Physiology quiz 1

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Physiology quiz 1
2013-02-26 13:24:43
Physiology t1

Physiology test one: cell membranes, body water compartments, PNS, CNS, Muscle Physiology
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  1. body water
    • 60% of total body weight (all but adipose cells are 75-85% water)
    • good solvent: heat transfer, high specific heat, lubrication
  2. Protein in cells
    • 10-20% of cell mass.  Found everywhere in the cell. 
    • Catalyst (enzymes), Structure (cytoskeleton), Transport, Transmission of info (change in shape to send signals), Reaction coupling (spontaneous joins with non-spontaneous)
  3. cytoskeleton
    made of cell proteins.  Tinker toys that are the framework that give cell structure and shape.  Cilia and Flagella are microfilaments and proteins. 
  4. Types of proteins in cell membrane (2)
    • Integral are membrane-spanning (channels)
    • Peripheral are one one side or the other (catalysts or anchor cytoskeleton)
  5. Integral proteins
    • protrude all the way throught the cell membrane and act as channels, some selective.
    • Include cell-surface receptors
  6. Peripheral proteins
    attached to one side or other of the cell membrane, do not span entire membrane.  Are catalysts or anchors for cytoskeleton.
  7. cell-surface receptors
    membrane-spanning (integral) proteins that transmit information.  Ligand attaches to make a reaction. 
  8. Ligand
    • attaches to a cell-surface receptor (integral protein) to form a complex and create a reaction. 
    • Can be a neurotransmitter, chemical messenger, hormone, etc.
  9. Lipids in cells
    • 2% of cell mass except in adipose cells. 
    • Most of cell- and organelle-membrane (phospholipid and cholesterol)
    • make up: steroid hormones (cortisol, estrogen, testosterone), bile (breaks down lipids), myelin sheaths of nerve cells (insulates axons to speed impulses), fat-soluble vitamins (A, D, E, K)
  10. Phospholipid bilayer
    • Phosphate (hydrophilic), glycerol and fatty acid tails (hydrophobic). 
    • Lipid-soluble small molecules go right through (CO2, O2).  Polar or big can't go through. 
  11. Adipose cells
    triglycerides store fat to use in the future.  They make up as much as 95% of lipid cell mass.
  12. Carbohydrates
    • less than 1% of cell mass in most cells.  Includes a small amount of glucose stored as glycogen (usu liver and skeletal muscle). 
    • Glucose also dissolved in blood plasma and fluid surrounding cells
  13. glucose
    main energy source for cells.  Stored as glycogen primarily in liver and skeletal muscle cells.  Also dissolved in blood plasma and fluid surrounding cells. 
  14. Monosaccharides
    simplest carbohydrates.  Glucose, fructose and galactose. 
  15. Disaccharides
    two bonded carbohydrates.  Sucrose and lactose. 
  16. Polysaccharides
    most complicated carbohydrates.  Glycogen.  Branched, so molecules can be pulled off lots of places at once. 
  17. Inorganic substances in cells
    • Most importantly electrolytes.  (Any molecular substance which in solution will dissociate into ions). 
    • Na, K, Cl, Ca, bicarbonate. 
    • Deals in muscles, nerves, hydration and pH
  18. Membrane potential (ion balance) in cells (Na, K, Cl)
    • Na+ MUCH higher in extracellular fluid
    • K+ MUCH higher in intracellular fluid
    • Cl- MUCH higher in extracellular fluid
  19. Extracellular fluids
    • watery environment outside of cells.  Interstitial (surrounds cells and tissues), intervascular (in vessels), trans-cellular (body cavities such as CSF and interocular fluid).
    • 20% of the 60% that is water in the body. 
  20. Intracellular fluid
    • watery environment inside of cells.  2/3 of body water. 
    • 40% of the 60% that is water in the body.
  21. Passive processes that bring things in and out of the cell (4)
    • Process that requires no energy
    • Diffusion (high concentration of solute to low)
    • Faciliated diffusion (uses carrier protein or channel)
    • Osmosis (water moving--from low solute concentration to high)
    • Filtration (depends on pressure)
  22. Active processes that bring things in and out of the cell (2, 2, 3)
    Uses ATP.  Active transport (primary and secondary) and Cytosis, consisting of Endocytosis (Phagocytosis, pinocytosis and recoptor mediated endocytosis) and Exocytosis
  23. Diffusion
    Kinetic movement of molecules from higher concentration to lower concentration. Passive process, requiring no ATP.  Molecules pass directly through or through channel proteins. 
  24. Membrane diffusion
    • Hydrophobic molecules (O2, CO2, N2, etc) pass through membrane (MW less than 100-200)
    • small uncharged polar molecules (H2O, indole, glycerol) pass through difficultly
    • Large uncharged polar molecules and ions can't pass through.
