles of peripheral axons enclosed by connective tissue
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nerve
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surrounds each axon; encloses myelin and/or neurilemma
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endonurium
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a bundle of nerve fiber
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fascicle
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the membrane around each fascicle
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perinurium
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membrane around the whole nerve
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epineurium
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contain sensory and motor fibers to and from CNS; includes most nerves
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mixed nerves
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brings sensory information to the CNS
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sensory (afferent) nerves
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bring information away from the CNS
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motor (efferent) nerves
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-somatic are afferent and efferent
-visceral are afferent and efferent |
mixed nerves
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collections of neuron cell bodies associated with nerves in the PNS
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ganglia
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is nerve regeneration good or poor?
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poor
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__ neurons cannot reduce
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mature
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damaged or compressed axons or peripheral nerves can ____
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regenerate
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-occurs as points distal to damage of axon cannot receive nutrients and disintegrate
-schwann cells and macrophages clean up debris |
wallerian degeneration
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schwann cells survive and proliferate due to ____ form the macrophages
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mitosis-stimulating chemicals
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___ guide regenerating axon sprouts across gaps
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schwann cells
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axons regenerate the a rate of __ per day; the greater the distance, the less chance of recovery due to adjacent tissues protruding into gaps
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1-5 mm
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even though nerves can regenerate they are __
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NEVER exactly the same
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CNS fibers never regenerate more than 1 mm because:
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-fewer macrophages, so clean up is slow
-oligodendrocytes in damaged area die and cannot guide regrowth -myelin sheaths of nearby axons contain growth inhibitors |
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__ bridge implants (fetal), activated macrophage transplants, antibodies to growth inhibitors, addition of growth factor may stimulate mature neurons to divide
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astrocyte
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what innervates the somatic fibers?
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somatic fibers
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-knob-like swellings of autonomic fibers at smooth and cardiac muscle
-mitochondria and synaptic vesicles (ACh or NE) -cleft wider and therefore response slower |
varicosities
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cranial nerves
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I-Olfactory nerve
II-Optic III-Oculomotor IV-trochlear V-trigeminal VI-abducens VII-Facial VIII-auditory (vestibulocochlear) IX-glossopharyngeal X-vagus |
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-cranial nerve responsible for sense of smell
-fivers run through the cribiform plate of the ethmoid bone |
Olfactory (I)
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-responsible for sense of vision
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Optic (II)
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where the optic nerves converge; SOME fibers cross over
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optic chiasma
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-primarily a motor nerve
-responsible for eye movement and proprioception (superior oblique muscle) |
trochlear (IV)
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-a mixed nerve; largest cranial nerve; pons to face
-ophthalmic, maxillary and mandibular divisions -sensory from the face -responsible for motor for chewing |
Trigeminal (V)
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inflammation of the trigeminal nerve
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trigeminal neuralgia (tic douloureux)
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-primarily motor
-responsible for extrinsic eye muscle that abducts the eyeball |
abducens (VI)
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-a mixed nerve
-has 5 branches (temporal, zygomatic, buccal, manndibular, and cervical) -responsible for facial expressions, propioception, taste, tears |
facial (VII)
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paralysis of facial virus on one side caused by herpes virus
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bell's palsy
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what does bells palsy look like?
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the face droops on one side
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-sensory
-responsible for hearing and balance |
auditory (VIII) vestbulocochlear
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-mixed nerve
-controls the tongue and pharynx -sensory for blood gases, regulate breathing and blood pressure |
glossopharyngeal (IX)
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-a mixed nerve
-only cranial nerve to thorax and abdomen -most motor fibers are parasympathetic efferentschest, lungs, abdominal organs -sensory tolaynyx and pharynx (speech and swallowing) -you cannot live if you lose this nerve!!! |
Vagus (X)
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-primarily motor
-joins with vagal fibers-motor to larynx, pharynx and soft palate; motor to trapezius and sternocleidomastoid |
accessory (XI)
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-primarily motor
-somatic fibers to tongue muscles, proprioceptor fibers for tongue movements in mixing food, swallowing, and speech |
hypoglossal (XII)
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there are __ pairs of mixed nerves that make up the spinal nerves
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31
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sensory fibers from peripheral receptors
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dorsal root
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motor fibers to skeletal muscles
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ventral root
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length of root increases toward inferior end of spinal cord; exits vertebral column
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cauda equina
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spinal nerves are only 12 cm long and then divide into rami; supplies anterior trunk and limbs
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ventral ramus
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supplies the posterior trunk
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dorsal ramus
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reenters vetebral canal to innervate meninges and blood vessels there
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meningeal branch
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joined to base of ventral rami of spinal nerves in thoracic region; contain autonomic fibers
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rami communicantes
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roots form __ and are sensory or motor
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spinal nerves
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rami are distal to and are lateral branches of spinal nerves and are __.
