biology final

  1. Pimary receptors (1 degree)
    recetpres ARE sepcialized ends (generally dendrites) of sensory neurons
  2. Secondary (2nd degree)
    consist of seperate receptor cell (often an epithelial cell) which synapses with afferent neuron
  3. rectpro potentials
    electronically spread to the spike initiating zone where if the depolariztion reaches threshold (generator potential) an AP is generated
  4. What affects the amount of neurotransmitter released
    The size of the graded receptor potential
  5. How does the brain determine stimulas intensity
    • Varioaton in the frequencing of APs delviered to the CNS by a given sonsory receptor
    • Variation in the # of receptors activated
  6. Adaptation
    when some sensory cells respond less when stimulation is held constant and/or repeated
  7. gustation
    • the sense of taste
    • most taste sensors are 2 degree type sensory cells
  8. What are the five tastes
    sweet, bitter, sour, salty, umami
  9. Olfaction
    • the sense of smell
    • First degree sensors
  10. glomeruli
    convergance of axons from the nuerons with the same receptors for olfaction
  11. vomeronasal organ (VNO)
    • in amphibians reptiles and many mammals
    • specilized for pheromones and goes to an accesory olfactory bulb
  12. how do mechanoreceptors work?
    • physical distortion of a mechanorecptor's plasma membrane causes ion channels to open, which leads to the generation of APs
    • Density of tactile receptors influence how finely stimulation can be resolved
  13. muscle spindles
    • where stretch receptors are embedded in vertebrate skeletal muscles
    • they are modified msucle fibers that are innvervated in the center with extenstion of sensory neurons
    • The CNS uses information from msucle spindles to maintain a certain level of contraction or muscle tone
  14. gray matter
    the tissue rich in neuronal cell bodies part of the spinal cord
  15. white matter
    contains the axons of the spinal cord
  16. spinal nerves
    leave the spinal cord at regular intervals; each one ahs two roots, one connecting it ot the dorals horn of the gray matter and the other connecting with the ventral horn
  17. monosynaptic reflex
    the simplest spinal reflex involving only two neurons and one synapse (no brain involvement)
  18. Golgi tendon organ
    • stretch receptor found in tendons and ligaments
    • when a msucle contraction becomes too forceful, the golgi tendon organ sends signals to the CNS that inhibit motor neurons and the msucle relaxes
  19. Pinnaue
    collect sound waves and direct them into the auditory canal, which leads to the middle inner ear
  20. tympanic membrane
    the eardrum
  21. rhodopsins
    molecules used for photosensitivity
  22. rod cell
    • modified neuron that releases neurotransmitters that influence other neurons
    • the outer segment has a stack of discs of plasma membrane densely packed with rhodopsin. this discs function to capture photons
  23. What is the difference between vertebrates and invertebrates response to light?
    • Vertebrates hyperpolarize photoreceptors
    • invertebrates depolarize photoreceptors
Card Set
biology final