LC Biology eye

  1. Describe the sclera and its function
    The white part of the eye. (opaque and tough)

    function: shape and protection
  2. Describe the cornea and its function.
    The transparent part of the sclera at the front of the eye.

    Let's light in and bends it towards the retina
  3. Describe the Conjunctiva and its function
    Transparent membrane protecting the cornea
  4. Describe the Choroid and its functions
    contains the blood capillaries to nourish the eye and melanin (black pigment) to absorb light (no internal reflection of light)
  5. Describe the retina and its function
    the innermost layer containing the light receptors (rods and cones)
  6. Describe the rods
    contain rhodopsin (vitamin A required to form it)

    detect black and white

    work in dim light

    found all over retina
  7. Describe the cones
    Have 3 pigments that detect blue, red and green

    detect color

    found mostly in the fovea

    work in bright light
  8. Blindspot
    the area where the optic nerve leaves the eyeball

    contains no visual receptors
  9. Fovea (yellow spot)
    opposite the centre of the pupil

    contains cones only. Regions of sharpest vision, most images are formed here
  10. Optic nerve
    Carries impulses from the retina to the brain.
  11. Iris
    coloured part of the eye. Controls size of pupil and amount of light entering the eye (reflex action).

    Its circular muscle contract to narrow the pupil in bright light to reduce the amount of light and its radical muscles contact to widen the pupil in dim light enters the eye
  12. Pupil
    opening in the iris through which light enters.
  13. Lens
    biconvex, transparent and elastic, changes shape to focus light on to the retina. Contains a clear protein which can become cloudy (cataracts).
  14. Ciliary muscle
    changes shape of the lens
  15. Suspensory ligament
    Attaches the ciliary body to the lens.
  16. Aqueous humor
    A watery liquid between cornea and lens, made in ciliary body-maintains eye shape; nourishes cornea and lens (these don't have their own blood supply) and helps to refract light.
  17. Vitreous humor
    A jelly-like substance between lens retina, gives shape to the eye
  18. Accommodation
    changing the shape of the lens to focus near and distant objects
Card Set
LC Biology eye
questions on the senses