Which cells in the retina detect light?

Which cells in the retina detect light?

• A. Rods
• B. Cones
• C. Rods and cones
• D. Ganglion cells

Answer: (C)

Light detection in the retina is carried out by photoreceptor cells—the rods and cones. These cells contain photopigments that respond to photons and trigger phototransduction, changing their membrane potential and neurotransmitter release. Rods are extremely sensitive and work well in dim light, supporting night vision but not color or fine detail. Cones require brighter light and come in types that detect different wavelengths, enabling color vision and high visual acuity, especially in the central retina where cones are concentrated (the fovea). Ganglion cells are the output neurons that relay processed visual information to the brain after it has passed through photoreceptors and interneurons; they do not detect light directly in the way rods and cones do. There is a small subset of retinal ganglion cells that respond to light for non-image tasks, but for forming the image, rods and cones are the primary detectors.

Light detection in the retina is carried out by photoreceptor cells—the rods and cones. These cells contain photopigments that respond to photons and trigger phototransduction, changing their membrane potential and neurotransmitter release. Rods are extremely sensitive and work well in dim light, supporting night vision but not color or fine detail. Cones require brighter light and come in types that detect different wavelengths, enabling color vision and high visual acuity, especially in the central retina where cones are concentrated (the fovea). Ganglion cells are the output neurons that relay processed visual information to the brain after it has passed through photoreceptors and interneurons; they do not detect light directly in the way rods and cones do. There is a small subset of retinal ganglion cells that respond to light for non-image tasks, but for forming the image, rods and cones are the primary detectors.