Anatomy - Exam 4.txt

  1. Somatic motor system controls:
    -skeletal muscles
  2. ANS controls:
    -visceral muslces
  3. Peripheral Nervous Systemn consists of:
    -Peripheral nerves and Ganglion
  4. Afferent sensory system (PNS):
    -General and special senses coming into CNS
  5. Efferent sensory system (PNS):
    • -Somatic nervous system controlling SKELETAL muscles (Voluntary)
    • -Autonomic nervous system controlling smooth muscles, cardiac muscles, glands (Involuntary)
  6. The role of the Autonomic Nervous System:
    • 1.) Operates without conscious sontrol via reflex centers in spinal cord and brainstem controlled by hypothalamus
    • 2.) Regulated by higher brain centers that affect the hypothalamus
    • -Limbic system, thatlamus, cerebral cortev
    • 3.) Coordinates processess that maintain homeostasis (negative feedback)
    • -Cardiovascular, respiratory, digestive, urinary, reproductive, etc.
  7. Hypothalamus=_____
    • headquarters
    • -ANS responses and endocrine systems
  8. The ANS is divided into two divisions that jointly control most visceral responses:
    • 1.) Sympathetic division (Fight or flight)
    • -expenditure of energy
    • -Dominant under emotional stress
    • 2.) Parasympatheic division (rest and digest)
    • -Conserve and restore body energy, rest and recovery
    • -Dominant control during rest
  9. What is a maximum response?
    • Everything for a sympathetic response kicks in and activates fight or flight response that occurs simultaneous
    • ex. bear
  10. Sympathetic response includes:
    • -heart rate increases (above 100)
    • -respiratory rate increases
    • -pupils dilate (to be more aware of surroundings)
    • -digestion slows down
    • -heat production increases
    • -Blood vessels: to heart=dialte
    • *to skeletal muscles=dilate
    • *to GI tract=constrict
    • *to brain=dilate
    • *to kidneys=constrict
    • -respiratory muslces relax (relaxes trachea to get more air)
    • **full body response
  11. Parasympathetic response includes:
    • -heart rate decreases (below 100)
    • -respiratory rate decreases
    • -digestion increases
    • -Blood flow: to GI tract increases
    • *to kidneys increases
    • *to sexual organs increases
    • -respiratory muscles constrict
    • **Localized
  12. Dual innervation:
    When something is innervated by sympathetic and parasympathetic neurons
  13. Heart:
    • -Sympathetic increases heart rate
    • -Parasympathetic decreases heart rate
  14. Pupils:
    • -Sympathetic dilates pupils
    • -Parasympathetic constricts pupils
  15. Digestive Tract:
    • -Sympathetic decreases motility and secretions
    • -Parasympathetic increases motility and secretions
  16. Bronchioles:
    • -Sympathetic dilates airways
    • -Parasympathetic constricts airways
    • *bronchioles lead to alveoli in respiratory tract
  17. Norepinephrine gives a __________ response
  18. Effectors with sympathetic input only:
    • -sweat glands (increased secretions)
    • -arrector pili muscles
    • -blood vessels of skin, skeletal muscles, heart, lungs, brain (dilation)
    • -blood vessels of digestive viscera and kidney (constriction)
  19. Effectors with parasympathetic input only:
    -Lacrimal glands (increased secretion)
  20. ANS is straight forward - always sends ___ neurons out
  21. Structure of ANS: (Efferent pathway is 2 neuron pathway)
    • 1.) motor neurons in CNS send axons (preganglionic) to synapse on motor neuronsi n autonomic ganglia in PNS
    • 2.) motor neurons in sutonomic ganglia (ganglionic cells) send axons (postganglionic axons) to synapse on effector
  22. Structure of sympathetic:(Thoraco-lumbar division)
    • Preganglionic cell body in lateral horn of spinal cord segments (T1-L2)
    • Preganglionic axon typically shorter
    • Ganglion typically close to CNS
    • -sympathetic chain ganglia
    • -collateral ganglia
    • -adrenal medulla
  23. Structure of parasympathetic: (Cranio-sacral division)
    • -Preganglionic cell body in nuclei of CN III, VII, IX, X, and lateral horn of spinal cord segments S2, S3, S4
    • -Preganglionic axon typically longer
    • -Ganglion typically near or in effector organ, so postganglionic axon is shorter
  24. Organization and anatomy of the sympathetic division:
    • 1.) SC segments T1-L2- ventral roots contain preganglionic axons
    • 2.) White ramus branch from ventral root carries axons to sympathetic chain ganglia
    • 3.) Some axons synapse on cells of chain ganglia (closest to CNS--line up along SC)
    • 4.) Some axons pass through going to collateral ganglia and adrenal medulla
