Fig. 2

Cell ontology. General and specific cell types are organized into a separate tree of the ontology by developmental age (age_range) and then alphabetically. a There are 13 general cell classes for the mouse at P0-P3. The general cell type, epithelial cell, has four major subclasses: alveolar, bronchial, bronchiolar, and tracheal epithelial cells. b Each of these subclasses can be expanded into specific cell types, illustrating their distribution in the conducting airway and alveoli. A subclass termed isolated lung cell types was created for experimental cell types/subtypes identified by scRNA seq analysis