test
node1
GO:0003008
system process
node2
GO:0003013
circulatory system
process
node1->node2
node6
GO:0008015
blood circulation
node2->node6
node3
BFO:0000001
entity
node4
BFO:0000003
occurrent
node3->node4
node4->node4
node5
BFO:0000015
process
node4->node5
node7
GO:0008150
biological_process
node5->node7
node8
GO:0032501
multicellular
organismal process
node7->node8
node8->node1