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mixed (sensory and motor)
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-all spinal nerves except thoracic have ventral (not dorsal) rami that branch and join one another lateral to teh vetebral column
-cervical, brachial, lumbar, and sacral -serve the limbs |
plexuses
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fibers of ventral rami cross over crisscross and each branch contains fibers from several spinal nerves; carried to body periphery via several different routs or branches. what does this do?
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prevents paralysis if one spinal segment or root damaged
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-deep in neck under sternocleidomastoid; formed by ventral rami of upper four cervical nerves
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cervical plexus
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supply skin only; sensory and motor nerves
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cutaneous nerves
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-gets most important of cervical plexus
-most input from C3 and C4 -supplies sensory fibers to diaphragm -if this area is damaged, repiratory arrest and ventilator neded |
phrenic nerve
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irritation of this nerve causes hiccups (diaphragm spasms)
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phrenic nerve
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-nerves of the upper limb; palpable superior to clavicle at lateral border of sternoclidomastoid
-ventral rami of C5-C8 and most of T1 |
brachial plexus
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five total; unite to form upper, middle, lower, trunks that divide into anterior and posterior divisions
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roots
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innervates the deltoid and teres minor, skin and joint of shoulder
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axillary nerve
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major lateral cord branch supplying motor fibers to arm flexors and cutaneous sensation of lateral forearm
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musculocutaneous nerve
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innervates skins and flexor muscles of the brachial plexus
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median nerve
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makes up the "funny bone"
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ulnar nerve
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largest branch of the brachial plexus; innervates the posterior skin of arm and extensor muscles of upper arm
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radial nerve
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-first four lumbar spinal nerves; lies in psoas major
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lumbar plexus
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largest nerve in the lumbar plexus, runs to thigh and divides; thigh flexors and knee extensors
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femoral nerve
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innervates adductor muscles of the leg
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obturator nerve
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-arises from spinal nerves L4-S4 caudal to lumbar plexus
-dozen named branches to buttocks and lower limb; perineum |
sacral plexus
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longest and thickest body nerve; innervates gluetus maximus to posterior thigh; hamstrings and part of adductor magnus
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sciatic nerve
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innervates the anterior, lower leg. breaks off into sural and plantar nerve
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tibial nerve
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innervates buttocks and tensor fascia latae
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superior and inferior gluteal nerves
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nerve serving muscle that produces movement of joint innervates joint and skin
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hilton's law
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area of skin innervated by the cutaneous branches of a single spinal nerve; all spinal nerves except c1 participate with some overlap
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dermatome
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-a rapid, predictable motor response to a stimulus
-many are unlearned and involuntary -many others are learned (aquired) reflex responses (driving, sports, etc.) |
reflex
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components of the reflex arc
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-receptor
-sensory neuron -integration center -motor neuron -effector |
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a reflex made up of one sensor neuron and one motor neuron
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monosynaptic reflex
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a reflex made up of at most three neurons
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plysynaptic reflex
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a reflex that affects the skeletal muscle
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somatic reflex
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a reflex that affects the viscera
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autonomic reflex
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resistance to stretch at rest
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tone
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the structures of spinal reflexes
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-muscle spindles
-golgi tendon organs |
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-ipsilateral withdarawl and contralateral enxtensor reflex
-occurs when you step on something painful -helps maintain balance |
crossed extensor reflex
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-elicited by gentle cutaneous stimulation
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superficial reflexes
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tests L4 to S2 and indirectly determines if corticospinal tracts are working; elicited by blunt object moved downward on lateral sole of foot and causes downward flexion of toes
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plantar reflex
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(when the great toe dorsiflexes and others fan) (in infants) if primary motor cortex or corticospinal tract is damaged; occurs in infants up to one year.
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babinskis sign
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stroking skin around umbilicus may induce contraction of abdominal muscles; checks the integrity of T8-T12
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abdominal reflexes
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division of the peripheral nervous system, efferent (motor) division, consisting of sympathetic and parasympathetic systems
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autonomic nervous system
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smooth and cardiac muscles and glands (viscera) skeletal muscles (somatic)
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effectors
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somatic motor neuron cell bodies in CNS and are ___.
