The Eye

• What are the structures in the eye responsible for?

  They are sensitive to light and responsible for sight.
• What is the function of the cornea in the eye?

  The cornea reflects (focuses) light into the pupil.
• What does the iris control?

  The iris controls how much light enters the pupil.
• How does the lens function in the eye?

  The lens reflects incoming light, making it onto the retina.
• What do the eye muscles do?

  The eye muscles move the eye and are attached to suspensory ligaments.
• What is the role of the ciliary body in the eye?

  The ciliary body works together to alter the shape of the lens.
• What is the retina?

  The retina is the light-sensitive part of the eye covered in receptors called rods and cones.
• What are rods and cones in the retina?

  Rods are sensitive to dim light, while cones are sensitive to different colors.
• What is the function of the optic nerve?

  The optic nerve carries impulses from the receptors to the brain.
• How does the lens focus on distant objects?

  The ciliary muscles relax, allowing the suspensory ligaments to pull the lens into a less rounded shape.
• How does the lens focus on near objects?

  The ciliary muscles contract, making the suspensory ligaments slack, so the lens becomes more rounded.
• What is long-sightedness?

  Long-sighted people are unable to focus on near objects.
• What are the main components of the eye and their functions?

  • Cornea: Reflects light into the pupil
  • Iris: Controls light entering the pupil
  • Lens: Reflects light onto the retina
  • Eye muscles: Move the eye and are attached to suspensory ligaments
  • Ciliary body: Alters the shape of the lens
  • Retina: Light-sensitive part with rods and cones
  • Optic nerve: Carries impulses to the brain
• How does the eye focus on objects at different distances?

  • Distant objects: Ciliary muscles relax, lens flattens
  • Near objects: Ciliary muscles contract, lens becomes rounder
• What are the characteristics of rods and cones?

  • Rods: Sensitive to dim light, not good for color
  • Cones: Sensitive to colors, not good in dim light