  25. Ways of simple diffusion
    • directly through lipid bilayer
    • through protein channels of integral proteins
  26. Aquaporin
    special channel just for water that prevent other ions and solutes from passing.  water-channels. 
  27. facilitated diffusion
    • selective carrier proteins assist in movement of molecules from higher concentration to lower concentration
    • Uses two types of integral membrane proteins: carrier proteins (permeases or transporters) and ion channels
  28. carrier proteins
    integral membrane proteins in facilitated diffusion that undergo conformational changes and bind to allow specific molecules into the cell.
  29. Ion channels
    • integral membrane proteins in faciliated diffusion that open and allow solute to pass, but don't bind solute or change shape (faster than carrier proteins).  Specific, some have gates. 
    • Can be voltage-generated or ligand-gated on the extracellular or intracellular side. 
  30. Osmosis
    passive movement of water through a semi permeable membrane from the dilute solution to the concentrated solution.  The water not the solute is moving. 
  31. Osmotic pressure
    • force put on water level to prevent osmosis from occurring. 
    • Adding particles to a concentrated solution causes an increase in pressure.  More solute equals higher pressure required to stop osmosis
  32. effective osmotic pressure
    tone.  Only includes nonpermeable membranes--anything permeable doesn't go towards effective pressure. 
  33. Tonicity
    effective osmotic pressure
  34. Isotonic pressure
    effective osmotic pressure equals solution in RBCs
  35. Hypotonic pressure
    • effective osmotic pressure is less than the solution in RBCs, causing water to enter and cells to swell or lyse. 
    • More solute inside, water moves into the cell.
    • Good for dehydrated cells
  36. Hypertonic pressure
    • effective osmotic pressure is greater than the solution in the RBCs.  Water exits the cell and the cell shrivels. 
    • More solute outside of cell.  Water moves out and cell shrivels.
    • Good for edema
  37. Filtration
    • passive process caused by hydrostatic pressure (the beating heart).  Pressure forces liquids and small molecules through a membrane (Kidneys)
    • Does not rely on concentration gradient (pressure)
    • Large molecules do not go through. 
  38. Active transport
    transport that uses ATP.  Primary (uses ATP directly) or secondary (uses ATP to make a concentration gradient and uses that to move molecules). 
  39. Primary active transport
    ATP directly consumed, such as sodium-potassium pump
  40. Secondary active transport
    • usually uses the energy of an ion gradient to move second solute.  Indirect use of ATP (establish the gradient, then pick up a hitchhiker when coming back in.  Glucose absorption in gut)
    • Includes symport (both molecules going in same direction) and antiport (molecules going in opposite directions)
  41. Sodium potassium pump
    three sodium out, two potassium in.  Intracellular Na is low and intracellular K is high.  Requires direct input of ATP--secondary active transport.
  42. Membrane potential
    voltage across a membrane.  Inside the cell is negative and outside is positive.  Sodium potassium pump contributes but increased permeability of membrane to potassium is primary reason (leaky--potassium out fast)
  43. Symport
    channel protein where two or more particles move in the same direction (glucose catches a ride with sodium)
  44. antiport
    • coupled transport in which two or more particles move in opposite directions.  ADP/ATP exchanger--1:1 exchange across inner mitochondrial membrane
    • Na/Ca exchanger--removes cytoplasmic calcium (one calcium for three sodium)
  45. Glucose transport from lumen of GI to blood
    catches a ride with sodium (secondary active transport through a symport) moves into the cell, where the high concentration of gluocose moves down its concentration gradient to interstitial
  46. cytosis
    • requires ATP.  Includes endocytosis (phagocytosis, pinocytosis, receptor-mediated) and exocytosis. 
    • large particles moving in and out of the cell. 
  47. Endocytosis
    large particles moving into the cell.  Requires ATP.  Includes Phagocytosis, Pinocytosis and receptor-mediated endocytosis. 
  48. Exocytosis
    Excretion of waste products and secretion of manufactured substances.  Vesicle breaks off of golgi to fuse with cell membrane.  Requires ATP.
  49. Phagocytosis
    Active transport where cells engulf solid substances (cell eating) by creating a food vacuole from the cell membrane
  50. Pinocytosis
    active transport where cells engulf liquid substances (water and other solutes) (cell drinking) by creating a food vacuole from the cell membrane.
  51. Receptor-mediated endocytosis
    active process where specialized protein receptors bind to ligands specific to receptor (hormones eg insulin, iron and cholesterol).  Once coated pit is full the vacuole breaks off
  52. What was wrong with Kiwi? ataxia, ventral neck flexion, lethargy
    • Slightly high sodium, VERY low potassium.  Hypokalemia.  Cell more negative, harder to reach threshold, nerves not firing. 
    • Adrenal gland tumor causing excess aldosterone.  Called Conn's Disease.
