I was at the eye doctor today for my biannual check-up (all good). Since part of the test was a retina scan, I thought I’d refresh my knowledge of rods and cones in the retina. The human retina contains about 120 million rod cells, and 6 million cone cells. Check out the diagram below for a primer on how the retina works.
Biologists are still learning about all the cells and proteins and chemistry involved in vision. For example, in 2008 a team of Japanese researchers discovered a lightning-fast protein involved in the precise interactions between what is called the photoreceptor ribbon synapse and the bipolar dendrites. They promptly named the protein Pikachurin, after Pikachu, the lightning-fast Pokémon creature.