test
node1
BFO:0000001
entity
node2
BFO:0000002
continuant
node1->node2
node2->node2
node3
BFO:0000004
independent
continuant
node2->node3
node3->node3
node4
BFO:0000040
material entity
node3->node4
node5
PO:0025131
plant anatomical
entity
node4->node5
node6
PO:0009011
plant structure
node5->node6
node7
PO:0000003
whole plant
node6->node7
node8
PO:0030027
thallus
node7->node8