  25. Sympathetic division: Sympathetic chain ganglia (Thoraco-lumbar)
    • -2 chains of ganglia- one on each side of the vertebral column (Right and Left)
    • -Cervical chain ganglia are fused into superior, middle and inferior
    • -Innervate head, body wall, limbs, and viscera of thoracic cavity (heart, lungs)
    • **most synapse at collateral chain ganglia
  26. Sympathetic division: Collateral ganglia (Thoraco-lumbar)
    • -Located close to large abdominal arteries
    • -3 types of collateral ganglia and corresponds with abdominal organ: Celiac, superior mesenteric, inferior mesenteric ganglia
    • -Preganglionic fibers in anterior root, white ramus, then pass through chain ganglia and form splanchnic nerves to reach collateral ganglia
    • -Innervate abdominal and pelvic viscera (Sympathetic activation decreases blood flow and releases stored energy molecules)
  27. Sympathetic division: Adrenal medulla (Thoraco-lumbar/secretes epi and norepi)
    • -Central portion of the adrenal gland
    • -Preganglionic fibers in anterior root, white ramus, then pass through chain ganglia and splanchnic nerve to superior mesenteric ganglia, pass through to reach adrenal gland (before there's a synapse)
    • -Postganglionic cells in adrenal medulla are modified neurons that secrete into blood rather than onto effector
  28. Parasympathetic division: (Cranio-sacral)
    • 1. Preganglionic neurons in the brainstem and sacral segments of SC
    • 2. Ganglionic neurons in peripheral ganglia located near or within target organs
    • 3. Effects produced by the parasympathetic division include relaxation, food processing, energy absorption
  29. SC segments S2, S3, S4:
    • -Pelvic nerves carry preganglionic axons to parasympathetic intramural ganglia located in wall of viscera in inferior portion of abdominal pelvic cavity
    • -Short postganglionic axon innervate effectors (LONG pre-ganglionic)
  30. Cranial nerve III: (Oculomotor)
    -Parasympathetic control of pupil and lens
  31. Cranial nerve VII: (Facial)
    -lacrimal and salivary glands
  32. Cranial nerve IX: (Glossopharyngeal)
    -salivary glands
  33. Cranial nerve X: (Vagus nerve)
    • -Carries 75% of all parasympathetic output
    • -Parasympathetic control of heart, lungs, digestive tract and all other thoracic and abdominal viscera, except most inferior portions
    • **heart to intestines=vagus
  34. Can't survive with damage to your __________ nerve
  35. Autonomic Activation:
    -Sympathetic and parasympathetic divisions are activated by different stimuli
  36. Sympathetic innervation is ____________ body
  37. Each preganglionic axon branches to synapse onto ____ or more ganglionic cells (symapthetic)
  38. Adrenal medulla releases _____________ and norepinephrine into blood stream, affecting tissues not innervated by ANS
  39. Parasympathetic activation has __________ effect
  40. Parasympathetic activation innervation is limited to _______ and __________, doesn't innervate body wall, skin
    head, viscera
  41. Parasympathetic activation: each preganglionic axon branches to synapse onto only ___-____ ganglionic cells
  42. Parasympathetic activation: postganglionic axons generally fo to a ______ effector
  43. Synapse of preganglionic axon onto cell in autonomic ganglion: Neurotransmitter is ____ in both symp. and parasymp ganglia
    Ach (always)
  44. Synapse of postganglionic axon to effector:
    • -All parasympathetic postganglionic axons release Ach onto effectors
    • -Sympathetic postganglionic axons to dual innervated viscera release norepinephrine onto effectors
  45. Response always depends on ______
  46. Postsynaptic _________ properties determines effect of neuroransmitter on postsynaptic cell
  47. Many neurotransmitters have more than one type of ____ synaptic receptor
  48. Nicotinic cholinergic receptors:
    • -Skeletal muscles, autonomic ganglia
    • -ALWAYS excitatory (can be chemically gated)
    • **at every ganglion
  49. Muscarinic cholinergic receptors:
    • -excitatory OR inhibitory (depends on organ it's a receptor for)
    • -Visceral muscles, cardiac muscles, CNS
  50. Alpha Adrenergic receptors:
    • -Excitatory effect on smooth muscles of blood vessels of skin & viscera, causes constriction
    • **Alpha blockers-reduce hypertension
  51. Beta adrenergic receptors:
    • -Beta 1: excitatory on cardiac muscle
    • **Beta blockers reduce heart rate
    • -Beta 2: inhibitory on smooth muscles of respiratory tract, causes relaxation
  52. Synapse of preganglionic axon onto cell in autonomic ganglion:
    • -Neurotransmitter is ACh
    • -Postsynaptic receptor is ALWAYS nicotinic cholinergic (excitiatory)
