[[File:CheckOkay.png|20 px]] <b>Necessary properties of these blocks</b>
[[File:UDOM_PlantPartRelations.png|thumb|400px|alt=Relations of plant parts|Possible relations between parts of plant]]
An important aspect of the datamodel has not been discussed yet, namley
[[File:SmileyQuestion.png|20 px]] <b>How are the blocks (=metaclasses) related to each other?</b>
[[File:UDOM_PlantPartRelations.png|400 px]]
=== Relating objects ===