test
node1
BFO:0000003
occurrent
node1->node1
node2
BFO:0000015
process
node1->node2
node3
GO:0008150
biological_process
node2->node3
node4
GO:0050896
response to stimulus
node3->node4
node5
GO:0051606
detection of stimulus
node4->node5
node7
GO:0009719
response to
endogenous stimulus
node4->node7
node8
GO:0009726
detection of
endogenous stimulus
node5->node8
node6
BFO:0000001
entity
node6->node1
node7->node8