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319 Cards in this Set
- Front
- Back
How many parts to somatic sensory system?
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2
|
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What are the parts to the somatic sensory system?
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-Touch
-Pain and Temperature |
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Receptors for touch somatic sensory system?
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Mechanoreceptors
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Mechanoreceptors receptors?
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Skin
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Mechanoreceptors cell bodies?
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Dorsal Root Ganglion
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Mechanoreceptors primary afferent axons?
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Skin -> spinal nerves -> spinal cord
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Where do mechanoreceptors ascend?
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Ipsilateral side of the dorsal columns in the white matter
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What does afferent mean?
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Carries information into CNS
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What does efferent mean?
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Carries information out of the CNS
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Primary afferent axons for mechanoreceptors?
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A-beta
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What are the italian mechanoreceptors of the skin?
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Pacinian Corpuscle and Ruffini's Endings
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What are the german mechanoreceptors of the skin?
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Meissner's Corpuscle and Merkel's Disk
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Size of Pacinian Corpuscle receptor?
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largest
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Percentage of hand is Pacinian Corpuscle?
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10-15%
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Spacial acuity of Pacinian Corpuscle?
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Low 10+nm
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Point of Pacinian Corpuscle?
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Detected transmitted vibrations (tool use)
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Size of Ruffini's Endings?
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Second largest
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Percentage of hand is Ruffini's Endings?
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20%
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Spacial acuity of Ruffini's Endings?
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Low spacial acuity (7mm)
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Point of Ruffini's Endings?
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Gives information on hand and finger position
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Pacinian Corpuscle is sensitive to what?
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High frequency vibration
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Ruffini's Endings are sensitive to what?
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skin stretch from finger movement
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Size of Meissner's Corpuscle?
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1/10th the size of Pacinian Corpuscle
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Percentage of Meissner's Corpuscle on the hand?
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40%
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Meissner's Corpuscle is sensitive to what?
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Low vibrations such as texture on the skin
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Spacial acuity of Meissner's Corpuscle?
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Intermediate. 3 mm
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Point of Meissner's Corpuscle?
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Detect motion and grip control
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Size of Merkel's Disk?
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Smallest receptor
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Percentage of Merkel's Disk on hand?
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25% (predominantly on finger tips)
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Merkel's Disk is sensitive to what?
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Edges, points and curvatures
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Spacial acuity of Merkel's Disk?
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High. (.5 mm)
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Point of Merkel's Disk?
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Detect form and texture
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What is a receptive field?
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Area of skin that changes AP fire rate when stimulated
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What is a rapid adaptation receptive field?
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Detects change, but stops firing AP once change has become constant
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What is a slow adaptation receptive field?
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Detects change and keeps firing in response to change even if change has become constant
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What is a small receptive field size and rapid adapting mechanoreceptor?
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Meissner's Corpuscle
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What is a large receptive field size and rapid adapting mechanoreceptor?
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Pacinian Corpuscle
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What is a small receptive field size and slow adapting mechanoreceptor?
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Merkel's Disk
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What is a large receptive field size and slow adapting mechanoreceptor?
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Ruffini's Ending
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What does a corpuscle do for a mechanoreceptor?
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Makes it sensitive to high frequency vibration, but not to constant pressure
|
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8 Spinal segments?
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Cervical
|
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12 spinal segments?
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Thoracic
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5 spinal segments?
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Lumbar and Sacral
|
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What is a dermatome?
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Skin innervated on the right and left dorsal roots for a single spinal segment?
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Why do you need to cut 3 adjacent dorsal roots to remove feeling to dermatome?
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Because adjacent dorsal roots can overlap
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What is the Dorsal column-medial lemniscal pathway?
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Body receptors to the cortex
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What are the first order neurons for Body receptors to cortex?
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A-beta axons
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Where do A-beta axons enter?
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Through dorsal roots
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How and where do the A-beta axons get to the brain?
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They ascend through the ipsilateral dorsal column
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What is the topographic division for dorsal columns in body receptors to cortex? (They are tracts)
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Lower Body: Gracile Tract
Upper Body: Cuneate Tract |
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Where do the axons synapse onto the second order neurons in body receptors to cortex pathway?
