Neuro Exam 1.3

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Neuro Exam 1.3
2013-01-29 16:50:47
neurology anatomy

review of lecture 3 for neuro exam 1
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  1. Neurons:
    a type of nervous system cell
  2. Are neurons capable of conducting an impulse?
  3. Neurons conduct impulses in the form of what?
    action potentials
  4. What other cells can produce action potentials?
    skeletal muscles
  5. How many neurons are in the body?
    100 billion
  6. Neurons are heterogenous:
    take many different forms, but basically function the same
  7. What is a soma?
    cell body of a neuron
  8. Describe the cell body of a neuron:
    • fairly large (4-135 microns in diameter)
    • shape varies (heterogenous)
    • contents are similar to that of other cells in the body
  9. What are the characteristics of the cell body/neuronal cell of a neuron?
    • nucleus
    • non-nuclear structures (cellular organelles)
    • mitochondria (power house)
    • lysosomes
    • rough endoplasmic reticulum
    • smooth endoplasmic reticulum
    • golgi apparatus (golgi body)
    • cytoskeleton
  10. nucleus:
    middle of cell body
  11. If the nucleus is not in the middle of the cell body, the cell is considered:
  12. Is the nucleus large or small?
  13. What is the shape of the nucleus?
  14. The nucleus has a nuclear membrane (envelope) with a distinct:
    double layer
  15. What allow for passage of large macromolecules back and forth w/ cytoplasm through the nuclear membrane of a neuron?
    nuclear pores
  16. What is the nuclear membrane continuous w/?
    endoplasmic reticulum
  17. What is contained in the nucleus?
    46 chromosomes and DNA
  18. Where does DNA undergo transcription for mRNA?
    in the nuclues
  19. Where does translation occur?
    rough ER in cytosol
  20. Where does protein synthesis occur?
    rough ER in cytosol
  21. Nucleolus:
    large inclusion w/in the nucleus where ribosomal RNA is synthesized and produced
  22. What is rRNA involved w/ and where?
    involved w/ protein synthesis at ribosome
  23. Non-nuclear structures (cellular organelles):
    can malfunction in neurons
  24. What is the power house of a neuron?
  25. Where are mitochondria found?
    in the cytoplasm scattered throughout cell body
  26. What are mitochondria involved with?
    engergy production (ADP -> ATP)
  27. What can neurons use for energy?
    only glucose or glucose products (will not utilize fats or amino acids to make energy)
  28. What chemical does the mitochondria require?
  29. Can neurons store glycogen?
    • no, but skeletal muscle can
    • once energy supply is gone, there is no more energy (unconsciousness)
  30. What is utilized during cellular respiration?
  31. Lysosomes:
    double membrane-bound vesicles that contain hydrolytic enzymes (50 or more)
  32. What is the function of lysosomes?
    digest things w/in cell [substances that orignate in and out of cell]
  33. What are two ways that lysosomes can do to cause cell death?
    • necrosis
    • apoptosis
  34. Necrosis:
    lysosomes rupture and digest contents of cell (self-digesting)
  35. apoptosis:
    • pre-programmed cell breakdown (natural prosses in which cells are programmed to die off)
    • genetically determined cellular self-destruction process
  36. What is another name for Rough Endoplasmic reticulum?
    nissl substance
  37. What is the rough endoplasmic reticulum?
    • a bunch of ribosomes
    • flattened, double-layered membrane structures lined w/ ribosomes giving it rough appearance
    • very active part of cytoplasm
  38. Where is the rough endoplasmic reticulum located?
    cell body and dendrites (close to nucleus)
  39. What occurs in the rough ER?
    Translation and synthesis
  40. What general proteins are involved with translation and synthesis of the rough ER?
    enzymes: hundreds needed for cells to work
  41. What structural components are involved with translation and synthesis in the rough ER?
    • actin
    • tubulin
    • neurofilaments
    • microfilaments
  42. What other proteins are involved in translation and synthesis in the rough ER?
    • plasma membrane proteins
    • neuro-transmitters and neuro-modulators
  43. The rough ER is the site of:
    protein synthesis
  44. The smooth ER is a continuation of:
    rough ER
  45. Does the smooth ER contain ribosomes?
    no, therefore, it is smooth
  46. What is the function of the smooth ER?
    to channel proteins produced in the Rough ER to the golgi apparatus
  47. What is another name for golgi apparatus?
    golgi body
  48. What is the golgi apparatus?
    double-membrane, flattened channels (sometimes a sac-like appearance)
  49. What is the function of the golgi apparatus?
    • receive products (protein molecules) from smooth ER
    • modify, sort, and package protein molecules into specific membrane-enclosed vesicles
    • then migrate to where they are needed
  50. The packaged protein molecules from the golgi apparatus can go to:
    • cell membrane regions for growth (contains growth protein)
    • lysosome (contains hydrolytic enzyme)
    • forms neuro tubular to be transported elsewhere
  51. What normally causes diseased w/ golgi apparatus?
  52. Review:
    Nucleus (DNA) -> cytosol (cytoplasm) -> rough ER -> smooth ER -> golgi apparatus ->
    cell membrane regions, lysosomes, neurotubules, numerous types of vesicles, etc.
