Eyes

  • All the different parts of your eyes work together to help you see
  • First, light passes through the cornea (the clear front layer of the eye). The cornea is shaped like a dome and bends light to help the eye focus.
  • Some of this enters the eye through an opening called the pupil. The iris (the coloured part of the eye) controls how much light the pupil lets in.
  • Next, light passes through the lens (a clear inner part of the eye). The lens works together with the cornea to focus light correctly on the retina.
  • When light hits the retina (a light-sensitive layer of tissue at the back of the eye), special cells called photoreceptors turn the light into electric signals.
  • These electrical signals travel from the retina through the optic nerve to the brain. Then the brain turns the signal into the images you see.
  • Your eyes also need tears to work correctly.

Keywords

  • Iris - coloured circle around the pupil. It controls the size of the pupil.
  • Pupil - black part of the eye. This is an opening that lets the light in.
  • Lens - this focuses the light on the retina.
  • Retina - the light-sensitive layer at the back of the eye. It is made up of rods and cones.
  • Rods - sense cells that help us see the shape of things.
  • Cones - sense cells that help us see colours.
  • Optic nerve - carries messages from the retina to the brain. The brain turns these into an image of what we are looking at.