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At the Second Order Neurons in the dorsal column nuclei
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Where do the lower body axons synapse?
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Gracile Nucleus
|
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Where do the upper body axons synapse?
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Cuneate Nucleus
|
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The part of the Second Order Neurons that cross over in the body receptors to cortex pathway is called what?
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Internal Arcuate Fibers
|
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What guides second order axons up the dorsal column in BR to Cortex?
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Medial Lemniscus
|
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What part of the brain does the medial lemniscus guide the second order neurons through for BR-Cortex pathway?
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Medulla, Pons and midbrain
|
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Where do 2nd Order Neurons synapse onto in BR-C pathway?
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Ventral Posterior (VP) Nucleus of the Thalamus
|
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What do the 3rd Order Neurons do?
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Project to the Primary Somatosensory Cortex (S1)
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Cell bodies for mechanoreceptors of the face?
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Trigeminal ganglion
|
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Primary Afferent Axons for BR of Face?
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Skin to Trigeminal nerve to ganglion
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How do BR face mechanoreceptors enter the Pons?
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Through Trigeminal Nerve
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Another name for trigeminal nerve?
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Cranial Nerve V
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Where are first order cell bodies in BRf-C?
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Trigeminal Ganglion
|
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Where does the second order synapse occur in BRf-C?
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On the ipsilateral trigeminal nucleus
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What is the structure called when Second order neurons crossover in BRf-C?
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Trigeminal lemniscus
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What side of dorsal column does lemniscus ascend in BRf-C? And to where?
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the contralateral. The thalamus
|
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Where do second order axons synapse in BRf-C?
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Ventral Posterior Medial (VPM) Nucleus of the Thalamus
|
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Where do VPM Neurons project to? And what order are these neurons?
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Project to primary somatosensory cortex (S1). Third order
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What is the primary somatosensory cortex called in Brodmann's terms?
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S1 = 3b
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What is the postcentral gyrus?
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3a, 1, 2
|
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What are posterior parietal cortex made of?
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5 and 7
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Where is texture felt?
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3b->1
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Where is size and shape perceived?
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3b-2
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How many layers does a human cortex have?
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3-6
|
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What is special about the human cortex and its organization?
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Alternates between rapidly and slowly adapting
|
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Which layer to thalamic inputs synapse on the S1?
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Layer IV.
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What is somatotropy?
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Sensations of the body mapped onto brain
|
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What does somatotropy show us?
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Cortex devotes more space to body parts of more importance
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What is pain?
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Perception of unpleasant things
|
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Does pain require activation of nociceptors?
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No
|
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Is pain subjective? And How?
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Yes. Each person has a different amount of pain they can take
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What is nociception?
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Activation of nociceptors and related neural pathways
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Does activation of nociception lead to perception of pain?
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Not necessarily
|
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What is part of the somatosensory system for pain?
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Nociceptors
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Nociceptors of the skin?
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Free Nerve Endings of A-Gamma and unmyelinated C Fibers
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What is the relation between nociceptors and thermoceptors?
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They are not the same
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How are nociceptors and thermoceptors different in response to stimulus (2 parts)?
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Thermoceptors do not increase fire rate as stimulus increases. Nociceptors only start firing when stimulus becomes noxious
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Unique aspect of free nerve endings?
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Polymodal. (multiple stimuli)
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Type of stimuli for nociceptors (3 of them)?
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Mechanical: Strong Pressure
Thermal: Burning Heat (>42 C) and Extreme Cold (<17 C) Chemical: histamine, protons |
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What is characteristic of A-gamma C Axons?
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Smallest diameter, lowest conductance
|
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What does A-Gamma axons typically sense?
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Pain, temperature
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What does C-axons typically sense?
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Temperature, pain, itch
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What causes the activation of nociceptors?
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When tissue breaks, chemicals are released that activate nociceptors
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What are substances that activate nociceptors?
