part_of part of part of results in morphogenesis of anatomical structure morphogenesis rhombomere 1 development rhombomere morphogenesis rhombomere 1 morphogenesis The process in which the anatomical structure of rhombomere 1 is generated and organized. Rhombomeres are transverse segments of the developing rhombencephalon. Rhombomeres are lineage restricted, express different genes from one another, and adopt different developmental fates. Rhombomeres are numbered in an anterior to posterior order. biological_process GO:0021651 rhombomere 1