Which type of light receptor cell helps distinguish detail in bright light?

• A. Rods
• B. Cones
• C. Ganglion cells
• D. Bipolar cells

Answer: (B)

Cones are the light receptor cells that support high-resolution, color vision in bright conditions. They have small receptive fields and are densely packed in the fovea, which lets the brain distinguish fine detail when lighting is good. Rods, by contrast, are more sensitive in dim light but have larger receptive fields, so they provide less detail and don’t convey color in bright light; they can even saturate when it’s well lit. The other retinal cells, bipolar and ganglion, aren’t light detectors themselves—they relay and process signals from photoreceptors to the brain.