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Bradykinin, ATP, and Potassium
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How does Bradykinin activate nociceptor?
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Depolarization through G-protein coupled reactions
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How does ATP activate nociceptors?
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Activates P2X receptors
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How does Potassim activate nociceptors?
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Depolarizes them
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What is Hyperglasia?
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Increased sensitivity at injury, injury site and surrounding area in pain
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What is sensitization?
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Increased activity and sensitivity in nociceptors b/c of tissue damage
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How are nociceptors sensitivized?
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Tissue damage releases chemicals
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Chemicals that are part of sensitivation of nocicpetors?
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Bradykinin, Prostaglandins, Substance P
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How does Bradykinin increase sensitivity in nociceptors?
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Increase sensitivity in ion channels like TRPV1
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How is Prostaglandins made? What can inhibit these?
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By enzyme released from damaged cells called cyclooxygenase. Aspirin and other NSAIDs
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How does Substance P increases sensitivity in nociceptors?
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Swelling of capilaries (vasodilation), releases histamine (activates mast cells)
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What is responsible for first pain?
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A-Gamma Axons
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What is responsible for second pain?
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C-axons
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Receptors for the nociceptors of the body?
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skin
|
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Cell bodies for nociceptors?
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dorsal root ganglion
|
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Primary afferent axons for nociceptors?
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skin -> spinal nerves (dorsal root) ->spinal cord
|
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How is information sent up and down spinal segments in nociceptor pathway?
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Lissauer's Tract
|
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Where is 2nd Order Neuron for nociceptors?
|
Substantia Gelatinosa
|
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Where is Substantia Gelatinosa located in spinal cord?
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Dorsal horn
|
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First order neurons in Spinothalamic pathway?
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A-Gamma and C-axons
|
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Where do neurons cross-over in spinothalamic pathway?
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Right after 2nd Order Neuron synapse
|
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Where does 3rd Order Neuron synapse at in spinothalamic pathway?
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Ventral Posterior Lateral (VPL) Nucelus of the thalaum and intralaminar nuclei
|
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Where does 3rd order Neurons project?
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Primary somatosensory cortex (S1)
|
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What is the structure that brings the 2nd order neurons to the third order neurons in the spinothalamic pathway called?
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Spinothalamic tract
|
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Primary Axons in Trigeminal Nociceptors?
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A-gamma and C-axons
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Where are the cell bodies found for Noc.Trig pathway primary neurons?
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Trigeminal Ganglion
|
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Where does the primary neurons travel first in the Noc.Trig pathway?
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Down first. From Pons to Caudal Medulla
|
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How does the primary neurons travel first in the Noc.Trig pathway?
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By Spinal trigeminal Tract
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Where is the synapse for Noc.Trig. pathway 2nd Order Neurons?
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In the Spinal Trigeminal Nucleus of the Caudal medulla
|
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What is structure called that is involved with the 2nd order neurons cross over in Noc.Tri. Pathway?
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Trigeminothalamic Tract or Trigeminal Lemniscus
|
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Where is 3rd Order Neurons in Noc.Tri. Pathway?
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Ventral Posterior Medial (VPM) nucleus of Thalamus
|
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Where do 3rd Order Neurons project to?
|
Primary somatosensory cortex (S1)
|
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What can influence activity of the PAG?
|
Emotional State
|
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Where is PAG located?
|
Midbrain
|
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What does PAG stand for?
|
Periacqueductal Gray
|
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What process is PAG involved in?
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Descending Pain Pathways
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Where does PAG synapse at?
|
Serotonic Neurons in Raphe Nuclei of Medulla
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Relation between nociceptor and mechanosensory neuron with second order projection neuron?
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Can both excite some second order projection neurons
|
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What type of fiber excites the inhibitory interneuron?
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A-Beta fiber
|
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C-fiber and A-gamma axons inhibit the inhibitory interneuron which means...?
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The Second order projection neuron is excited
|
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A-beta axon excites inhibitory inteneuron, which means...?
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The second order projection neuron is inhibited
|
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When the gate is closed and no sensory information, what is happening?
