Zusammenfassung der Ressource
Structure of the Eye and Retina
- Pupil- center of the
iris (coloured area) in
which light enters
through and opening in
the centre and is
projected on the back
of the eye.
- Lens- focuses
the pupil, is
adjustable
- Cornea-
focus the
pupil, is not
adjustable
- Retina- where the light is
projected at the rear surface of
the eye. Is lined with visual
receptors.
- Light always strikes
the opposing side
- Fovea- the pit at the back
of the eye that is specialised
for acute, detailed vision.
- Almost absent of blood
vessels and ganglion
cells creating
unimpeded vision.
- Rods- respond to
faint light and are not
useful in daylight.
Bright light bleaches
them. Abundant in
the periphery of the
human retina.
- Cones- less active
in dim light and are
essential in colour
vision. Abundant in
and near the fovea.
- Red-
longwave
700nm
- Green-
medium
wave
500nm
- Blue-
shortwave
350nm
- Ganglion cells- recieves
messages from bipolar
cells (rods and cones)
and the ganglion cells
join together (close to
the center of the eye)
and travel to the brain.
- Blind spot- the
ganglion cells form the
optic nerve. The point in
which it leaves the eye
is a blind spot as there
are no receptors.