Rods

Definition

Rods are photoreceptor cells in the retina responsible for vision in low light conditions. They are highly sensitive to light but do not detect color.

5 Must Know Facts For Your Next Test

1. Rods are more numerous than cones in the human retina, with approximately 120 million rods.
2. They are primarily located around the periphery of the retina.
3. Rods contain a photopigment called rhodopsin, which is sensitive to dim light.
4. They provide high sensitivity to light but low spatial resolution and no color vision.
5. Rods play a crucial role in night vision and peripheral vision.

Review Questions

• What type of photopigment is found in rods?
• How do rods differ from cones in terms of location and function?
• Why are rods important for night vision?

Related terms

Cones: Photoreceptor cells responsible for color vision and visual acuity under bright light conditions.

Retina: The light-sensitive layer at the back of the eye, containing rods and cones.

Rhodopsin: A photopigment found in rods that is sensitive to low levels of light.