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Inhibitory interneuron is being excited by A-beta so it inhibits second order projection neuron
|
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When the gate is closed and touch alone is sensed, what is happening?
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Mecahnosensory (A-beta) is exciting the interneuron, inhibiting the 2nd order neuron
|
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When the gate is closed and pain and touch is experienced, what is happening?
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Mechanosensory neuron blocks the excitatory effects of nociceptor neuron on 2nd order projection neuron
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What is happening when the gate is open?
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Only pain. Nociceptive neuron maximally excites projection neuron by inhibiting interneuron
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What is referred pain?
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Pain perceived at a site that isn't a painful stimulus
|
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What is visceral pain?
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Pain perceived in the organs
|
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What is cutaneous pain?
|
Sensation of pain arising from the skin
|
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Job of the thermoreceptor?
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Nonnoxious (nonpainful) temperature sensations
|
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Heat TRP channels (2)?
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TRPV3, TRPV4
|
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Cold TRP channels (1)?
|
TRPM8
|
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Noxious (nociception) heat TRP channels (2)?
|
TRPV1, TRPV2
|
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Noxious (nociception) cold TRP channels (1)?
|
TRPA1
|
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Pathway for thermoreceptors?
|
Nearly identical to the pain pathway
|
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What are cold receptors coupled with?
|
A-gamma and C Fibers
|
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What are warm receptors coupled with?
|
C fibers
|
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What is Dorsal column-medial lemniscal pathway also called?
|
Mechanosensory pathway/Touch pathway
|
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What does a bitter taste indicate?
|
Potentially poisonous food
|
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What does a Sweet taste indicate?
|
Calorie-Rich Food
|
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What does a Salty taste indicate?
|
Electrolytes
|
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What does a sour taste indicate?
|
Possibly spoiled/unripe food
|
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What does a umami taste indicate?
|
"delicious flavor" (savory): Amino Acids
|
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4 structures involved with taste?
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Tongue, Pharynx, Epiglottis, Palate
|
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Where is the papillae found?
|
On the taste structures
|
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What is a single papilla made of?
|
Taste buds
|
|
What is a single taste bud made of?
|
Many taste receptor cells
|
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What is the taste receptor cell? (Its type)
|
Sensory cell
|
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Type of Papillae in the back part of the tongue?
|
Vallate or Circumvallate
|
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Type of papillae in the anterior 2/3rds of the tongue?
|
Fungiform
|
|
Type of papillae the posterior lateral edge?
|
Foliate
|
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How many taste buds does Fungiform papillae have?
|
Few
|
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How many taste buds does vallate papillae have?
|
250
|
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How many taste buds does foliate papillae have?
|
12-600
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How many taste receptor cells does each taste bud have?
|
50-150
|
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What type of cell is the TRC and what is its polarity?
|
Non-neuronal, Polar
|
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What is a microvilli? Where is it found?
|
Things that project into the taste pore. Found on the apical surface of taste receptor cell
|
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Life span of taste receptor cell?
|
2 weeks
|
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What is a tastant?
|
Disolved ion or molecule that stimulates taste receptor proteins
|
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Where doe we experience taste on our tongue?
|
Each taste has the same range of perceptibility
|
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What is transduction?
|
When a stimulus from the environment causes an electrical response in a sensory receptor cell
|
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What starts transduction for taste?
|
Tastant
|
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What starts AP for taste?
|
When gustatory axons receive neurotransmitter emitted by TRC
|
|
G-protein combination for Sweet tastes?
|
T1R2+T1R3
|
|
G-protein combination for umami tastes?
|
T1R1+T1R3
|
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How many types of G-protein bitter receptors are there?
|
30
|
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How does tastant (Na) for salt enter the TRC?
|
Through amiloride-sensitive sodium channels
|
|
How does tastant (H+) for sour enter the TRC?
|
H+ regulates some type of cation channel (Opens TRPP or closes K+)
|
|
Difference between Amiloride-Sensitive Na Channels and Na voltage gated channels (3)?
|
-not voltage gated
-open at rest -blocked by amiloride |
|
Name of g protein in transduction of bitter, sweet and umami?