  53. Parts of a neuron
    • Cell body (soma)
    • Dendrites (recieve stimulus to cell body)
    • Axons (conducts stimulus away from cell body to effector
  54. Myelin sheath
    • cell membrane of neuroglia cells wrapped around nerve process to speed up nerve contraction by insulation. 
    • Oligodendrocytes in CNS
    • Schwann Cells in PNS
  55. myelin sheath cells in CNS
  56. myelin sheath cells in PNS
    Schwann cells
  57. Neurolemma
    guts of schwann cell pushed up into one spot where it is wrapped around a nerve.  Can help with regeneration
  58. Nodes of Ranvier
    spaces between schwann cells where there is no covering.  Between beads.  Impulse jumps from one to the next.
  59. Unmyelinated fiber
    Where schwann cells surround axons like the blob
  60. myelinated fiber
    a process having a myelin sheath, where a cell is wrapped many times around an axon to insulate and speed up nerve function.
  61. Clinical relevance of damaged myelin
    • can be damaged by toxins, post-natal malnutrition, MS, etc.  Kills myelin sheaths. 
    • Causes loss of motor and sensory fucntion, and eventual paralysis. 
  62. Two ways that nerves conduct information
    • down an axon (electrically via action potentials)
    • across a synapse (electrical or chemical)
  63. Action potential
    • In response to proper stimuli cell membrane potential reverses (- to +), then returns. 
    • Stimuli causes initial change, threshold reached, voltage-gated Na channels open, increase reverses membrane potential to +, voltage-gated potassium channels open, loss of + causes potential to return to -, hyperpolarization occurs (too much -) and cell returns to normal. 
  64. steps of an action potential
    • Threshold stimulus
    • depolarization
    • repolarization
    • hyperpolarization
    • return to resting phase
  65. Threshold stimulus
    when a stimulus (physical, chemical or electrical) is strong enough to cause an action potential. 
  66. Depolarization
    the reversal of the resting membrane potential (after-stimulus switch to +)
  67. repolarization
    return of the membrane potential to normal resting values (inside is - and outside is +)
  68. Hyperpolarization
    Exit of potassium makes inside of cell too negative for a while until resting conditions can be reestablished by the sodium-potassium pump. 
  69. Reestablished resting membrane potential
    caused by sodium-potassium pump
  70. Refractory periods
    • periods of time when nerve cell is insensitive to stimuli until recovered from action potential. 
    • absolute refractory period-completely insensitive, stopping impulse from moving backward)
    • relative refractory period-a strong enough signal could cause another depolarization but less sensitive. 
  71. Travel of action potential
    • Begins at top of axon near cell body.  The membrane potential of adjacent areas is altered by local movement of charge which allows travel. 
    • "propagation".  voltage change spreads due to attractiveness of charges.  Spreads only one direction due to refractory peroids (unidirectional impulse conduction)
  72. unidirectional impulse conduction
    action potential can only travel in one direction due to refractory period.
  73. saltatory conduction
    the wave of action potentials from node to node. 
  74. Speed of conduction of axons depends on
    • myelination and diameter of axon because of:
    • higher velocity action potentials
    • less internal resistance to flow of current
  75. synaptic transmission
    • one of two ways that nerves relay information
    • specialized junctions where information is exchanged between neurons or between a neuron and the cell it innervates
    • two types: electrical (voltage) and chemical (neurotransmitters)
  76. electrical synapses
    gap junctions between cell membranes of adjacent neurons that permit ionic exchange between cytoplasm.  Creates electrical bridge when voltage changes, carrying positive charge to polarize post-synaptic cell--faster, but DO NOT have gain.
  77. Synapse Gain
    when signal is boosted as it goes along--action potential strenthens.  Electrical does not have it.
  78. Chemical synapse
    • presynaptic neuron releases neurotransmitters to carry action potential.  Can be excitatory or inhibitory (hyperpolarization)
    • Includes: synaptic cleft, presynaptic neuron, post synaptic neuron, terminal bouton (synaptic end bulb), synaptic vesicles, receptors
  79. synaptic cleft
    area between neurons
  80. synaptic vesicles
    boats that carry chemicals across synaptic cleft. 
  81. receptors
    spot on post synaptic neuron that receives neurotransmitters
  82. Reuptake
    arranging to withdraw neurotransmitters back into presynaptic neuron so that reaction stops.  Some are broken down by enzymes (Acetylcholine broken down by acetylcholinase)
  83. excitatory neurotranmitters
    causes a reaction.  Usually positive.  Example, ligand-gated channel lets in positive sodium ions.  One postsynaptic membrane may have multiple presynaptic neurons ennervating it.  Whichever is more active determins excitation or inhibition.
