What type of photoreceptors dominate the fovea?

• A. Rods, which enable night vision.
• B. Cones, which enable detailed, color-rich perception in bright conditions.
• C. Bipolar cells, which transmit signals from photoreceptors.
• D. Ganglion cells, which send signals to the brain.

Answer: (B)

Cones dominate the fovea because this region is specialized for high-acuity, color vision in bright light. The fovea centralis has an extremely high density of cone photoreceptors and, importantly, virtually no rods, arranged so light primarily stimulates cones with minimal interference from other retinal layers. Cones have small receptive fields, which yields sharp spatial detail, and they come in three spectral types, enabling color discrimination. This anatomical and functional setup explains why central vision is so detailed and colorful, while rods—more sensitive and located mainly in the periphery—support night vision and broader light sensitivity but with lower spatial resolution.