test
node1
BFO:0000003
occurrent
node1->node1
node4
BFO:0000015
process
node1->node4
node2
GO:0008150
biological_process
node3
GO:0009987
cellular process
node2->node3
node5
GO:0098743
cell aggregation
node3->node5
node4->node2
node6
GO:0098630
aggregation of
unicellular organisms
node5->node6
node7
BFO:0000001
entity
node7->node1