  84. inhibitory neurotransmitters
    stop a reaction.  Usually negative.  Example, ligand-gated channel lets in negative chloride ions or out positive potassium ions.  More negative=action potential not reached.  One postynaptic membrane may have multiple presynaptic neurons ennervating it.  Whichever is more active determins excitation or inhibition.
  85. Hilock
    trigger zone.  Where excitatory stimulus creates an action potential.
  86. ESPS
    excitatory post synaptic potential
  87. ISPS
    inhibatory post synaptic potential
  88. Post synaptic action potential sequence (IPSP)
    • membrane potential is more negative
    • further away from the threshold
    • action potential is not generated.
  89. Post synaptic action potential sequence (EPSP)
    • membrane depolarization more positive
    • reaches threshold
    • voltage-gated sodium channels in axon open
    • depolarization
    • action potential is generated
  90. Synapse between a neuron and a muscle
    • always excitatory
    • Neurotransmitter is acetylcholine
    • a constant state of stimulation
  91. What was wrong with Max?  Sawhorse stance from stepping on a nail.  Presented 3-10 days later. 
    Botulinum (tetanus) toxin blocks inhibatory release to create constant excitation.
  92. Neurotransmitters
    • Chemical messengers between neurons.  Most are amino acids, monamines (modified amino acids) or polypeptides (proteins). 
    • Examples include: acetylcholine (neuro-muscular), norepinephrine and epinephrine (adrenal, autonomic), dopamine (CNS transmitter), Gamma-aminobutyric (GABA), Glycine
  93. Nervous vs endocrine system
    • Both monitor and react to stimuli to maintain homeostasis. 
    • NS is rapid, fast-acting and often short-lived
    • ES acts slower via blood-borne chemical signals (hormones) and its actions are longer-lasting. 
  94. Nervous system
    • Functions: Sensation, Integration, Reaction
    • Divisions: CNS-> Brain, Spinal cord
    • PNS->Sensory neurons, motor neurons->Parasympathetic (cholinergic), Sympathetic->adrenergic->alpha, beta
  95. CNS
    Brain and spinal cord
  96. PNS
    Sensory and Motor.  Cord-like nerves that link CNS with the rest of the body (Cranial nerves and spinal nerves).
  97. Cranial nerves in PNS
    impulses to and from the brain
  98. Spinal nerves in PNS
    take impulses to and from the spinal cord
  99. Afferent nerves
    • sensory nerves that travel towards the CNS in ascending tracts from periphery to CNS.  Dorsal nerve root ganglion.
    • sensation is "awareness of a stimuli".  3 parts.  Physical stimuli, transformation into a nerve impulse, response (perception or experience of sensation)
    • Senses: vision, hearing, touch, taste, smell, vestibular balance, somatic (pain, temperature, itch, proprioception)
  100. Efferent nerves
    • motor nerves away from CNS.  Travel in desceding tracks from CNS to periphery.  Ventral nerve root ganglion.
    • Somatic or autonomic
  101. nocioception
    perception of pain or potentially damaging stimuli.  Pathways are extremely complex and important to survival.
  102. Somatic nervous system
    • voluntary, SKELETAL MUSCLE
    • SINGLE efferent neuron
    • always excitatory
    • acetylcholine
    • controlled by cerebrum
  103. autonomic nervous system
    • involuntary, SMOOTH OR CARDIAC MUSCLE and GLANDS
    • multiple efferent neurons (pre- and post-ganglionic synapses)
    • acetylcholine or norepinephrine
    • excitatory or inhibitory
    • controlled by pons, hypothalamus, medulla oblongata
  104. Sympathetic autonomic nervous system
    • Fight or flight. 
    • Thoracolumbar to parasympathetic chain
    • short pre-ganglionic fiber, Acetylcholine (Cholinergic) with Nicotinic receptor
    • long post-ganglionic fiber, Norepinephrine (Adrenergic) with alpha and beta receptors
    • Sometimes to sweat glands: post=acetylcholine with muscarinic receptor.
