Question

Which of the following statements is correct regarding rods and cones in the human eye?

• A. Cones are sensitive to dim light.
• B. Cones are sensitive to bright light.
• C. Rods are sensitive to bright light and dim light.
• D. Rods can sense colour.

Answer 1

The correct option is B Cones are sensitive to bright light.

The retina is the back part of the eye that contains the cells that respond to light. These specialized cells are called photoreceptors. There are 2 types of photoreceptors in the retina: rods and cones.
The rods are most sensitive to light intensity changes. They contain only one type of light-sensitive pigment. Rods are not good for color vision. In a dim room, however, we use mainly our rods, but we are color blind. Rods are more numerous than cones in the periphery of the retina. There are about 120 million rods in the human retina.

The cones are less sensitive to light. However, cones are more sensitive to one of three different colors (green, red or blue). Signals from the cones are sent to the brain which then translates these messages into the perception of color. Cones, however, work only in bright light.