|
gustducin
|
|
What activates TRP channel in bitter, sweet, umami transduction?
|
IP3
|
|
What is the TRP channel in bitter, sweet, umami transduction?
|
TRPM5
|
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What is the specific type of bitter TRC called?
|
T2R
|
|
Labeled line theory of TRC?
|
Each TRC responds to a single receptor type
|
|
Across-Fiber theory?
|
Each TRC can respond to more than one type of taste
|
|
Multimodal Across-Fiber theory?
|
Each TRC has many receptor types
|
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1 Kind of TRC to any nerve for across fiber theory?
|
Each TRC only codes for taste type, but the axons sending the information can be responding to more than 1 TRC at a time
|
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H+ typical tastant for what kind?
|
Sour
|
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Na+ typical tastant for what kind?
|
Salt
|
|
Quinine typical tastant for what kind?
|
Bitter
|
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Glucose typical tastant for what kind?
|
Sweet
|
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Glutamate typical tastant for what kind?
|
Umami
|
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What carries taste signal?
|
Cranial nerves VII, IX, X
|
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Where does cranial nerves XII, IX, X synapse onto for taste? And where?
|
Gustatory Nucleus in the medulla
|
|
Where does gustatory nucleus axons synapse onto for taste? and what?
|
Ventral posterior medial (VPM) nucleus of the thalamus in the thalamus
|
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Where does VPM neurons project to?
|
Gustatory and frontal cortex
|
|
Where are the majority of olfactory pathways?
|
Olfactory bulb
|
|
Organ of smell?
|
Olfactory Epithelium
|
|
Name of specific receptor of odorants?
|
Olfactory Receptor Neuron
|
|
Life span of ORN?
|
4-8 weeks
|
|
Type of cell is ORN?
|
Neuronal
|
|
What do supporting cells do in olfactory system (2)?
|
Detoxify toxins in mucus and contribute to mucus
|
|
Point of basal cells in Olfactory system?
|
Produce new ORN
|
|
Point of Bowman's Gland?
|
Produce mucus
|
|
How many axons and dendrites per ORN?
|
1
|
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What is on the end of the dendrite of the ORN?
|
A know with Cilia that protrude out
|
|
What structure does ORN neurons leave the Olfactory Epithelium in? And in what nature?
|
Axons leave through openings called Cribiforms in clusters
|
|
What is the cranial nerve for olfactory system? What is unique about it?
|
Cranial Nerve 1. There isn't a single Cranial nerve, but collectively, all the axons make up this nerve
|
|
Where does odorant detection occur?
|
In the cilia
|
|
Specific G-protein for Olfactory system?
|
G_olf
|
|
What does G_olf activate?
|
Adenylyl cyclase
|
|
What does Adenylyl cyclase synthesize (Olfactory)?
|
cAMP
|
|
What does cAMP then do (olf.)?
|
Bind to Cyclic Nucleotide (CNG) Channels
|
|
Binding to CNG Channels does what (olf.)?
|
Influx of Na^+ and Ca^2+
|
|
What does the Ca^2+ do (olf.)?
|
Binds to Ca^2+ activated Cl^- channels
|
|
Activation of Cl^- channels does what (olf.)?
|
Membrane depolarization
|
|
Where does the membrane depolarization first occur in the olfactory system?
|
Cilia. (NOT Dendrite, AP propagates there)
|
|
What is an odorant?
|
Airborne chemical stimulus
|
|
What is the g-protein coupled receptor odorant structure like?
|
Has 7 membrane-spanning domains
|
|
Where does odorant bind in relation to the cell?
|
Extracellular domains
|
|
Where is the g-protein interaction occurring?
|
Intracellular C-terminal
|
|
How many odorant types do most ORNs express?
|
1
|
|
How many ORNs can one odorant activate?
|
many
|
|
How does brain encode what kind of smell it is experiencing if there many ORNs can be activated by one odorant?
|
Through population coding. A certain odorant will create a certain response across ORNs that is unique to that odorant
|
|
Where is the second order neuron located (olf.)?
