Figure 2From: Simulation-based model checking approach to cell fate specification during Caenorhabditis elegans vulval development by hybrid functional Petri net with extensionBasic elements of HFPNe and examples of biological icons in Cell Illustrator. In Cell Illustrator [24–26], HFPNe elements are replaced with the biological icons defined in the Cell System Ontology [47]. This replacement makes the HFPNe model of a biological pathway more comprehensible (see [17] for details).Back to article page