    • Pre goes to adrenal gland, which secretes norephinephrine and epinephrine into the blood
  105. parasympathetic autonomic nervous system
    • rest and digest
    • Craniosacral to target tissue
    • long pre-ganglionic fiber, Acetylcholine with nicotinic receptor
    • short post-ganglionic fiber, acetylcholine with muscarinic receptor
  106. cholinergic
    Neurons releasing acetylcholine and synapses that use acetylcholine (uses nicotinic and musarinic receptors)
  107. Adrenergic
    neurons and synapses that use norepinephrine (uses alpha and beta receptors)
  108. Sypathetic NS neurotransmitter receptors
    • Pre: acetylcholine, nicotinic
    • Post: 1. norephinephrine, alpha and beta
    • 2.  (sweat, BV) acetylcholine, muscarinic
    • 3. Adrenal gland, epinephrine and norepinephrine into blood, goes to find alpha and beta receptors
  109. Parasympathetic receptors
    • Pre: acetylcholine, nicotinic
    • Post: acetylcholine, muscarinic receptors
  110. Cranial nerves that supply parasympathetic
    • CN III Oculomotor (smooth muscle/glands of head)
    • CN VII Facial (smooth muscle/glands of head)
    • CN IX Glossopharyngeal (smooth muscle/glands of head)
    • CN X Vagus (Thorax, neck, abdomen)
  111. Sympathetic or Parasympathetic
    heart rate
    • sym: increase
    • Para: decrease
  112. Sympathetic or Parasympathetic
    force of heart contractions
    • sym:increase
    • Para:no effect
  113. Sympathetic or Parasympathetic
    Diameter of bronchioles
    • sym:increases (dilates)
    • Para:decreses (constrict)
  114. Sympathetic or Parasympathetic
    Diameter of pupil
    • sym:increses (dilates)
    • Para:decreases (constricts)
  115. Sympathetic or Parasympathetic
    gastrointestinal motility, secretions and blood flow
    • sym:decreases
    • Para:increases
  116. Sympathetic or Parasympathetic
    diameter of skin blood vessels
    • sym:decreases
    • Para:no significant effect
  117. Sympathetic or Parasympathetic
    diameter of muscle blood vessels
    • sym:decreases
    • Para:no significant effect
  118. Sympathetic or Parasympathetic
    diameter of blood vessels to kidney
    • sym:decreases
    • Para:no significant effect
  119. Sympathetic or parasympathetic
    • sym: urine retention
    • para: urine release
  120. sympathetic or parasympathetic
    sweat glands
    • sym: local sweating
    • para: generalized
  121. sympathetic or parasympathetic
    male reproduction
    • sym: ejaculation
    • para: erection
  122. sympathetic or parasympathetic
    female reproduction
    sym or para: depends on stage of cycle
  123. Reflex
    • automatic or unconscious response to appropriate stimuli. 
    • To protect body and maintain homeostasis
    • Somatic (skeletal muscle contraction) or autonomic (smooth muscle, cardiac or endocrine)
  124. Reflex arc
    • The pathway of nerves in a reflex, from stimuli to spinal cord to effector organ. 
    • Can include: receptor
    • sensory neuron
    • integration center (monosynaptic or polysynaptic with interneurons)
    • motor neuron
    • Effector
  125. monosynaptic reflex arc
    • simplest.  2 neurons, 1 synapse. 
    • Stretch reflex, patellar tendon
  126. polysynaptic reflex arc
    • 3 or more neurons (interneurons) and 2 or more synapses in the integration center. 
    • Flexor (withdrawal) reflex
  127. Flexor (withdrawal) reflex
    polysynaptic reflex that causes a limb to withdraw when it encounters pain
  128. Parasympathetic autonomic (visceral) reflexes
    gastric and intestinal, defecation, urination, direct light reflexes, swallowing, coughing, sexual arousal
  129. Sympathetic Autonomic (visceral) reflexes
    cardioaccelaratory, vasomotor, pupillary, ejaculation
  130. What was wrong with Melena?  Extreme back pain, ataxia progressing to paralysis
    Intervertebral disk disease.  Hemilaminectomy to remove the material that was pushing on the spinal cord.  Rehab.
  131. What was wrong with Fifi?  SLUD (salivation, lacrimation, urination, defecation), vomiting, anxiety, seizures, miosis, dysapnea, bradycardia, muscle tetany
    • ate a toxin?  Overstimulation of the parasympathetic system.  Acetylcholinesterase not being broken down. 
    • Organophosphate and Carbamate toxicity
    • Atropine
  132. Antagonist
    • drug that binds/blocks ligand site but does not produce an effect. 
    • Somatic: poison dart!  Curare.  Blocks skeletal contraction
    • Parasympathetic: Atropine.  Stops heart from slowing down (bradycardia)
  133. Agonist
    • drug that binds to ligand site and creates the same response. 
    • Somatic: seizures, muscle tremors
    • autonomic: vomiting, respiratory and heart effects
    • Ivermectin acts like an inhibatory neurotransmitter causing depression, coma, loss of voluntary movement and death. 
  134. Beta blockers
    reduce the effect of sympathetic nervous system (lower BP), block norepinephrine
  135. sodium channel blockers
    • Tetrodotoxin (pufferfish)
    • Saxitoxin (dinoflagellates)
    • Procaine and Lidocaine
  136. Regions of the brain (5-7)
    • Brainstem (Medulla, Pons, midbrain) (less evolved)
    • Diencephalon
    • Cerebrum (more involved)
    • Cerebellum
    • Spinal cord
  137. Diencephalon
    Thalamus (circle), hypophysis (pituitary), hypothalamus, epithalamus
  138. Cerebrum (Telencephalon)
    • "higher functions" (learning, intelligence, awareness)
    • initiates skeletal muscle movement
    • Frontal, Parietal, Occipital, temporal lobes, divided by longitudinal fissure into two hemispheres
    • Grey matter (outside), white matter (inside), basal nuclei
  139. cerebral cortex (3 areas)
    • grey matter in the cerebrum (outside).