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type A (large, myelinated) fibers
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found in the CNS preganglionic axon synapses with secondmotor neuron
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preganglionic neurons
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second in the chain; synapse is in autonomic ganglion outside the CNS; postganglionic axon to effector
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postganglionic neurons
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ANS is __ then CNS
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slower
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there are __ ganglia of the motor neurons in the somatic division
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NO
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all somatic neurons release __ on skeletal muscle fibers
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Ach
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postganglionic ANS fibers release __
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NE (sympathetic) and Ach (parasympathetic)
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NE and ACh may be __or __ depending on target tissue receptors
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excitatory or inhibitory
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division of the peripheral nervous system, efferent (motor) division, consisting of sympathetic and parasympathetic systems
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autonomic nervous system
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smooth and cardiac muscles and glands (viscera) skeletal muscles (somatic)
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effectors
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somatic motor neuron cell bodies in CNS and are ___.
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type A (large, myelinated) fibers
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found in the CNS preganglionic axon synapses with secondmotor neuron
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preganglionic neurons
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second in the chain; synapse is in autonomic ganglion outside the CNS; postganglionic axon to effector
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postganglionic neurons
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ANS is __ then CNS
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slower
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there are __ ganglia of the motor neurons in the somatic division
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NO
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all somatic neurons release __ on skeletal muscle fibers
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Ach
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postganglionic ANS fibers release __
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NE (sympathetic) and Ach (parasympathetic)
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NE and ACh may be __or __ depending on target tissue receptors
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excitatory or inhibitory
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many spinal and many cranial nerves contain both ___.
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somatic and autonomic nerves
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generally innervate same organs and have opposite effects on each (dual innervation)
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parasympathetic and sympathetic
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-resting and digestive system
-minimizes body energy uses and directs housekeeping activities (digestion, etc.) |
role of parasympathetic division
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fight or flight response, releases adrenaline
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sympathetic
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largest nerve vagus nerver
"resting" and digestion |
parasympathetic
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-fight or flight system
-increased heart rate and breathing rate and depth -visceral blood vessels constrict and vessels of heart and muscle dilate -bronchioles dilate (more O2) -liver releases glucose (more energy) -GI tract and urinary tract motility decrease |
sympathetic
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site of origin of parasympathetic and sympathetic differ
-lengths of pre-and postganglionic fibers -location of ganglia |
ANS
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-fibers from brain stem and sacral region
-preganglionic axons extend from CNS nearly to effector -terminal or intramural ganglia close to or in target organ |
parasympathetic (craniosacral) division
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makes pupils constrict, bulging of lenses, moves the eyes
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oculomotor nerves (III)
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control glandular secretions; lacrimal glands, submandibular and sublingual glands
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facial nerves (VII)
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control the parotid salivary glands behind ears, only preganglionic fibers; postganglionic fibers hitchhike with trigeminal nerves
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glossopharyngeal (IX)
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-90% of all preganglionic parasympathetic fibers
-fibers to serve virtually every organ |
vagus nerves (X)
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-S2-S4
-serves distal half of large intestine, urinary bladder, ureters and reproductive organs |
sacral outflow
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preganglionic sympathetic fibers leave ventral horn, pass through this and enter paravertebral chain ganglia that form part of teh sympathetic trunk (chain)
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white ramus communicans
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serve blood vessels of organs
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splanchnic nerves
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serve abdominopelvic viscera; generally inhibit abdominal organs
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abdominal aortic plexus
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secrete NE and E in blood (rush of adrenaline)
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pathways with adrenal medulla synapses
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detect chemical changes, stretch, irritation of organs; first link in autonomic reflex
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visceral sensory neurons
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same components as somatic, but two-neuron motor chain
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visceral reflex arcs
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visceral pain afferents travel along same pathways as somatic pain fibers; brain interprets pain as coming from more common somatic pathway
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referred pain
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all preganglionic fibers and all parasympathetic postgnaglionic axons secrete Ach
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Cholinergic fibers
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most sympathetic postganglionic axons release NE; exceptions are sweat glands and some vessels in skeletal muscles that secrete Ach
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adrenergic fibers
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motor end plates (somatic) and adrenal medulla Ach is always stimulatory
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nicotinic receptors
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all effector cells stimulated by cholinergic fibers (para and a few sympathetic); Ach is stimulatory or inhibitory
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muscarinic receptors
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adrenergic receptors
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-alpha
-beta |
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adrenergic receptor where NE is stimulatory
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alpha receptors
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adrenergic receptor wehre NE generally is inhibitory; eceptions include heart (stimulates)
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Beta receptors
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organs have predominately one type of adrenergric receptors because?
