The Eye

• Label the diagram

  The eye

  A) suspensory ligament

  B) sclera

  C) Retina

  D) Fovea

  E) Optic nerve

  F) Lens

  G) Pupil

  H) Conjunctiva

  I) Cornea

  J) Iris

  K) Ciliary muscle

  
• Label the diagram

  The eye

  A) Aqueous humour

  B) Vitreous humour

  C) sclera

  D) Choroid

  E) Retina

  F) Fovea

  G) Optic nerve

  H) Blind spot

  I) Ciliary body

  J) Suspensory ligaments

  K) Iris

  L) Pupil

  M) Cornea

  N) Lens

  
• The eyes are the sense organs that respond to light
• Where are the eyes situated?

  In the eye sockets within the skulls
• What keeps the eyes attached and allows them to move around?

  The eye muscles
• How many layers are in the wall of the eye?

  Three
• What are the layers of the eye?

  These layers are;

  • The Sclera
  • The Choroid
  • The Retina
• What is the sclera?


  The thick, outer layer that protects the eye
• Where is the sclera located?

  In the front of the eye, the sclera is

  continuous with the transparent

  cornea.
• what helps the cornea bend the light rays that enter the eye?

  The shape of the cornea
• The shape of the cornea helps bend the

  light rays that enter the eye so

  that they meet on the back of the eye. (REFRACTS THE LIGHT THE MOST)
• Which layer is the choroid

  The middle layer
• What is the choroid richly supplied with

  Blood vessels
• In the front of the eye, the choroid forms a thick ring of tissue which

  contains the ciliary muscles.
• What is attached to the edge of the ciliary muscles?

  The suspensory ligaments
• What do the suspensory ligaments do?

  Hold the lense in position
• What is the lense?

  The lens is an elastic, transparent body made up of an outer capsule

  and inner jelly-like substance.
• What is the main function of the lens

  Adjust the eye for near and far vision
• What does the choroid also do?


  Helps the cornea in bending the light rays that enter the eye.
• What prevents reflection within the eye?

  The Choroid
• What is the innermost layer of the eye?

  The retina
• What is the retina made up of?

  It is made up mainly of light

  sensitive cells (rods) and

  colour-sensitive cells (cones).
• What do the rods respond to?


  They respond to dim light and give you black and white vision.
• What do the rods not allow you to see?

  They do not allow you to see shapes but rather allow you to be good at noticing movements.
• Where are the rods scattered around


  They are scattered around the retina
• What do the cones respond to?

  They respond to bright light and allow you to see see shapes accurately in colour.
• Where are the cones concentrated?

  They are concentrated near the yellow spot.
• What is the yellow spot?

  The yellow spot is the region of the retina with the sharpest vision.
• What is the blind spot?

  The blind spot is the point of the retina where the nerve fibres leave

  the eye.
• What does the optic nerve transmit to the brain?

  It transmits nerve impulses up to the brain
• What is the yellow spot also called?

  The macula
• Yellow oval spot


  At the center of the retina (back of the eye)
• Macula lutea (fovea)


  • Part of the retina responsible for sharp, detailed central vision
  • Contains a very high concentration of cones (light sensitive cells that give detailed central vision)
• The macula lutea, also called fovea, contains a very high concentration of cones
• Label the diagram

  label the macula

  A) fovea

  B) Retinal arteries and veins

  C) Optic nerve

  D) Macula

  
• What is responsible for vision at low light levels and gives you black-and-white-vision?

  Rods
• What are active at higher light levels and are capable of colour vision?

  Cones
• images are inverted on the way to the retina
• Light passes through


  1. Cornea

  2. Aqueous humour

  3. Pupil

  4. Lens

  5. Vitreous humour

  6. Strikes the photoreceptors (rods & cones) of the retina
• Light


  • Refracted by lens & cornea
  • Small upside down image is formed on the yellow spot