Final answer:
The pigment responsible for night vision is rhodopsin, a photopigment found in the rod cells of the retina, consisting of opsin and retinal.
Step-by-step explanation:
The pigment that is responsible for night vision is called rhodopsin. Rhodopsin is a photopigment molecule found in the rod cells of the retina.
It is incredibly sensitive to light, allowing it to function in low light conditions which is why it is integral to night vision. Rhodopsin consists of a protein called opsin and a cofactor called retinal, which undergoes a biochemical change when struck by photons in a process known as photoisomerization.
Specifically, this process converts 11-cis-retinal to all-trans-retinal, enabling the detect of light and playing a crucial role in the visual cycle of the eye.
Additionally, in the rhodopsin cycle, trans-retinal is enzymatically converted back into its active cis form, which recombines with opsin to regenerate rhodopsin for further visual perception.