Describe the relationship between the structure of the eye and sight OBJECTIVE: Describe the relationship between the structure of the eye and sight

What you will learn: You will be able: - to identify, label, and describe the retina, optic nerve, lens, cornea, iris, pupil and sclera. explain what type of lens the eye contains. Diagram how images are taken in by the eye and how the brain translates the images.

Review: Concave and Convex Lenses How does a Concave lens work? How does a Convex lens work? Name objects that use these types of lenses. What do we have as a human that is a lens? EYE

Sclera The tough white protective tissue that covers the entire eyeball except for the cornea. The “white” of the eye.

Cornea the hard transparent circular area on the front of the eyeball that allows rays of light to enter the eye, and which helps focus the light on the retina.

Iris the colored part of the eye that surrounds the pupil. The size of the iris changes to allow more or less light through the pupil.

Pupil The opening in the iris through which light enters the eye. The amount of light that enters the eye. Experiment: Pupil dilation Students get partner and examine each other’s pupil Turn lights off for 20 seconds Turn lights on and have parner re-examine pupil Discuss results

Lens a small transparent structure behind the pupil of the eye that helps focus light rays on the retina.

Retina Layers of nerve cells, including cones and rods, which cover the rear half of the eyeball. -Rod cells- enable us to see in dim light, but only in black, white and grays, not in color. -Cone cells- respond to color and detect fine details.

Optic Nerve The nerve that carries information from the eye’s retina into the brain.

What do we know about convex lens. What do they do to objects What do we know about convex lens? What do they do to objects? How Does the Brain work to translate these images?

Seeing with Your Brain Several parts of the rear of the brain are involved in making sense of the information from your eyes. providing color form motion and whatever else is involved in what you are looking at.

Better Than a Camera? Camera shutter- controls the amount coming in. lens- moved to focus film- when film is developed it corrects the upside down image. Eye iris- adjusts to let light in. lens- focus images on retina brain- flips images right side up

Question Time A convex lens projects an image that is upside down. If the image on your retina is upside down, why doesn’t the world look upside down to you? Lights on, lights off experiment. How did your pupils respond and why?

What are the cell types found in the retina What are the cell types found in the retina? What message do they send to the brain? What type of corrective wear can be worn by both near and far sighted people?

Describe the relationship between the structure of the eye and sight OBJECTIVE: Describe the relationship between the structure of the eye and sight

What you learned: You should be able: - to identify, label, and describe the retina, optic nerve, lens, cornea, iris, pupil and sclera. explain what type of lens the eye contains. Diagram how images are taken in by the eye and how the brain translates the images.

WRAP UP 1. DO YOU HAVE ANY QUESTIONS? 2. DO YOU HAVE ANY SUGGESTIONS ON MAKING THIS A MORE EFFECTIVE PRESENTATION?

FOLLOW UP ACTIVITY ***DRAW THE EYE ***LABEL ITS PARTS ***EXPLAIN OR DESCRIBE EACH PART’S RESPONSIBLITY

THE EYE