|
Olfactory bulb
|
|
What are the second order neurons called (olf.)?
|
Mitral cells
|
|
Where do ORNs synapes onto Mitral cells?
|
Glomerulus
|
|
Mitral cells form a bundle called what?
|
Lateral Olfactory Tract
|
|
What does the Lateral Olfactory Tract do?
|
Project to several brain structures
|
|
What does 3rd order projection neurons go to (olf.)?
|
Olfactory Cortex
|
|
What does 4th order projection neurons go to (olf.)?
|
Orbitofrontal Cortex
|
|
Where does 3rd order neuron synapse onto 4th order (olf.)?
|
In the Medial Dorsal Nucleus in the Thalamus
|
|
Where does the 2nd order neuron synapse onto the 3rd order (olf.)?
|
Olfactory tubercle
|
|
How many Glomeruli are there per olfactory bulb?
|
2000
|
|
How many ORNs go to one Glomeruli?
|
About 25,000
|
|
How many Mitral cells do Glomeruli converge onto?
|
25
|
|
Where do all ORNs expressing as type of odorant synapse to?
|
the same glomerulus
|
|
Two ways to map Olfaction encoding?
|
Temporal and with a map
|
|
What is ansomia?
|
Inability to detect a common odor
|
|
What can affect ansomia (3)?
|
Genetic defect, injury and age
|
|
Can humans scent-track?
|
Yes
|
|
Can humans improve smell with practice?
|
yes
|
|
Is sniffing behavior involved?
|
yes
|
|
Does each nostril provide distinct information?
|
yes
|
|
Do humans use inter-nostril information?
|
yes
|
|
What is a pheromone?
|
Chemicals released by a organism that affects another organism in the same species' behavior or physiology
|
|
What is the point of the Vomeronasal Organ do in relation with pheromones?
|
Involved in mating behavior
|
|
What is the point of the Grueneberg Ganglion in relation to pheromones?
|
Fear response
|
|
2 types of specialized coupled g-protein receptors in Vomeronasal Organs?
|
V1Rs and V2Rs
|
|
Main type of specialized coupled g-protein receptors in Grueneberg Ganglion?
|
V2Rs
|
|
Do human adults have a Vomeronasal Organ? If not, do we ever?
|
No. Only when we are embryos
|
|
What could play role of Vomeronasal Organ in humans? Why?
|
Olfactory Epithelium. There are two functional pheromone receptor genes (V1R-type) found there
|
|
Possible pheromones in humans (3)?
|
Menstrual cycles, sweat and affects on opposite sex, what estrogen/testosterone does on opposite sex's brain activity
|
|
What nerves are used in the Vestibulo-Occular reflex?
|
3, 4, and 6
|
|
What part of the ear is the vestibular labyrinth a apart of?
|
The inner ear
|
|
What does the vestibular labyrinth do?
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Maintains balance
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What does the cochlea do?
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Hearing
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What is endolymph?
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A fluid with high conc. of K^+ and low Na^+, like cytoplasm
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What structures make up the vestibular labyrinth (2)?
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Otolith Organs and Semicircular Canals
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How many otolith organs per vestibular labyrinth?
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2
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How many semi-circular canals per vestibular labyrinth?
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3
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what is the longest cillium on a hair cell called?
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Kinocilium
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How is the vestibular epithelium special in terms of charge?
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It has a polarized orientation
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How is depolarization caused within the Vestibular Labyrinth structures?
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Deflection towards the kinocillium.
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Function of the otolith organs?
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Detect head tilt and linear accelerations
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What is the sensory epithelium called in the Otolith Organ?
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Macula
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what is a utricle?
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A macula orientated parallel to the ground (The kinocilia are then perpendicular to the ground)
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Where is the utricle connected?
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To the semi-circular canals
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What kind of motion is the utricle sensitive to?
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Movement along the horizontal plane
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What is a saccule?
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macula orientated perpendicular to the ground (The kinocilia is then parallel to the ground)
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What is the saccule connected to?