    • -same in sympathetic and parasympathetic ganglia
  53. Synapse of postganglionic axon to effector:
    -different neurotransmitter and postsynaptic receptors depending on synapse
  54. Dually innervated = what hormone?
  55. Sympathetic postganglionic axons to:
    • -viscera that have dual innervation: release norepinephrine onto effectors (adrenergic synapses)
    • -viscera that receive ONLY sympathetic input: release NE or ACh or NO onto effectors (blood vessels to skin)
  56. Sympathetic postganglionic cells of the adrenal medulla:
    -release epinephrine and (some) NE into the blood stream (act as hormones)
  57. Sympathetic postganglionic NE axons end in branching network with multiple ___________ filled with neurotransmitters
  58. Removal of NE after release is slower because:
    • -Can't break down quickly like ACh
    • -Reuptake and reuse
    • -Breakdown by monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT) in surrounding tissue and in liver
  59. MAO breaks down _______
  60. Alpha adrenergic receptors:
    • -Excitatory effect on smooth muscles of blood vessels of skin and viscera, causes constriction
    • **alpha blockers reduce hypertension
  61. Beta adrenergic receptros:
    • -Beta 1: excitatory on cardiac muscles
    • **beta blockers reduce heart rate
    • -Beta 2: inhibitory on smooth muscles of repiratory tract, causes relaxation
  62. Why should people not take Beta 2 blockers?
    Cause airway to constrict
  63. Which receptors are stimulated more by NE?
  64. Epinephrine stimulates ________ alpha and beta receptors
  65. Localized sympathetic activity from NE release at ______
    • -variscosities
    • **primarily affects alpha receptors near the active variscosities
  66. Generalize sympathetic activity and release of _______ by adrenal medulla affect alpha AND beta receptors through out the body
  67. Operates without ___________ control via reflex centers in autonomic ganglia, spinal cord, and brainstem
  68. Reflex centers are controlled by the _________-
  69. What is autonomic tone?
    • Basis for homeostasis
    • -background level of activity
  70. Activation of sympathetic and/or parasympathetic input can increase or decrease ___________
  71. Visceral reflexes:
    • -Afferent input from sensory receptor/neuron
    • -Processing center with one or more interneurons
    • -Efferent pathway to effectors
  72. Reflex processing centers:
    • -Short reflexes (occur in autonomic ganglia - bypasses CNS)
    • -Long reflexes (occur in CNS - hypothalamus or other center in brainstem) **Consciously aware but not conscious control
  73. Short reflexes:
    • -Bypass the CNS entirely
    • -Involve sensory neurons and interneurons with cell bodies located in the autonomic ganglia, control ganglionic motor neurons
    • -Typically control very simple motor response with localized effects whereas long reflexes coordinate activity of an entire organ
    • **faster
  74. Short reflexes in Enteric system:
    • -Extensive networks of intramural ganglia and nerve networks in walls of digestive tract
    • -influenced by sympathetic and parasympathetic input but many complex visceral relexes are initiated and coordinated locally without instructions from CNS
    • *muscle contraction pushes everything through GI tract
    • **smell, taste, eating food sets off reflexes to digest it
  75. Long reflexes are the autonomic equivalent of ________ reflexes in somatic system
  76. Long reflexes sensory input:
    • -Visceral sensory neurons such as chemoreceptros, baroreceptors, etc. (Anything that detects change in chemicals in body - chemoreceptros)
    • -General senses such as pain, touch, temperature, etc.
