​ Rhodopsin ⇌^(Light) Retinal + Opsin a) How is this reaction related to vision?

Question

Rhodopsin  \(\overset{light}\leftrightharpoons\)  Retinal + Opsin

a) How is this reaction related to vision? 

b) How does the deficiency of vitamin A cause poor vision in dim light?

Answer 1

a) 1. When light rays fall rhodopsin dissociate into retinal and opsin.

2. Generates impulses. 

3. When impulses reach the cerebrum vision is experienced.

b) Retinal, the visual pigment found in the photoreceptors, is formed from vitamin A. The deficiency of vitamin A results in the low production of retinal. This, in turn, creates the deficiency of rhodopsin in rod cells. The resynthesis of rhodopsin also gets blocked. This causes a condition called night blindness.