Ganglion cells receive abundant synapses from bipolar neurons, and are the third main link in transmission of visual information. True action potential generated here. Appears like line with light microscopy. These are the only photosensitive components. The discs of the rods and cones contain visual pigments.
Light causes conformational change from cis to trans in the membrane of the disc.
Trans is unstable and dissociates from opsin. This increases outward conduction of calcium, which reduces membrane permeability to sodium. This change in membrane permeability causes hyperpolarization and generation of receptor potential, which leads to production of further electrical signals to the brain eventually interpreted as vision. Layer of rods and cones receive and transduce light signals. Transmit to bipolar neurons.