    • -Special senses (smell, taste, vision, etc.)
  77. Long reflexes processing steps involve ______ with in CNS
  78. Simple reflexes in SC provide relatively _____ and stereotypic responses to stimuli
  79. Processing centers in the medulla and pons provide more __________ sympathetic and parasympathetic reflexes
  80. Autonomic Parasympathetic reflexes:
    Typically affect individual organs/systems reflecting the relatively __________, restircted pattern of parasympathetic innervation
  81. Parasympathetic reflexes include:
    • -Defecation reflex
    • -Urination reflex
    • -Direct light and consensual light reflex
    • -Swallowing reflex
    • -Coughing reflex
    • -Baroreceptor blood pressure reflex
    • -Sexual arousal
  82. Some Sympathetic autonomic reflexes affect individual organs such as:
    • -Cardioacceleratory reflex
    • -Vasomotor reflex
    • -Pupil dilation reflex
    • -Ejaculation of semen (can't occure without sympathetic stimulation)
  83. Sympathetic division typically activated as a _______
  84. Release of NE and E as hormones produces widespread long lasting ________ effects
  85. Biofeedback:
    -link between limbic and autonomic system
  86. The hypothalamus:
    • -Controls autonomic function
    • -regulates body temp (thermostat)
    • -coordinates circadian cycles of activity
    • -produces emotions and behavorial drives
    • -coordination of voluntary, emotional, and autonomic functions
    • -coordinates activities of the endocrine and nervous systems
    • -secretes regulatory hormones
  87. Autonomic NS conrol and endocrine system controlled by:
  88. Sensory information comes into ____ from the sensory receptors via peripheral nerves
  89. Afferent sensory pathways synapse onto sensory processing interneurons in _____ horn of SC or cranial nerve nuclei in brainstem
  90. Only small percentage of sensory input reaches _______ awareness
  91. Afferent sensory response occurs only if ______ exist that are sensitive to stimuli
  92. Sensory receptros are specialized cell or ____ _______ that respond to specific stimuli, which are:
    • cell responses,
    • -dendrite of sensory neuron
    • -specialized cell that synapses onto dendrite of sensory neuron
  93. Receptor specificity:
    -each receptor respond only to certain types of stimuli
  94. Receptive field:
    -area monitored by a singel sensory receptor
  95. The longer the receptive field, the _____ precise the localization of the stimulus
  96. Sensory receptors translate ______ into bioelectrical activity of the nervous system
  97. Sensory receptors transduction:
    • -Stimulus changes membrane ion permeability producing the receptor potential (graded potential)
    • -Receptor potential controls depolarization at AP initiation site in sensory neuron dendrite
    • -AP frequency provides the CNS information on stimulus intensity
  98. Sensation:
    -information arriving from a stimulus
  99. Perception:
    -Conscious awareness of a sensation
  100. Labeled line:
    • -identifies type (modality) of stimulus and body location of receptor.
    • **pathway dermatomes take from spinal cord
  101. Sensory coding:
    -Pattern of AP's arriving convey information on strength (frequency), duration, and variation of the stimulus
  102. Adaptation:
    -Reduction in sensitivity in the presense of a constant stimulus due to changes in receptor response or central processing
  103. Tonic receptors:
    -Always active - rate of AP changes with changes in level of stimulation
  104. Phasic receptors:
    • -Produce AP only in response to changes in level of stimulation
    • -Fast-adapting receptors
  105. Peripheral Adaptation:
    • -Reduces amount of information that reaches the CNS
    • **phasic receptors, body adapts to temp changes
  106. Central adaptation:
    • -Inhibition along a sensory pathway
    • -Resrtricts amount of information that reaches the cortex and conscious awareness
    • **adapting to strange smells unless it's normal
  107. Reticular Activating system:
    • -Reduces or increases awareness of arriving sensations
    • **keep you alert or awake
  108. Gereral pain receptor:
    • nociceptors
    • -Present in all spinal nerves
    • -Present in CN V and CN X
    • **generally free nerve endings
  109. General temperature receptors:
    • thermoreceptors
    • -Present in all spinal nerves
    • -Present in CN V and CN X
  110. General senses for physical distortion:
    • mechanoreceptors
    • -Present in all spinal nerves
    • -Present in CN V and CN X
    • **pressure, stretching
