Cone cells

Cone cells

Cone cells, or cones, are one of the two types of photoreceptor cells that are in the retina of the eye which are responsible for color vision. They are also one of the three types of photoreceptor cells in the retina that are responsible for daylight vision.

Pronunciation

/kəʊn sɛlz/

Etymology

The term "cone cells" is derived from their cone-like shape.

Function

Cone cells are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color. They are also able to perceive finer detail and more rapid changes in images, because their response times to stimuli are faster than those of rods. Cone cells are densely packed in the fovea centralis, a 0.3 mm diameter rod-free area with very thin, densely packed cones which quickly reduce in number towards the periphery of the retina.

Types

There are three types of cone cells, each containing a different type of photosensitive pigment, which are activated when they absorb light. The three types of cones are L-cones, M-cones and S-cones that respond preferentially to light of long wavelengths, medium wavelengths, and short wavelengths respectively.

Related terms

• Photoreceptor cell
• Retina
• Eye
• Rod cell
• Fovea centralis
• Photosensitive pigment
• L-cones
• M-cones
• S-cones

External links

• Medical encyclopedia article on Cone cells
• Wikipedia's article - Cone cells

This WikiMD dictionary article is a stub. You can help make it a full article.

---

Languages: - East Asian 中文, 日本, 한국어, South Asian हिन्दी, Urdu, বাংলা, తెలుగు, தமிழ், ಕನ್ನಡ,
Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, European español, Deutsch, français, русский, português do Brasil, Italian, polski