Rods And Cones Lab Report

The retina is a layer of tissue in the back of the eyeball that contains photoreceptors. These photoreceptors are called rods and cones. They are both sensitive to light and convert the light into signals that the brain can read. Rods interpret low intensity light, while high intensity light is interpreted by cones. Rods cannot convey color, but cones can.
Rods are located around the outside of the retina. Rods come into affect with periphery vision. Therefore, when light is dim, rods are the primary photoreceptors causing the periphery vision to have the best resolution. In this dim light, the brain sees images in black and white. Cones are distributed more around the center of the retina, around the fovea centralis. The fovea centralis is the area where an image is focused when it is being concentrated on. Cones come into affect during high intensity light and are less sensitive to light than . So when it is bright, the resolution ability is best at the center of one’s vision. Cones send …show more content…
A subject was seated about three feet from a wall. The subject was instructed to focus on a specific spot on the wall during the entire activity. A protractor was held horizontally and perpendicularly against the forehead of the subject. A colored ball attached to a string about two feet long was held to the side of the subject’s head and out of sight at 0 degrees. The other end of the string was attached to the middle of the protractor. The subject was unaware of the color of the ball. The colored ball was then slowly moved into the sight of the subject while the subject was still focusing on the spot on the wall. The subject was instructed to inform the others when they could first see the ball, then again when they could tell what color the ball was. This process was repeated 3 more times. The field of vision was then calculated, assuming the peripheral vision was the same for both