  111. General senses for chemical detection:
    • -chemoreceptors
    • -Present in all spinal nerves
    • -Present in CN V and CN X
  112. Nociceptors:
    • -Free nerve endings: sensory neuron dendrites sensitive to various stimuli
    • *extremes of temperature (where it causes pain)
    • *mechanical damage (where it causes pain)
    • *chemicals released by damaged cells (converted to prostaglandins)
    • -abundant in suprficial skin, joint capsules, bone periosteum, blood vessel walls
    • -few in deep tissues and visceral organs
    • -Large receptive fields --> poor localization
  113. Fast pain: "prickling pain"
    • -carried by myelinated type A fibers (need immediate response)
    • -trigger somatic muscle reflexes
    • -relayed to cortex for conscious awareness
    • -can be localized to within a few inches
  114. Slow pain: burning, aching pain
    • -carried by unmyelinated type C fibers
    • -can be localized only to large body area
  115. Nociceptors are _____ receptors
  116. Central adaptation via inhibition in pain processing pathways:
    • -excitatory neurotransmitters of pain pathway: Glutamate and Substance P
    • -Inhibitory neurotransmitters: Endorphins and other "natural opiates" (make you realize you're not hurt until later)
  117. Anesthetics block _______ sensations
  118. What do local anesthetics do?
    -They block AP propagation
  119. What do general anesthetics do?
    -They suppress consciousness
  120. Analgesics (over the counter meds) _______ pain stimulus
  121. OTC meds (analgesics) inhibit ____________ synthesis, by blocking COX enzymes
  122. What blocks the COX enzyme?
    OTC or analgesics
  123. Non-steroidal anti-inflammatory drugs (NSAID's) block __________ and ____________
    COX 1, and COX 2 enzymes
  124. COX 2 inhibitors are _______ inhibitors
  125. ____________ are analgesics that reduce transmission of information about pain in CNS
    Opiates - agonists of endorphins
  126. ___________ are important to the transmission of pain
  127. _____________ are free nerve endings sensitive to change in temperature
  128. Thermoreceptors have more ________ sensitive receptors than warm sensitive receptors
  129. Where are thermoreceptors abundant?
    • -dermis
    • -skeletal muscle
    • -liver
    • -hypothalamus
  130. Thermoreceptors have ____________ receptive fields
    • large
    • -less specific than pain
  131. Thermoreceptors are _______ adapting receptors, or considered phasic
    • rapidly
    • -fast rate of acclimation to a temp that isn't painful
  132. Warm receptors:
    • -sensitive to temps above 77F
    • -unresponsive to temps above 113F
  133. Cold receptors:
    -sensitive to temp between 50F and 68F
  134. Pain receptors:
    • -respond to temp below 10C
    • -respond to temp above 45C
  135. What temp are we most comfortable at?
    between 70-77F
  136. What are chemoreceptors sensitive to?
    • -pH, CO2, and O2 levels of body fluids
    • **including CSF (goes to brainstem and respiratory centers) and Arterial blood (goes to carotid and aortic bodies)
  137. Chemoreceptors are _______ adapting receptors
  138. Chemoreceptors can ______ to new levels of O2 and CO2 after a duration of time
  139. Chemoreceptors have a ________ control of respiration and cardiovascular system
  140. Chemoreceptors have no pathways to ________ for conscious awareness
    • cortex
    • **O deficient people aren't always aware it's low
  141. Mechanoreceptors are sensitive to _______ of the cell membrane of the dendrites (or pressure)
  142. ____________ gated ion channels open in response to stretching, compression, etc.
  143. Baroreceptors:
    -Pressure in blood vessels and hollow organs
  144. Proprioceptors:
    • -Position of joints muscles
    • **in skeletal muscles and joints. Keep you upright. Abnormal stretching initiates reflex
  145. Tactile receptors:
    -touch, pressure, vibration
  146. Sensory coding:
    -pattern of AP's arriving convey info on strength, duration, and variation of the stimulus
  147. Labeled line:
    • -identifies type (motality) of stimulus and the body location of receptor (direct line from sensory cortex)
    • **projects to brain processing centers that are organize somatotopically
    • **most sensory info crosses over to contralateral areas of brain
  148. More intense stimulus=more _________
  149. Somatotopically organized=_________ representation of body regions
  150. Amount of space in cortex and pathways devoted to a particular body region is proportional to the number of _____ ________ it contains, NOT to the body region's absolute size.
