People with normal color vision have more _______ receptors than _______ receptors, and the precise proportions of these receptors _______ among individuals.
A) S; M; can vary
B) S; M; are always the same
C) L; M; can vary
D) L; M; are always the same

Question

Quizplus · Accepted Answer

People with normal color vision have more L (long-wavelength-sensitive) receptors than M (medium-wavelength-sensitive) receptors, and the precise proportions of these receptors can vary among individuals. Option A is incorrect because S (short-wavelength-sensitive) receptors are not more abundant than M receptors. Option B is incorrect because the proportions of S and M receptors can vary among individuals. Option D is incorrect because L and M receptors are not always present in equal amounts.

People with Normal Color Vision Have More _______ Receptors Than