eyes

    Cards (23)

    • What is the sclera
      tough supporting wall of the eye
    • what is the cornea
      transparent outer layer that refracts light into eye
    • The iris contains muscles that allow it to control pupil diameter
    • the pupil controls how much light enters the eye
    • what part of the eye focuses light onto the retina
      the lens
    • what ligament controls shape of lens
      suspensory ligaments
    • where does the optic nerve carry impulses from to the brain
      retina
    • what happens when light receptors detect a bright light
      a reflex is triggered that makes the pupil smaller
    • what happens to muscles when the pupil shrinks
      ciliary muscles contract radial muscles relax
    • what happens to muscles when pupil widens
      ciliary muscles relax radial muscles contract
    • what is it called when the eye focuses light on the retina by changing the shape of the lens
      accommodation
    • looking at near objects
      ciliary muscles contract suspensory ligaments relax and lens becomes fat (increasing amount of light refracted)
    • looking at distant objects
      ciliary muscles relax suspensory ligaments contract and lens becomes thin (decreasing amount of light refracted)
    • short-sightedness
      myopia
    • long-sightedness
      hyperopia
    • hyperopia means objects are brought into focus

      behind the retina
    • myopia means objects are brought into focus

      in front of the retina
    • hyperopia is corrected with
      convex lenses
    • myopia is corrected with
      concave lenses
    • name three treatments for vision defects
      contact lenses
      laser eye surgery
      replacement lens surgery
    • contact lenses are convenient but have a higher risk of eye infection
    • laser eye surgery has a risk of infection and complications
    • replacement lens surgery has a higher risk than laser eye surgery and can possibly damage the retina leading to blindness