A&P Chapter 17 - Special Senses - EYE

  1. orbital cavity
    • fat and bone that surrounds eye
    • maxilla, ethmoid, lacrimal, frontal, temporal bones
  2. palpebrae
    eyelids and eyelashes
  3. meibomian gland
    oil gland that lubricates eyelids to keep them from sticking together
  4. tarsal plate
    band of connective tissue that shapes eyelid
  5. conjunctiva
    mucous membrane that lines and moistens inner eyelid
  6. lacrimal apparatus
    • lacrimal gland and tubes
    • produces tears
  7. extrinsic eye muscles
    fastest muscles in the eye
  8. superior rectus
    eye muscle that moves eye up
  9. inferior rectus
    eye muscle that moves eye down
  10. lateral rectus
    eye muscle that moves eye out
  11. medial rectus
    eye muscle that moves eye in
  12. superior oblique
    eye muscle that moves eye down and out
  13. inferior oblique
    eye muscle that moves eye up and out
  14. tunics
    layers of the eye
  15. fibrous tunic
    • first layer
    • cornea and clera
  16. cornea
    avascular transparent front of the eye
  17. sclera
    posterior white of the eye
  18. uvea tunic
    • aka vascular tunic
    • middle layer
  19. ciliary body
    • thick ring of muscle that circles lens along with suspensory ligaments
    • helps change shape of lens during accomodation
  20. iris
    • colored part of the eye
    • only brown pigment
  21. pupil
    opening in middle of iris that lets light in
  22. choroid
    • black membrane that surround inner posterior eye
    • prevents light from scattering
  23. tapetum lucidem
    greenish blue region in animals only that allows them to see clearly but not in color
  24. nervous tunic
    • aka retina
    • yellow membrane in front of choroid
    • most light sensitive part of eye
    • several different cells: photoreceptors, ganglion cells, horizontal cells, bipolar cells
    • 2 layers: inner and outer
  25. photoreceptors
    rods and cones that allow us to see light
  26. ganglion cells
    conduct APs
  27. horizontal and bipolar cells
    see shapes and patterns
  28. outer retina
    contains vitamin A and photopigment
  29. inner retina
    contains photoreceptors
  30. rods
    • dim light receptors
    • night vision
  31. cones
    • bright light receptors
    • day vision and color
  32. macula lutea
    • center of retina
    • mostly cones
  33. central fovea
    • center of macula
    • only cones
    • region of clearest and sharpest vision
  34. optic disc
    • lateral to central fovea
    • blind spot
    • no rods or cones
  35. lens
    • avascular protein structure
    • M&M shaped
    • changes shape, causing image to be focused at focal point (directly on the retina)
    • can get cloudy (cataracts)
  36. anterior eye cavity
    between cornea and lens
  37. anterior chamber
    • part of anterior eye cavity
    • between cornea and iris
  38. posterior chamber
    • part of anterior eye cavity
    • between iris and lens
  39. aqueous humor
    • watery liquid that fills entire anterior cavity
    • produced by ciliary muscle
    • maintains pressure inside eye
    • drains through canal of schallen at junction of cornea and sclera
  40. glaucoma
    condition where aqueous humor is not properly drained/pressure builds
  41. posterior eye cavity
    between lens and retina
  42. vitreous humor
    • fills posterior cavity
    • holds retina tight against choroid
    • maintains pressure in the eye
    • supports the lens
    • bends light
  43. imagine formation on the retina
    • light passes through several regions to reach the retina and eventually the brain:
    • cornea
    • aqueous humor
    • iris/pupil
    • photoreceptors
    • bipolar/horizontal cells
    • ganglion cells
    • retina
    • optic disc
    • optic nerve
    • brain stem
    • thalamus
    • occipital lobe
  44. focal point
    • determined by the shape and length of the eyeball
    • light bends and refracts to hight the retina at the focal point
    • if focal point is in front or behind retina, glasses are needed
    • image is upside down and backwards - corrected in occipital lobe
  45. accomodation
    • required to properly focus
    • distant vision: ciliary muscle relaxes, suspensory ligaments contract, lens flattens, pupils dilate, eyes diverge
    • close vision: ciliary muscle contracts, suspensory ligaments relax, pupils constrict, eyes converge
  46. emmetropia
    20/20 vision
  47. presbyopia
    • old sightedness
    • lens loses elasticity and has trouble with accomodation
  48. myopia
    • near sightedness
    • focal point in front of retina
  49. hyperopia
    • far sightedness
    • focal point behind retina
  50. astigmatism
    • irregular curve of the cornea or the lens
    • causes blurred vision
    • 80% of the population
  51. color blindness
    • inability to see certain colors
    • usually red and green
    • men more than women
    • 20% of the population
  52. photopigment
    • colored protein that will change its shape in response to light
    • conducts APs
  53. rhodopsin
    • rods
    • most common photopigment
    • dim light
    • contains retinal and opsin
    • bright light: trans-retinal and opsin do not bind, rhodopsin not produced
    • dim light: trans-retinal bends along 11th carbon, binds with opsin, rhodopsin produced
    • moving from dim to bright straightens retinal (photopigment bleached)
  54. retinal
    vitamin A
  55. opsin
  56. retinal isomerase
    enzyme that helps bending of retinal
Card Set
A&P Chapter 17 - Special Senses - EYE
A&P Chapter 17 - Special Senses - EYE