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they either stimulate or inhibit organs
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block or stimulate selected organs by nowing type of receptors
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drugs
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anticholinergic; blocks parasympathetic effects; (salivation, respiration, secretions, dilates pupils)
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atropine
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treatment of myathenia gravis; inhibits AChE
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neostigmine
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drugs like acebutolol, metoprolol. reduce heart rate and prevent arrythmias (taken by anxious people)
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beta-blockers
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binds to beta receptors adrenergic receptors to enhance vasodilaion
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albuterol
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most organs are innervated by both types of nerves
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dual innervation
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interactions of the heart, respiratory and GI tract
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antagonistic interactions
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continual partial contraction of most vessels due to sympathetic innervation; sympathetic controls blood pressure, even at rest
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sympathetic (vasomotor) tone
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dominates heart and smooth muscle of digestive and urinary tracts; most glands (except adenal and sweat) actibated by parasympathetic (sympathetic can override during stress)
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parasympathetic tone
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external genitalia; parasympathetic for erections and sympathetic for ejactulation
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cooperatibe effects
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arrecor pili, vesseldilation, sweat gland activation when hot and vice versa
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thermoregulatry responses to heat
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promotes release of renin from kidneys
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promotes increased blood pressure
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-increased metabolic rate of cells
-increased blood glucose level -mobilization of fats for fuel -increased mental awareness via RAS of brain stem -skeletal muscles contract more strongly and quickly |
metabolic effects via adrenal medullary hormones
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-one pre-to one or a few postganglionic neurons
-all release ACh which is quickly broken down short, localized effects |
parasympathetic
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pre- to many postganglionic neurons at several levels; longer-lasting due to:
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1. NE inactivated more slowly than ACh because it relies on reuptake
2. NE acts through second-messenger system (slower) 3. NE (15%) and E (85%) secreted by adrenal medulla; E is more potent and effects last longer then Ach until hormones by the liver |
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the reticular formation that exerts most direct effects (cardiovascular center, respiratory centers)
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brain stem and spinal cord
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integration center via relay through reticular formation that influences preganglionic ANS motor neurons in CNS, pysicological responses to emotions. main control over ANS
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hypothalamus
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conscious control of autonomic functions
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meitation
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-provide awareness of what is happening in our bodies
-data "fed back' to subject by signals (lights or tones) and subjects asked to try to alter or control by concentrating on pleasant thoughts -migraine headache, stress management |
biofeedback
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the eye contains _% of all sensor receptors of the body
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70
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only the anterior 1/6 of the __ is visible
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eye
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shade eyes, prevent perspiration from dripping into them
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eyebrows
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fleshy area containing sebaceous and sweat glands' produces oily secretion (sleep bugers)
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caruncle
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richly innervated with root hair plexuses to make it more sensative, helps protect the eye
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eyelashes
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modified sebaceous glands that produce lubricating oily secretion
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meibomian (tarsal) glands
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-delicate mucous membrane lining eyelids and surface of eye, respectively
-primary functions to produce lubricating mucous |
conjunctiba
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inflammation and infection of conjunctiva, respectively
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conjunctivitis and pinkeye
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produces tears
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lacrimal gland
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bactericidal enzyme in tears
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lysozyme
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white posterior portion
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sclera
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-clear for light to enter
-many pain fibers -only tissue in the body that can be directly transplanted without rejection because of lack of blood vessels |
cornea
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posterior 5/6 of uvea
-brown due to melanocytes because it absorbs light shined on it that gives us good color and precise vision during the day. |
choroid
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-continuous with choroids
-thick ring around lens -primary component is cilliary muscles that control the lens shape |
ciliary body
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connects to lens to stabalize
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suspensory ligament
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-visible colored portion between cornea and lens
-continuous with ciliary body -acts as a diaphragm to control pupil size |
iris
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how many pigments does the eye have?
