A complete lack of color vision is very rare and occurs when an individual has:
A)only two types of cones.
B)only one type of photoreceptor, rods.
C)an excessive number of cones.
D)a complete lack of red cones.

Question

Quizplus · Accepted Answer

A complete lack of color vision, known as achromatopsia, occurs when an individual has only rods, which are photoreceptors that do not detect color.

A Complete Lack of Color Vision Is Very Rare and Occurs