Human beings have five basic senses touch hearing smell taste and sight Different parts of the body send information to the brain about each of those senses For sight it is the eyes that do this work Sight allows us to learn about the world around us and to interact with objects and people WHY DO WE HAVE EYES The eye is the organ that gives animals the ability to see 4
Humans have two eyes that face forward from the face This allows us to see what is directly in front of us Some animals have eyes on either side of the head This is helpful for those that are often hunted such as rabbits With the eyes far apart they can watch for danger from many directions Think about the five senses Is one more important than the others What would life be like without one of your senses THINK ABOUT IT These students are using their eyes to read text on their tablets 5
Humans have two eyes Each eye looks like a ball with a stem The eyeball sits in a socket or opening in the skull The skull bone protects the eye The front of the eye sticks out a bit It is protected by an eyelid When the eyelid closes tears move across the eye to moisten and wash it Eyelashes help as well EYE STRUCTURE 6
They act like screens on a window to keep dust and small specks of dirt out of the eyes Eyes are filled with a clear jellylike substance which is surrounded by three layers Each of these layers called coats contains several important parts of the eye Tears clear out irritations like those caused by the oil released from chopped onions Eyelids and eyelashes protect the eye Humans blink their eyes every three or four seconds on average What does it feel like when you don’t blink for a long time THINK ABOUT IT 7
