Retinal Cone (Noun)
Meaning
A visual receptor cell in the retina that is sensitive to bright light and to color.
Classification
Nouns denoting body parts.
Examples
- The retina in humans contains over 120 million retinal cones that mediate color vision and function best in relatively bright light.
- Each retinal cone contains the pigment rhodopsin which changes shape when it absorbs light, triggering a signal to the optic nerve.
- Retinal cones are less sensitive to dim light than rods, and are more densely packed in the central part of the retina.
- In the fovea, the part of the retina responsible for sharp central vision, retinal cones are packed tightly together, allowing for high-acuity color vision.
- The three types of retinal cones have different spectral sensitivities, corresponding roughly to red, green, and blue light, and are activated in various combinations to produce the sensation of a wide range of colors.