    sensory receptor
  151. What are unipolar neurons primary role?
  152. Chemoreceptors have _______________ and receptor areas that have ______ gated ion channels
    exteroceptors, chemically
  153. Exteroceptors:
    -respond to chemical stimuli from external environment
  154. Olfaction and gustation receptors __________ rapidly and are continuously replaced with new cells
  155. Olfaction= sense of _______
  156. Olfactory epithelium is located in superior portion of _______ cavity, and is composed of:
    • -nasal
    • *olfactory receptors
    • *a lot of basal stem cells (constantly replaced)
    • *supporting cells, glands, blood vessels, etc.
  157. Olfactory epithelium surface is coated with mucus secretions from ______ glands, and what's the purpose of the mucus?
    • -olfactory
    • *to be detectable as a smell, chemical must be volatile (dissolved to gas form) and soluble in mucus
    • *mucus cleans olfactory epithelium, removing chemicals
  158. Olfactory receptors (cilia) are the ________ of bipolar neurons
  159. Cilia is a large area of membrane on which _________ gated channels are located
  160. Humans have approximately 50 different types of __________ neurons
  161. Each neuron type is sensitive to only _____ chemical
  162. Olfactory discrimination:
    • -Humans can detect, discriminate between, approx. 2000-4000 different chemicals
    • -CNS interprets between different SMELLS on the basis of the overall pattern of activity in the 50 different neuron types.
    • ***one smell can activate multiple pathways/neurons
  163. Olfactory receptors are very _____
    • sensitive
    • -Only a few molecules needed to open enough gates to reach AP threshold in some olfactory neurons
  164. Which is more sensitive, gustation or olfaction?
    olfaction (smell)
  165. Olfactory 1st Order Neuron:
    • -Receptor cell in olfactory epithelium:axon extend into CNS as cranial nerve I
    • **Approximately 20 small bundles of axons (nerves) go through the cribriform plate--instead of one singel peripheral nerve
  166. Olfactory: 2nd Order Neuron:
    • -located in olfactory bulb
    • **Much processing, including central adaptation (adjusting to a scent)
    • **2nd order axons from olfactory tract that diverges to multiple sites
  167. Olfactory: 3rd Order Neuron:
    • -at various locations (a lot of splitting of the 3rd order neuron)
    • **Olfactory cortex-medial surface of temporal lobe
    • **Hypothalamus
    • **Limbic system
  168. Gustatory discrimination:
    • -Humans can detect 4 to 6 "primary tastes"
    • -CNS interprets different tastes on the basis of the overall pattern of activity in the 4 to 6 different recetor types
  169. What are the 6 "primary tastes"
    -sweet, salty, sour, umami, water, bitter
  170. To be detectable as a taste, _______ must be dissolved
  171. Mulitple gustatory receptors can be activated, but they are ______ sensitive than olfactory receptors
  172. Taste buds:
    • -Contain gustatory receptor cells and basal stem cells (constantly replacing receptor cells)
    • -Recessed into surface of surrounding epithelium of lingual papillae
  173. Gustatory receptor cells:
    -4 to 6 different types of gustatory receptor cells, each sensitive to only one TYPE of chemical
