The molecular mechanism by which light is absorbed into visual systems is
A) oxidation of the rhodopsin molecule.
B) a change in shape of the opsin protein.
C) depolarization of the rhodopsin molecule.
D) transformation of vitamin A into rhodopsin.
E) a shift between isomers of the retinal molecule.

Question

Quizplus · Accepted Answer

Light is absorbed by the photopigment molecule in the retina, which consists of a chromophore (11-cis-retinal) and an opsin protein. When light is absorbed, the chromophore undergoes a conformational change into its trans form, leading to a change in shape of the opsin protein. This triggers a cascade of biochemical events that ultimately lead to the perception of light by the brain. Therefore, the correct answer is E, which describes the shift between isomers of the retinal molecule.

The Molecular Mechanism by Which Light Is Absorbed into Visual