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1. only brown pigment, but amount makes them range from brown to gray, pigment develops after birth
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opening in iris
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pupil
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pigmented epithelial cells in a single layer; absorb light, act as phagocytes, and store vitamin A needed for photoreceptors
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pimented layer of the iris
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transparent; millions of photoreceptors and other neurons; three types of cells here
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neural (nervous) layer of the retina
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cells nearest the pigmented layer in the neural layer of the retina
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photoreceptors
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no photoreceptors where optic nerve starts
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optic disc (blind spot)
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most numerous photoreceptors; sensitive to light but do not produce sharp or color images
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rods
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photorecpetors that need bright light; give high quality color vision
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cones
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yellow spot lateral to blind spot
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macula lutea
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at center of macula lutea; only cones for greatest acuity
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fovea centralis
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-fills posterior segment; clear gel with free collagenic fibrils
-lasts a lifetime -transmits light, supports posterior surface of lens and holds neural retina against pigmented layer -contributes to intracular pressure to counteract extrinsic eye muscles |
viterous humor
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-fills anterior segment, which is composed of anterior and posterior chambers that are divided by the iris
-similar to blood plasma; continually drains |
aqueous humor
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drainage of aqueous humor blocked and pressure increases; should have a yearly exam after age 40 to check for this
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glaucoma
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biconvex, transparent, flexible for focusing on retina
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lens
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fixes the lens in place
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suspensory ligment
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why is the lens avascular?
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for transparency
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usually clouding of lens due to hardening and thickening; diabete, smoking or sun exposure; can be replaced with an artificial lens
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cataract
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visible light has wavelength of __ (blue green red)
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400-700 nm
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we mostly see __ light
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reflected
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bending of light ray when it meets surface of a different medium at an angle
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refraction
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convex lens bends light rays so they converge at a __
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focal point
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__ responsible foremost of the refraction but has a constant thickness
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cornea
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__ accounts for fine focusing of objects <20 ft away
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lens
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distance beyond which no lens shape change needed; 20 feet for emmetropic eye (normal)
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far point of vision
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diverging light rays bent more sharply; ciliary muscles contract, suspensory ligament tension is released and elastic lens recoils and bulges
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accommodation of lenses
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reduce pupil size to prevent most divergent light rays from entering eye (otherwise would be blurry)
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constriction of pupils
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oculomotor nerve; directs eyes toward object
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convergence of eyeballs
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-when things are focused in front of retina
-eyeball is elongated -requires concave lenses to diverge light |
myopia (nearsightedness)
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parallel light rays (distance) focused behind retina
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hyperopia (farsightedness)
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have rod-shaped outer segement while cones have short conical one
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rods
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light absorbsing pigments in outer segments
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visual pigments
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light-absorbing molecule that combines with opsins (proteins) to form 4 types of visual pigments made from vitamin A (stored by liver)
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retinal
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type of opsin bound determines __
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wavelength of light absorbed
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retinal-opsin combination breaks down, allowing all trans retinal and opsin to seperated when rhodopsin absorbs light
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bleaching of the pigment
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essentially same as for rhodopsin but threshold for activation is much higher (only respond to high-intensity light); three types of cones sensitive to different wavelengths with some overlap each has a different opsin
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excitation of cones
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congenital lack of one or more cone types (sex linked)
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color blindness
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-when you move from darkness into bright light
-sensitivity of retina decreases and retinal neurons adapt rapidly, switching to cone system (takes 60 seconds and continues to improve for 5-10 min) |
light adaptation
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|
-happens when you move from a well lit area to a dark place
