What is the key difference between rods and cones?

What is the key difference between rods and cones?

• A. Rods are more sensitive to light and used for night vision; cones are responsible for color vision.
• B. Rods detect color; cones detect night vision.
• C. Rods detect motion; cones detect edges.
• D. Rods are located in the fovea; cones are in the peripheral retina.

Answer: (C)

Rods and cones differ mainly in how they respond to light and what kind of vision they support. Rods are highly light-sensitive and enable vision in dim conditions, but they do not detect color and provide lower visual acuity. Cones require brighter light, provide color vision, and give high-acuity, detailed central vision. The location difference—cones in the fovea for sharp central vision and rods more plentiful in the peripheral retina—also reinforces this distinction. So the core idea is night vision without color for rods versus bright-light color vision with fine detail for cones.

Rods and cones differ mainly in how they respond to light and what kind of vision they support. Rods are highly light-sensitive and enable vision in dim conditions, but they do not detect color and provide lower visual acuity. Cones require brighter light, provide color vision, and give high-acuity, detailed central vision. The location difference—cones in the fovea for sharp central vision and rods more plentiful in the peripheral retina—also reinforces this distinction. So the core idea is night vision without color for rods versus bright-light color vision with fine detail for cones.