    • Nervous reactions that result in consciousness
    • High degree of educatability
    • Motor area, sensory area, association (integration) area
    • voluntary at very front, visual at very back of cerebrum, auditory at center of hemisphere
  140. Somatosenses or somesthetic senses
    • senses that include receptors everywhere.  3 types: cutateous, proprioception and kinesthesis. 
    • First, second and third-order fibers= most common arrangement (can be more or less)
    • receptor (1) to spinal cord or brain stem (2) to thalamus, cerebellum, somatosensory cerebral cortex.
  141. Cerebral white matter (3 types)
    • myelinated nerve fibers beneath cerebral cortex. 
    • 3 types:Association (connect parts of cerebrum), Commissural (connect 2 hemispheres), Projection (connect cortex with other parts of the brain and spinal cord
  142. Basal nuclei (basal ganglia)
    • separate, large pools of neurons deep in cerebral hemispheres 
    • control semi-voluntary movements (walking and running)
  143. Cerebellum
    • just caudal to cerebrum.
    • coordinated movement, balance, posture, and complex reflexes. 
    • Compares intended movement with actual movement.  Input from visual cortex, inner ear, motor cortex, muscle, joint, foot pad, tendon, eye, etc. Spinocerebellum, cerebrocerebellum and vestibulocerebellum
  144. Spinocerebellum
    input to cerebellum, to brainstem and corticospinal pathways.  Execution of coordinated movement.  Center of cerebellum.
  145. Cerebrocerebellum
    Input to cerebellum.  To motor cortices.  Planning coordinated and properly timed movement sequences
  146. vestibulocerebellum
    input to cerebellum, to vestibular nuclei.  coordinated balance and eye movement. 
  147. What was wrong with Samantha?  Uncoordinated, non-progressive locomotory movements (ataxia).
    Cerebellar hypoplasia.  Tiny, underdeveloped cerebellum.
  148. Diencephalon
    • nervous system passageway between primitive brain stem and cerebrum.  "Between brain". 
    • Thalamus (circle), epithalamus, hypothalamus, hypophysis (pituitary), third ventricle. 
  149. Thalamus
    • in diencephalon.  Sends sensory information to the brain.  Relay station for regulating sensory info.  Integrates motor from cerebellum and basal nuclei. 
    • 4 groups, don't learn the names. 
  150. hypothalamus
    • Part of diencephalon, just below thalamus.  Interfaces between NS and ES.  Functions in autonomic activities and behavior. 
    • Hunger, thirst, blood pressure, rage, anger, reproduction, circadian rhythms, sleep/wake, temperature control.
  151. Epithalamus
    • part of diencephalon. 
    • Olfactory (smell) correlation center and pineal gland (circadian rhythms)
  152. Pineal gland
    in epithalamus in diencephalon, secretes melatonin, aids in circadian rhythms. 
  153. Hypophysis (pituitary gland)
    in diencephalon.  Master endocrine gland, regulates other endocrine glands. 
  154. brain stem (3 parts)
    • connection between the rest of the brain and the spinal cord.  Most primitive. 
    • midbrain (mesencephalon), pons, medulla oblongata
  155. Midbrain, mesencephalon
    part of brain stem.  Contains auditory and visual reflex center, nuclei of two cranial nerves and several decending tracts
  156. Medulla and pons
    part of brain stem.  Contain ascending and descending pathways, sensory and motor nuclei for all cranial nerves in brain stem (except two in midbrain), most of postural reflexes (hopping, righting, placing), reflex centers for autonomic visceral functions (heart rate, blood vessels, GI motor and GI sensory)
  157. Pons
    • part of brain stem. 
    • contains several cranial nerve nuclei, two nuclei controlling respiration called the apneustic center and pneumotaxic center (regulate pace of respiratory movements)
  158. Pneumotaxic and Apneustic centers
    respiratory center in pons, in brain stem that regluates pace of respiratory movements. 
  159. Medulla contains three major groups of nuclei
    • Reticular formation
    • cranial nerves
    • relay station from sensory and motor pathways. 
  160. Reticular formation
    • Medulla through pons and midbrain to caudal diencephalon.  Part of medulla. 
    • Loosly clustered neurons.  Coordinated reflexes and simple behavior: GI response, respiratory activities, cardiovascular functions, maintinence of tone, balance posture; pain, waking-up arousal
  161. Medulla
    • part of brain stem.  Contains nuclei that act as relay stations from sensory and motor pathways and 5 cranial nerve origins
    • VIII Vestibulocochlear
    • IX glossopharyngeal
    • X vagus
    • XI accessory
    • XII hypoglossal
  162. Reticular activating system (RAS), ascending RAS
    • thin line inside reticular formation inside medulla inside brainstem. 
