Vision and hearing

  1. 3 Coats or Tunics:
    1. Outter most fiberous layer (whites of eyes) serves as the point of attachment for ectrinsic muscles of the eye.
    2. middle vasular layer
    3. inner most later od specialized photoreceptors( rods and cones)
    • Sclera
    • Choroid
    • Retina
  2. Filled with aqueous humor compriesd of anterior and posterior chambers in front of and behind the lend glaucoma canal of schlemm drains aqueuous humor
    anterior cavity
  3. filled with vitreous humor
    vitreous cavity
  4. transparent outer portion sclera covers entier outer wall of eyeball except at cornea
  5. colored portion of eyeball regulates size of pupil
  6. anterior prtion of vascular tunic ciliary miscles change the shape of the lenfs while the ciliary processes secrete aquesous humor
    ciliary body
  7. site where opitc nerve leave eyeball blind spot no rods or cones
    optic disc
  8. 120million/eye allow vision in dim light more numerous in periphery of retina
  9. 6-7 million/eye produce color stimiulated by bright light mroe numerous in center of eye
  10. small depression in center of the retina contains only cones area of highest visual acutiy
    central fovea
  11. bending of light rays occurs at the surface of the cornea and at the surface of the lens
  12. consists of pinna external auditory meatus and tympanic membrane
    external ear
  13. consists of the auditory ossicles (malleus-hammer, incus-anvil, staples-stirrup) oval window, round window, tnedor tympani stapedius
    middle ear
  14. outer bony labyrinth encloses inner mombranous labyrinth
    inner ear
  15. composed of semicirular canals (dynamic equilibrium) vestibule (static equilibrium) cochlea (hearing)
    bony Labyrinth
  16. Bony labyrinth contains____
  17. Membranous Labyrinth is a series of sacs & tubes within the bony labyrinth it contains ____
  18. Physiology of Hearing
    • 1Auricle directs sound waves into external auditory canal
    • 2}Sound waves cause eardrum to vibrate
    • 3}Vibrations transmitted to auditory ossicles
    • {4}Stapes causes oval window to vibrate
    • {5}Oval window movement causes pressure waves in perilymph of scala vestibuli
    • {6}Pressure waves transmitted to scala tympani; excess waves leave via the round
    • window
  19. Physiology of hearing 2
    • 7}Pressure waves from scala vestibuli & scala tympani push on vestibular membrane, thus
    • creating pressure waves in the endolymph of the cochlear duct
    • 8} Endolymphpressure waves cause basilar membrane to vibrate, moving the hair cells of the
    • spiral organ against the tectorial membrane
    • {9}Bending of hair cell stereocilia produces receptor potentials leading to
    • nerve impulse generation
  20. Macula: found in saccule (___ plane) and utricle (____ plane) organ of static equilibrium
    • verticle
    • horizontal
Card Set
Vision and hearing
2nd exam