<Tr> <Td_colspan="2"> Anatomical terms of neuroanatomy (edit on Wikidata) </Td> </Tr> <P> Rod cells are photoreceptor cells in the retina of the eye that can function in less intense light than the other type of visual photoreceptor, cone cells . Rods are usually found concentrated at the outer edges of the retina and are used in peripheral vision . On average, there are approximately 90 million rod cells in the human retina . Rod cells are more sensitive than cone cells and are almost entirely responsible for night vision . However, rods have little role in color vision, which is the main reason why colors are much less apparent in dim light, and not at all at night . </P> <P> Rods are a little longer and leaner than cones but have the same basic structure . Opsin - containing disks lie at the end of the cell adjacent to the retinal pigment epithelium, which in turn is attached to the inside of the eye ball . The stacked - disc structure of the detector portion of the cell allows for very high efficiency . Rods are much more common than cones, with about 100 million rod cells compared to 7 million cone cells . </P> <P> Like cones, rod cells have a synaptic terminal, an inner segment, and an outer segment . The synaptic terminal forms a synapse with another neuron, usually a bipolar cell or a horizontal cell . The inner and outer segments are connected by a cilium, which lines the distal segment . The inner segment contains organelles and the cell's nucleus, while the rod outer segment (abbreviated to ROS), which is pointed toward the back of the eye, contains the light - absorbing materials . </P>

How do rod cells work in the eye