Table 3.

Ontology class relations for both mouse and human lung

Relations	Examples
part_of	“left lung bronchiole” is part_of “left lung”
is_a	alveolar epithelium is_a epithelium “lymphatic endothelial cell” is a “endothelial cell”
adjacent_to	“basement membrane” is adjacent_to “alveolar epithelium” “pericyte” is adjacent_to “alveolar capillary endothelium”
branching_part_of	“lateral bronchiole” is a branching_part_of the “central bronchiole” “terminal bronchiole” is a branching_part_of the “lateral bronchiole” “alveolar duct” is a branching part of “the terminal bronchiole”
develops_from	“alveolus” develops_from “pre-alveolar terminal saccule”, which develops_from “pre-alveolar acinar tubule” “secondary alveolar septum” develops_from “alveolar septal crest”, which develops_from “primary alveolar septum”
continuous_with	“trachea” is continuous_with “bronchus”, which is continuous_with “central bronchiole”