test
node1
BFO:0000003
occurrent
node1->node1
node2
BFO:0000015
process
node1->node2
node5
GO:0008150
biological_process
node2->node5
node3
GO:0048878
chemical homeostasis
node4
GO:0098771
inorganic ion
homeostasis
node3->node4
node8
GO:0055062
phosphate ion
homeostasis
node4->node8
node7
GO:0042592
homeostatic process
node5->node7
node6
BFO:0000001
entity
node6->node1
node7->node3