Assertion: breast's gland | /r/HasProperty | maintained by lineage-committed progenitors3
Facets:
value: in adulthood
type: TEMPORAL
Source sentences:
text: Some have suggested that bipotential stem cells are only present during development, and in adulthood the mammary gland is maintained by lineage-committed progenitors3, while others proposed the emergence and expansion of some progenitors only during pregnancy4.