  174. Most taste buds have ____ 4-6 types of receptor cells
    -all, can activated different combinations
  175. What 2 senses are gustatory receptors less sensitive too?
    sweet and salty
  176. What are gustatory senses most sensitive to?
  177. Gustatory receptors are 1000 times more sensitive to _____ than sweet and salty
    • sour (acids)
    • -because more dangerous
  178. Receptor cell in taste buds: ______ gated ion channels open, producing receptor potential
  179. Gustatory: 1st Order Neuron
    • -Dendrites receive synapse from receptor cell
    • -Amount of neurotransmitter released by receptor cell determines AP frequency in 1st order neuron
    • -Axon extends into CNS in cranial nerves
  180. Which cranial nerves affect tongue:
    • -CN VII (Facial): anterior 2/3 of tongue
    • -CN IX (Glossopharyngeal): posterior 1/3
  181. Level of stimulation of olfactory receptors has major role in ____ perception
  182. Aging reduces olfactory and gustatory sensitivity, because:
    • -Number of receptors decline with age as fewer new cells are produced (becomes dull)
    • -Receptor sensitivity declines
  183. Bony labyrinth of inner ear:
    • -surrounds and protects membranous labyrinth
    • -Contains PERILYMPH (outermost fluid)
  184. Membranous labyrinth of inner ear:
    -Contains ENDOLYMPH (inside fluid)
  185. What are the three areas the inner ear labyrinths are divided into:
    • -Vestibule, with utricle and saccule (middle)
    • -Semicircular canals, with semicircular ducts
    • -Cochlea, with cochlear ducts
  186. Hair cell=______ cell
  187. Specialized cells termed hair cells are ______ receptors
  188. Hair cells respond to ______ distortion of their cilia
  189. Amount of neurotransmitter released by hair cells controls AP frequency in _____ order neurons
  190. The sensory organs for hearing and equilibrium are located in the ____ _____
    inner ear
  191. Cranial nerve VIII (Vestibulocochlear): contains _____ order neurons that conduct AP's into CNS
  192. Semicircular ducts are responsible for ________ _______
    rotational movements
  193. Semicircular ducts: (location)
    -in cristae: small patch of hair cells in ampullary region at one end of each of the 3 ducts
  194. Utricle and Saccule:(location)
    -In maculae: small patch of hair cells-one inside utricle, one inside saccule
  195. Cochlear duct is responsible for _____
  196. Cochlear duct: (location)
    -In ORgan of Corti on Basilar membrane-long strip of hair cells extending the length of the coiled duct
  197. Cupula:
    -floating gelatinous mass in w hich "hairs" are embedded
  198. Semicircular ducts are only activated during ______
  199. Utricle and sacculae are ________ active
  200. Otolith:
    -"hairs" embedded in gelatinous mass containing calcium carbonate crystal (part of utricle and sacculae)
  201. Hair cells synapse onto 1st order sensory neurons, which enter CNS as _________ branch of CN VIII
  202. _____ order neuron located in vestibular nuclei of the brainstem
  203. 2nd order neurons in the vestibular neural pathway of the inner ear are responsible for:
    • -integrating input from left and right inner ears
    • -send info to the somato-sensory ears
    • -send info to the cerebellum (for coordination)
    • -send info to motor nuclei in BS and SC for reflex control of eye, head, and neck
  204. Motion sickness:
    • -sensory info from eyes and vestibules don't match up (a disconnect)
    • -can have adaptations to sensory info or hypersensitivity - depends on how well you handle the disconnect
  205. Nystagmus:
    -Condition when eyes jerk when following a light: indicates brainstem damage
  206. External and middle ear assist in getting stimulus (sound waves) to receptors in the _____ of the inner ear
  207. External ear (pinna and EAM) collects and ____ sound waves toward middle ear
  208. Middle ear (tympanic membrane and auditory ossicles) ______ and amplifies vibrations from tympanic membrane to onner ear
  209. What is the cochlea filled with?
    -perilymph and endolymph
  210. Sound waves enter at the _____ window
  211. Sound waves exit at the ______ window
  212. What is the pathway of sound waves:
    • 1. sound waves arriving at tympanic membrane cause it to vibrate (causing aussicles to move)
    • 2. Auditory ossicles conduct and amplify the vibration onto the oval window of the inner ear
    • -Tensor tympani and stapedius MUSCLES contract to reduce the amount of movement when lound sound arrives (hol din place to keep from causing damage to the oval window)
    • 3. In/out movement at the oval window creates pressure wave in the PERILYMPH of the cochlea
    • 4. Pressure waves vibrate the basilar membrane area of the cochlear duct
    • 5. Hair cells of the Organ of Corti are pushed against the tectorial membrane
  213. Sound frequency depends on where _____ will cross the membrane
  214. Basilar membrane _______ varies along length of cochlear duct
  215. Highest frequency sounds vibrate areas _______ to oval window on Basilar membrane
  216. Lowest frequency sounds vibrate areas ________ from oval window on Basilar membrane
  217. Higher intensity (louder) sounds cause larger ________ and stimulate more hair cells (intensity is measured in decibles)
  218. Hair cells synapse onto ____ order sensory neurons, which enter CNS as cochlear branch of CN VIII
  219. _____ order neurons located in cochlear nuclei of the brainstem
  220. 2nd order neurons decussate and ascend to _____ order neurons in inferior colliculi of mesencephalon
  221. Inferior colliculi coordinates ______ movement of head and neck to sounds
  222. 3rd order axons ascend to the _______, where there is conscious awareness and interpretation of sound