  53. What is the function of the cytoskeleton?
    • gives integrity to cells
    • forms shape and gives support to neuron
  54. Is the cytoskeleton an organelle?
  55. Where is the cytoskeleton found?
  56. What 3 fibular organelles (protein molecules) make up the cytoskeleton?
    • microfilaments
    • microtubules
    • neurofilaments
  57. What makes up microfilaments?
    primarily actin (protein molecules) --smalles in diameter
  58. Where is actin found?
    • axoplasm of the neuron in the axon
    • close to cell membrane
    • lots in growth cone
  59. How many microfilaments does each neuron have?
    they are in constant flux (some days you have more, some less) due to inconsistencies in the size of the cell bodies
  60. When there is less actin, does this change the form of the cell?
    less actin causes cell shape to be smaller, but the basic form is still there
  61. Growth cone production:
    as dendrites grow throughout development, so neuron can get from point a->b
  62. What is another name for microtubules?
  63. What are microtubules?
    • fibular organelle that makes the cytoskeleton
    • long tubular structures that form tracts to transport metabolites, vesicles, and ions
  64. Tubulin:
    • found in microtubules
    • molecule proteins, largest of the 3 fibrillar proteins (25nm in diameter)
  65. Where are microtubules located?
    cytoplasm, axon, and dendrites
  66. What are microtubules very important to?
    axonal transport mechanism
  67. What is another name for neurofilaments?
  68. What is the most abundant of fibrillar proteins?
  69. Where are neurofilaments found?
    • cytoplasm
    • in axons-neurofilament protein
    • oriented along the axis of the axon (run parallel)
  70. What is the function of neurofilaments?
    add strength (resiliency) and diameter (caliber) to axon
  71. What is the diameter of a neurofilament?
  72. When neurofilaments are defected, they cause what disease?
  73. Microscopically, neurofilaments are seen as clumps in cells of which parts of the brain?
    • frontal lobe
    • hippocampus
  74. What is the Axonal Transport System?
    transportation of substances from cell body to cellular processes and conversely utilizing microtubules
  75. What are the two directions that the axonal transport system can take?
    • anterograde
    • retrograde
  76. What is another name for anterograde?
  77. Anterograde:
    transport away from cell body to the cellular processes (efferent)
  78. Retrograde:
    transport from cellular process towards cell body (afferent)
  79. What are the two rates that the axonal transport system work at?
    • fast
    • slow
  80. Fast axonal transport system:
    • 200-400mm per day
    • both anterograde and retrograde (16in/day)
  81. Slow axonal transport system:
    • 1-5 mm per day
    • only in anterograde
  82. What movement direction and speed combonations are found in the axonal transport system?
    • fast anterograde
    • fast retrograde
    • slow anterograde
    • NO slow retrograde...
  83. What molecules travel the axonal transport system during fast anterograde?
    • plasma membrane components
    • smooth ER
    • synaptic vesicles containing neurotransmitter
    • mitochondria
  84. What molecules travel the axonal transport system during fast retrograde?
    • mitochondria
    • degenerated structures
    • vesicles and molecules: nerve growth factor and other trophic molecules
  85. What molecules travel the axonal transport system during slow anterograde?
    • soluble enzymes
    • proteins for regeneration
    • proteins to renew cytoskeleton and plasma membranes (actin)
  86. What are force-generating motor proteins?
    • drives axonal transport system
    • how material is transported along neurotubules
  87. What are the two categories of force-generating motor proteins?
    • kinesin
    • dynein
  88. kinesin:
    protein molecule for anterograde movement
  89. dynein:
    protein molecule for retrograde moement
  90. What is the energy source for the force-generating motor proteins?
  91. How do the force generating motor proteins work?
    • bind substance to be transported to neurotubule
    • neurotubule acts as a guide through the axon
  92. What are the 3 options for movement of the force-generating proteins in the axonal transport system?
    • 1. can pass another vesicle moving in the same direction on the same neurotubule
    • 2. two vesicles can move bi-directional (opposite directions) on the same neurotubule
    • 3. vesicles can shift b/w adjacent neurotubules