Certified Paraoptometric (CPO) Practice Exam 2025

Which component is responsible for color vision?

1. Macula

2. Rods

3. Cones

4. Lacrimal Duct

The correct answer is: Cones

The cones are the photoreceptor cells in the retina that are primarily responsible for color vision. They are concentrated in the macula, particularly in a central area known as the fovea, where visual acuity is highest. Cones operate best in bright light conditions and enable the perception of a wide range of colors through three different types of cone cells, each sensitive to different wavelengths of light (short, medium, and long), corresponding to blue, green, and red shades. This is different from rods, which are responsible for vision in low-light conditions but do not detect color. The lacrimal duct has a role in tear drainage, but it does not contribute to vision at all. Thus, the cones are clearly identified as the key components in enabling color perception in our vision.