http://www.ck12.org Chapter 5. Energy
FIGURE 5.140
Summary
- The human eye is an organ that is specialized to collect light and focus images. Light enters through trans-
parent structures at the front of the eye. It is focused by the cornea and lens on the retina at the back of the
eye. - The ability to see is called vision. The brain and eyes work together to allow us to see. The eyes collect and
focus visible light and change it to electrical signals that travel to the brain. The brain interprets the signals
and “tells” us what we are seeing.
Vocabulary
- vision: Ability to sense visible light and see.
Explore More
At the following URL, experiment with color vision using the simulation. Then fill in the blanks in the sentences
below. http://phet.colorado.edu/en/simulation/color-vision
Single-Bulb Simulation:
- If the bulb is white and the filter is green, the person sees __.
- If the bulb is green and the filter is green, the person sees __.
- If the bulb is green and the filter is blue, the person sees __.
Red-Green-Blue Bulbs Simulation:
- If all three bulbs are set a full intensity, the person sees __.
- If red and green bulbs are set at full intensity but the blue bulb is off, the person sees __.
- If blue and green bulbs are set at full intensity but the red bulb is off, the person sees __.
Review
- Create a flowchart to summarize how the eye gathers and focuses light.