test
node1
BFO:0000001
entity
node2
BFO:0000003
occurrent
node1->node2
node2->node2
node7
BFO:0000015
process
node2->node7
node3
GO:0009605
response to external
stimulus
node4
GO:0009991
response to
extracellular
stimulus
node3->node4
node5
GO:0050896
response to stimulus
node5->node3
node6
GO:0008150
biological_process
node6->node5
node7->node6