  223. Primary auditory cortex: (location)
    superior surface of the temporal lobe
  224. Auditory association cortex: (location)
    • in surrounding areas of temporal lobe
    • -left hemisphere interprets language
  225. Which special sense is the most complicated?
  226. Eye:
    -Sensory organ that collects and focuses light onto the photoreceptors (cones and rods)
  227. Cornea and lens focus light rays onto ______, located on the inner surface of eye ball
  228. Light passes through layers of retinal neurons to reach ____________
  229. The outer pigmented portion of the retina does what?
    • -Absorbs excess light
    • -Transports nutrients to neural part
  230. The inner neural part of the retina does what?
    • -Has photoreceptors: rods and cones
    • -1st order neurons: bipolar cells, axons
    • -2nd order neurons: ganglion cells, axons form the optic nerve and tract
    • -Embryologic origin:outgrowth from brain
  231. Eyes are a direct _____ of the brain
    outgrowth (meaning they are attached)
  232. Cones of the retina:
    • -provide color vision
    • -require more light to be activated than rods
    • -located in macula lutea portion of retina
    • -In highest concentration in FOVEA portion of macula
  233. Rods of the retina:
    • -Highly sensitive to light, allow fro vision in DIM light conditions
    • -found in retinal areas peripheral to macula
  234. You switch from color (cones) to black and white (rods) at _____
  235. Rods and cones convert _____ signals into electrical signals
  236. Current flowing through gated ion channels changes membrane potential, controls ______ of neurotransmitter released onto 1st order neurons
  237. Gated ion channels in the eye open when its _____
  238. Light causes _____ channels to close so cell hyperpolarizes, which allows us to see images
  239. Gated ion channels (mechanoreceptors and chemoreceptors) are indirectly controlled by _________
  240. Each photopigment has _______ molecule, which changes shape
  241. Light absorption activates enzyme pathway that controls ______ messenger (cGMP) levels that open gated channels
  242. Light is absorbed by retinal molecule embedded in an _______ protein molecule (cones)
  243. Retinal is synthesized from ________
    Vitamin A
  244. Opsins differ in which light frequencies can reach the ______ molecule
  245. Vitamin A and ______ are constantly recycled in the eye, which is why it takes months to have signs of a deficiency
  246. Rhodopsin=______
  247. Rods respond to a ______ range of light wavelengths
    • wide
    • -responds to all the different wavelengths of the different colors
  248. What are the 3 opsins?
    Red, blue, and green sensitive cones
  249. Cones respond to specific, _______ ranges of wavelengths, ranges overlap
  250. The color white is perceived when all cones are _______ stimulated
  251. The color yellow is perceived when ______ cones are stimulated strongly, ________ cones are stimulated moderately, and ______ cones are not stimulated
    green, red, blue
  252. Colorblindness:
    • -the inablity to detect certain colors due to lack of one or more color opsins
    • -Inherited genetic trait: genes for red and green opsins are located on X chromosome
    • -there are varying degrees of blindness, depends on colors
  253. About ______ percent of cones are red cones
  254. Labeled lines of visual pathway:
    • -Each ganglion vell receives input from a specific receptive field of the retina, a group or photoreceptors
    • -Image of retina surface is mapped onto visual cortex
    • -Receptive fields are VERY SMALL IN FOVEA AREA OF RETINA (making it the SHARPEST vision)
    • *highest visual acuity
    • *large area on visual cortex
  255. Steps of the visual pathway:
    • 1. Light into eye
    • 2. Light to photoreceptors (cones and rods)
    • 3. Photoreceptors to bipolar cells to ganglion cells
    • 4. Axons of ganglion cells form the optic nerve and optic tract
    • **synapse on superior colliculus for visual reflex pathways
    • **synapse on 3rd order neurons in the thalamus for conscious processing pathway
  256. Primary visual cortex and visual association are in the ______ lobe of the brain
  257. Riht visual field projects to ______ visual cortex
  258. Left half of BOTH retinas view ______ visual field
Card Set
Anatomy - Exam 4.txt
Special and general senses