Final answer:
Visual transduction is the process that allows rod and cone cells to become more sensitive to light through chemical changes initiated by the alteration of retinal within photopigments.
Step-by-step explanation:
The process whereby the rod and cone cells undergo chemical changes that make them more sensitive to light is known as visual transduction. When light hits a photoreceptor, it changes the shape of a molecule called retinal, which is a component of the photopigment rhodopsin found in rods and different opsins found in cones. This chemical alteration is initiated by the isomerization of retinal from a bent (cis) form to a linear (trans) form, which in turn activates these photopigments. The activation sequence eventually causes the photoreceptor cell to change its membrane potential and modify the release of neurotransmitters. This sensitivity adjustment allows us to see in varying light conditions.