    • Sends impulses through thalamus to cerebral cortex.  Excitatory (wake-up arousal).  inhibited during sleep. 
    • Anesthetics may block RAS. 
    • Direct stimulation makes pain responses. 
  163. What was wrong with Gertrude?  Falls asleep. 
    not enough norepinephrine--negative feedback for excitatory response. 
  164. Damage to brain stem makes you:
  165. damage to cerebellum makes you
  166. damage to forebrain makes you
    • surprisingly normal.  Can cause odd symptoms such as altered behavior, seizures, compulsive circling (toward lesion), head pressing, bad reflex responses on opposite side.
    • Neoplasm, Astrocytoma. 
  167. Emetic center
    in medulla.  takes in sensory information from the body and causes vomiting. 
  168. CTZ (Chemoreceptor Trigger Zone)
    fourth ventricle, sends information to the emetic center to cause vomiting if there are toxic chemicals in the body. 
  169. Brain ventricles
    • fluid-filled spaces in brain developed from lumen of embryonic tube. 
    • Lateral (left and right), third (connected to laterals by interventricular formamina), fourth connected to thrid by mesencephalic aqueduct, connects to subarachnoid space.  Lateral apertures. 
  170. choroid plexus
    tuft of capillaries that protrudes into the lumen of each ventricle.  Frms most of the cerebrospinal fluid. 
  171. cerebrospinal fluid (CSF)
    • continuously formed, circulated and reabsorbed in the spaces of the nervous system. 
    • circulation includes:lateral ventricles, interventricular formina, third ventricle, mesencephalic aqueduct, fourth ventricle, lateral apertures, subarachnoid space
  172. circulation of CSF
    • lateral ventricles
    • interventricular formina,
    • third ventricle,
    • mesencephalic aqueduct,
    • fourth ventricle,
    • lateral apertures,
    • subarachnoid space
  173. What was wrong with lexie?  Seizures and round head with open fontanelle (soft spot)
    • Hydrocephalus--water on the brain
    • Cranium expands due to lack of reuptake of CSF. Adults don't have dome, but severe neurological signs. 
  174. Meninges/layers over the brain
    • skin
    • periosteum
    • bone
    • dura mater tough fibrous outer layer
    • arachnoid spiderwebby middle layer
    • pia mater very thin, goes into grooves
  175. Steps of sensory reception (3)
    • physical stimuli
    • transformation of stimulus into nerve impulse
    • response to sensation as perception or conscious experience of sensation
  176. Senses (6, 4)
    • Vision
    • hearing
    • touch
    • taste
    • smell
    • balance (vestibular)
    • Somatic: nocioception, temperature, itch, proprioception (receptors everywhere)
  177. Classes of sensory receptors (5)
    • mechanical-touch, proprioception (muscle stretch, contraction), joint position, hearing, balance
    • chemical-itches, taste and smell
    • nocioceptors-pain
    • thermal-hot or cold
    • electromagnetic-photoreceptors (electromagnetic energy)
  178. mechanical sensory receptors
    touch, proprioception (muscle stretch or contraction), joint position, hearing, balance
  179. chemical sensory receptors
    itch, taste, smell
  180. electromagnetic sensory receptors
    photoreceptors sense electromagnetic energy
  181. Sensory receptor types
    • chemoreceptor-detect chemical signals
    • mechanoreceptors-detect distortion in cell membrane
    • photoreceptor-light into electrical signals
  182. types of sensory mechanoreceptors
    • Proprioceptors (muscles, tendons, ligaments, joints, sense stretch, angles)
    • tactile receptors (touch, pressure vibration)
    • baroreceptors (changes in pressure within internal environment.  in arteries, lungs, colon and bladder)
  183. sense of smell
    • chemoreceptors on the cribiform plate of the ethmoid bone (back of nose) detect volatile chemicals in solution when they dissolve in mucous membrane of the olfactory epithelium (bind to receptors to open sodium channels). 
    • It is percieved in olfactory bulb of the cerebral cortex. 
    • First, secondary and third-order neurons
  184. Olfactory receptors
    • Unmyelinated axons. 
    • First-order: olfactory nerve (cranial nerve I)
    • Secondary neurons: olfactory bulb
    • Third-order neurons: primary olfactory cortex.  Send projections to thalamus, basal forebrain and limbic system
  185. Taste buds
    • papilla of the tongue, palate, pharynx, epiglottis and upper third of the esophagus. 
    • Consist of a taste pore with microvilli extending into it, innervated by gustatory (taste) neurons. 
