Question

What is the phototransduction pathway and how a light signal is generated?

Answer 1

Phototransduction is defined as the process of conversion of light signals into elctrical signals in the cone cells, rod cells and ganglion cells of the retina. The process is mediated by G-Protein coupled receptors (opsins). Rods and cones are the photoreceptor cells, which are involved in the vision.

These rods and cones contain protein that absorbs light, leading to the activation of these cells. Rods codes low light level and cones deals with colour vision. The signals generated in these rods and cones are transmitted to neurons. The signals generated in both the eyes meet at area reffered as optic chiasm. Here, these signals are sent to the brain (visual cortex). The signals are finally processed in this part of the brain.