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the cochlea
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What kind of motion is the saccule sensitive to?
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sensitive to gravity and vertical fall
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Semicircular Canal function?
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Detect angular accelerations
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Sensory epithelium in the semicircular canals?
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crista
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How many canals are found in the semicircular canal?
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3
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What is the name of the three canals within the semicircular canal?
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-Superior
-Posterior -Horizontal or lateral |
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What is the structure called that the semicircular canal meets up with the utricle?
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Ampulla
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What does the ampulla do?
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Houses the crista and the gelatinous structure called capula and hair bundle
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How many ampullas per semicircular canal?
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1
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What is a hair bundle (vest.)?
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cilia of hair cells
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How are kinocilia arranged in the macula?
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In different directions
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How are the kinocilia arranged in the crista?
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same direction
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How to hyperpolarize a cell (vestib.)?
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deflect the hair cell in which the kinocilia is the last cilium
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How to depolarize a cell (vestib.)?
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deflect the hair cell in which the kionocilia is the first cilium
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What kind of channels are activated when the kinocilia is deflected forward?
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Stretch-activated channels
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When the stretch activated channels are activated, what ion do they allow into the cell?
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Ca^2+
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What does the influx of Ca^2+ do (vestib.)?
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Open voltage gated Ca^2+ channels
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With the opening of voltage gated Ca^2+ channels, what happens?
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Neurotransmitter is released
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Two parts to the structure of the macula are?
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-Gelatinous cap
-otolithic membrane |
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What is the otolithic membrane?
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membrane embedded with otoliths (ear stones)
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What is the point of the macula with relation to head movement?
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To cause the cilia to bend with gravity due to the pressure the gelatinous cap and otolithic membrane applies
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How does hair cell bend in the crista?
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When head moves, endolymph fluid follows, but the cupula lags behind in opposite direction of head rotation
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What does the graph of the right and left semicircular AP look like when the head is rotated (any direction)?
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Exact opposites
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Otolith Organs and Semicircular Canals use which cranial nerve?
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8
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otolith organs synapse onto what (2)?
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The lateral vestibular nucleus
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semicircular canals synapse onto what?
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medial vestibular nucleus
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What does the 2nd order neuron project of the otolith organ that is going into the CNS?
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The cerebellum
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What does the 2nd order neuron project of the otolith organ that is going into the body?
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Limb motor neurons
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What does the 2nd order neuron project of the semicircular canals that is going into the CNS (2)?
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-VP nucleus of the thalamus
-Extraocular Motor Neurons |
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What neurons (numbers) does the extraocular motor neurons go to?
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3, 4, 6
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What does the 2nd order neuron project of the semicircular canal that is going into the body?
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Neck motor neurons
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What tract does the neck motor neurons and the extraocular motor neurons use?
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Medial longitudal fasciculus
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What is Vestibulo-Ocular Reflex (VOR)?
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Maintains focus of eyes while rotating head
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What muscles move eye left or right in VOR (2)?
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lateral rectus (temporal side of eye) or medial rectus (nasal side of eye)
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What does nerve 3 synapse onto for the extraocular motor neurons?
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Oculomotor Nucleus
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What does nerve 4 synapse onto for the extraocular motor neurons?
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Trochlear Nucleus
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What does nerve 6 synapse onto for the extraocular motor neurons?
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Abducens Nucleus
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What does In Vitro mean?
|
In cell culture outside of animal
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What does In Vivo mean?
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In the animal
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What does pharmacology mean?
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How a drug affects an animal
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What causes axons to form in relation to actin?
|
The depolymerization of acting
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What causes axons to form in relation to Microtuble?
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The stabilization of microtubles
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What protein is essential to producing axons?
|
Cdc42
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What happens when Cdc42 is inhibited?
|
Lack of axon development and smaller brain (due to less axons being produced)
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What protein recognizes Microtubles in axons?
|
KIF5
|
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What protein recognizes microtubles in dendrites?
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KIF17
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What keeps large molecules from entering the axon?
|
A actin wall forms at beginning of axon once it becomes polarized (mature)
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