    • Excitable.  Different channels for each taste, but cell depolarizes.  Voltage-gated NA, K and Ca channels on cell surface cause exocytosis of neurotransmitters to excitatory, gustatory neuron. 
  186. 5 tastes
    salty, sour, sweet, bitter, umani (MSG)
  187. gustatory
  188. Where is taste perceived?
    The gustatory center of the cerebral cortex
  189. Where does perception of sound occur?
    auditory cerebral cortex
  190. Where are the receptors for hearing?
    little hairs in the cochlea in the organ of corti.  Bending of hairs opens channels to create an action potential. 
  191. where is vestibular sensation perceived?
    vestibular area of the cerebral cortex
  192. Where are the receptors for vesibular sensation?
    semicircular canals in the vestibule
  193. Pathway through the retina
    • light goes through ganglion cells (optic nerve), amacrine cells, bipolar cells, rods and cones
    • action potential comes from rods and cones, to bipolar cells, ganglion cells and to the optic nerve
  194. three visual pathways of optic ganglions
    • 1. perception of form, color, motion, orientation, depth
    • 2. Pupillary reflexes and orientation on visual targets
    • 3. regulation of physiological rhythms (light and dark cycles)
  195. Visual pathway: Left-field vision is perceived on the ____________side of the brain
    right.  Vision crosses to the other side of the brain through the nose-area.  perceived in opposite cerebral cortex
  196. Where does vision go after the visual cortex? 
    • other occipital lobes for complex processing
    • parietal and temporal lobes for higher processing and integration with other senses
  197. 3 types of somatosenses
    • cutaneous (touch, pressure, vibration, temperature)
    • proprioception (body position)
    • Kinesthesis (body movement, pain, tickle, itch)
  198. Pain
    • nocioception, somatosensory. 
    • Direct from damaged tissue
    • indirect from chemicals released from damaged tissue
    • Not perceived until the cerebral cortex
  199. temperature
    • thermoreceptors, somatosensory.  Changes in temperature but only gentle temps--damaged tissue stimulates a pain receptor. 
    • TONIC firing rate--always firing, go faster or slower as temperature changes. 
    • Not perceived until the cortex
  200. motor system
    • transforms neural information into physical energy
    • Lower (brains stem/spinal cord to effectors) and upper neurons (cerebrum, brain stem, etc.)
    • Connections between upper and lower can be pyramidal or extrapyramidal
  201. sensory system
    transforms physical energy into neural information
  202. Upper motor neurons of the motor system
    • efferent neurons in he cerebrum and brains stem.  Decend to brain stem and spinal cord. 
    • Exitation or inhibition of lower motor neurons
  203. Pyramidal system (corticospiral)
    direct connection (upper and lower motor neurons) in PRIMATES.  precise movement of manus and pes, lips and tongue. 
  204. Extrapyramidal system
    • all non-pyramidal voluntary movement motor tracts.  Cerebral cortex.  DOMESTIC ANIMALS (coarse movements) Not corticospinal. 
    • (vestibulospinal, tectospinal, reticospinal, rubrospinal (carnivores and ungulates))
  205. Rubrospinal tracts
    • motor extrapyramidal system tract that involve NONPRIMATE voluntary and skilled movements
    • Red nucleus (cerebral cortex initiates)
  206. Lower motor neurons
    • cell bodies inthe brain stem or spinal cord grey matter.  Travel in the PNS cranial and spinal nerves
    • Take impulses from UMN to effector
  207. Vestibulospinal tract and reticulospinal tract
    subconscious maintinence of an upright and balanced position in Earth's gravity
  208. UMN damage vs LMN damage
    • UMN: gait ataxic, paresis or plegia, normal to increased reflexes and muscle tone, slow atrophy
    • LMN: gait ataxia, paresis or plegia, decreased to absent reflexes and muscle tone, rapid atrophy
  209. Motor cortex
    • 3 parts: primary (discrete muscle movement), supplementary (sequences), premotor (orientation of the body). 
    • Frontal lobe.  More rostral in domesic animals than humans. 
  210. Basal nuclei and muscle movement
    • do not initiate but modify muscle movement.  Input from motor and cerebral cortex and project back through the thalamus. 
    • Select appropriate movement patterns and suppress inappropriate (antagonistic) patterns
  211. cerebellum and muscle movement
    compare information about movement plan with actual mocement--the double-checker. 
  212. What was wrong with Spike?  rear limb weakness in pelvic limbs followed by forelimb weakness and quadriparalysis (was hunting a week ago)
    Tick-bourne illness, neurotoxin understimulating the system.  Interferes with ACH release, presents 5-9 days after tick attaches.  Moves up the body--pelvic limbs to fore, to paralysis, to respiratory issues.  Can go into face.  Can feel pain without being able to move.  Eventually lose respiratory function.  Remove the tick to treat--only some female ticks.