the nervous system is a kind of body system
nervous_system is not system. nervous_system is body_part. nervous_system is system. nervous_system_in is nervous_system. vertebrate_nervous_system is nervous_system. human_nervous_system is vertebrate_nervous_system. sympathetic_nervous_system is nervous_system. human_nervous_system is body_part. nervous_system is not body_part. human_nervous_system is nervous_system.