How do rods detect light

To learn more about cones and rods, we have to zoom in on one of the most important parts of the eye, the retina. Cones and rods are two types of photoreceptors within the retina.

This means that they are responsible for receiving signals or images , processing them, and sending them to the brain. The rod is more sensitive than the cone. Slowly move your head closer to the image. At a certain distance, the blue line will not look broken! Did you know? Why can't you see very well when you first go into a darkened room like a movie theater? When you first enter the movie theater, the cones in your retina are working and the rods are not yet activated.

Cones need a lot of light to work properly; rods need less light to work, but they need about minutes to take over for the cones. After minutes in the dark, the rods do work, but you cannot see colors very well because the rods do not provide any color information. The cones, which do provide color information, need more light, but do not work well in the dark.

After the movie is over and you leave the theater, everything looks very bright and it is hard to see for a minute or two. This is because the rods become "saturated" and stop working in these bright conditions. It takes a few minutes for the cones to begin to function again, and for normal vision to be restored.

A complete lesson plan on the eye and its connections - teacher and student guides available. Also, try some experiments to test your sense of sight and take a short, interactive quiz about the eye and sight. Find out more about blind spots , vision , the retina and photoreceptors. The Retina The retina is the back part of the eye that contains the cells that respond to light. Stare at the "g" in the word "light" in middle of the following sentence: "Your vision is best when light falls on the fovea.

To find your blind spot, look at the image below or draw it on a piece of paper: Close your left eye. Let's take a minute to talk about vitamins.

The pigment molecule attached to the proteins in photoreceptors is called retinal. When retinal absorbs photons, it gets destroyed in the process.

In order to regenerate more retinal, your body needs Vitamin A. Carrots are one food that is high in Vitamin A. This makes them good for your eyes, but don't think they will make your eyesight better.

While carrots are good for the health of your eyes, they won't make you see better or let you ditch your glasses or stop wearing your contact lenses. Eye anatomy illustration from Beginning Psychology v. Labels modified for this page. CJ Kazilek, Kim Cooper. Rods and Cones. If you look toward the center there are few blue sensitive cones. Human Eye Worksheet. By volunteering, or simply sending us feedback on the site. Scientists, teachers, writers, illustrators, and translators are all important to the program.

If you are interested in helping with the website we have a Volunteers page to get the process started. Digging Deeper. Digging Deeper: Depression and the Past. Digging Deeper: Germs and Disease. Digging Deeper: Milk and Immunity. How Do We See? How Do We Sense Smell? How Do We Sense Taste? How Do We Sense Touch? What is Evolutionary Medicine? What's a Biologist? What's a GMO? What's a Genome? Nucleus: where DNA stays in the cell, plural is nuclei. Rods and Cones of the Human Eye The anatomy of the human eye.

Click to enlarge and for more information. Cell orientation makes it easier to recycle parts. Image by HuBoro. View Citation You may need to edit author's name to meet the style formats, which are in most cases "Last name, First name.