part of part of has part has part adjacent to adjacent to photoreceptor outer segment layer of retina pigmented layer of retina photoreceptor layer of retina photoreceptor outer segment layer ZFA:0001466 VHOG:0001173 MA:0002472 UBERON:0003926 retina photoreceptor layer outer segment (...) an essentially similar sequence of events occurs during the embryonic development of the vertebrate eye. The eye initially develops as a single median evagination of the diencephalon that soon bifurcates to form the paired optic vesicles. As each optic vesicle grows towards the body surface, its proximal part narrows as the optic stalk, and its distal part invaginates to form a two-layered optic cup. (...) The outer layer of the optic cup becomes the pigment layer of the retina, whereas the inner layer differentiates into the photoreceptive cells and neuronal layers of the retina.[well established][VHOG] photoreceptor outer segment layers TAO:0001466 EMAPA:35688