-cones stop functioning and rod pigments have been bleached out, so rods are still inhibited -rhodopsin eventually accumulates (20-30 min) |
dark adaptaion
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rod funciton hampered; usually a vitamin A deficiency that can lead to rod degeneration if vitamin A not restored
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night blindness
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our kind of vision; different view form each eye and crossing over of fibers
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stereoscopic vision
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animalls with eyes laterally, so visual fields overlap very little
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panoramic vision
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only possible with steroscopic ; 3D vision due to fusion of 2 slightly different images
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depth perception
|
|
auricle to tympanic membrane, lined with ceruminous glands
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external auditory canal (meatus)
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boundary between outer and middle ear; connective tissue that vibrates with sound waves
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tympanic membrane (eardrum)
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mucous lined cavity in temporal bone
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middle ear (tympanic cavity)
|
|
-links middle ear with nasopharynx
-normally closed, but swallowing or yawning opens it briefly to equalize pressure of middle ear with external (eardrum does not vibrate well otherwise) |
pharyngotmpanic tube (eustacian tube)
|
|
inflamation of middle ear; kids auditory tubes are shorter and more horizontal
|
otitis media (ear infection)
|
|
-smallest bones in body, make up the ear bones
-transmit vibrations to oval window, causing fluid movement in inner ear; articulations complete with tiny minisynovial joints -tensor tympani and stapedius are muscles that contract reflexively to prevent ear damage due to loud sounds; tympanic reflex reduces sound conduction but takes 40 ms, so sudden noises can still damage |
ossicles
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|
ossicle secured to the eardrum
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malleus (hammer)
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middle ossicle
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incus (anvil)
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ossicle that fits into oval window
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stapes (stirrup)
|
|
bony cavity; contains vestibule, cochlea and semicircular canals
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bony (osseous) part of the labyrinth
|
|
interconnecting membranous sacs and ducts in bony labyrinth
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membranous labyrinth
|
|
-central cavity of bony labyrinth
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vestibule
|
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membranous labyrinth sacs in vestibule perlilymph; house equilibrium receptors called maculae
|
utricle and saccule
|
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swelling at one end of each semicircular duct that houses the crista ampullaris (equillibrium receptor)
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ampulla
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membranous part of the cochlea
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cochlear duct
|
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receptor for hearing in chochlear duct
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spiral organ of corti
|
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"roof" of cochlear duct composed of spiral lamina and basilar membrane that supports organ of corti
|
vestibular membrane
|
|
must have elastic medium for tranmission; 2mps
|
sound
|
|
number of waves that pass a point in a given time; shorter wavelength, higher frequency; perceived as different pitches
|
frequency
|
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intensity (loudness) of sound (measured in decibles)
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amplitude
|
|
ossicles transmit and amplify __ to oval window
|
sound
|
|
oscillation of basal part of cochlear duct sends pressure waves through perilymph
|
basilar membrane
|
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on top of basilar membrane and composed of supporting cells and cochlear hair cells (one row of inner hair cells and 3 rows of outer hair cells)
|
organ of corti
|
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gell-like membrane over hair cells
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tectorial membrane
|
|
interference with vibrations; earwax, ruptured eardrum, otoscleosis of ossicles (hardeing of teh ear duct due to age)
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conduction deafness
|
|
damage to neural structures from cochlear hair cells to auditory coritical cells
|
sensorineural
|
|
ringing in the ears; symptom of chochlear nerve degeneration; inflammation of inner or middle ears, side effect of medications like asprin
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tinnitus
|
|
labyrinth disorder; vertigo, nausea, vomiting, balance problems
|
meniere's syndrome
|
|
relies on hearing and vision, stretch receptors of muscles and tendons
|
equillibrium
|
|
semicircular canals and vestibule receptors
|
vestibular apparatus
|
|
sensitive to linear acceleration (straight line changes in speed and direction) but not rotational movement
|
static equillibrium
|
|
-sensory receptors in each saccule and utricle
-monitor poition of head in space and therefore regulate posture |
maculae
|
|
jellylike mass that the hairs embedded in; has tiny stones or otoliths of calcium carbonate that increase weight of membrane and inertia
|
Otolithic membrane
|
|
major stimuli are angular movements (rotation)
|
crista ampullaris
|
|
sensitive to angular movements and rotation
|
dynamic equilibrium
|
|
gel-like mass with a pointed cap
|
cupula
|
|
you have approximately ____ tastebuds, mostly on the tongue
|
10000
|
|
tastbuds between and on top of the tongue
|
papillae
|
|
on entire surface with most on tip and sides of tongue; buds on top
|
fungiform papillae
|
|
larger, less numerous, back of tongue; taste buds on tops
|
circumvallate papillae
|
|
the receptor cells responsible for taste
|
gustatory cells
|
|
microvilli on tips of above cells that project through taste pore
|
gustatory hairs
|
|
stem cells that differentiate into supporting cells that in turn give rise to new gustatory cells
|
basal cells
|
|
you shed your tastebuds every
|
7-8 days
|
|
tastes:
|
-sweet
-salty -sour -bitter -umami (amino acid glutamate) |
|
taste is __% of smell
|
80
|
|
roof of nasal cavity
|
olfactory epithelium
|
|
bowling-pin shaped cells; surrounded by supporting cells with a yellow-brown pigment
|
olfactory receptor cells
|
|
cilia increase surface area; covered with mucus from supporting cells and olfactory glands
|
olfactory hairs
|
|
the only actual neurons that turnover throughout life (every 60 days)
|
olfactory nerves
|
|
in order to smell something it must be a __
|
water soluble gas
|
|
-lack of smell
-head injury (olfactory nerve damage) -physical obstruction; aging, inflamation, zinc defincency (growth factor for receptors) |
anosmia
|