Assertion: giraffe | /r/HasAspect | special valves
Facets:
value: in the vessels in its neck
type: LOCATION
value: to ensure
type: PURPOSE
Source sentences:
text: The giraffe has special valves to protect its brain and keep it from blacking out when it lowers its head to drink; they both constrict and release blood flow.
text: The giraffe has special valves in the vessels in its neck to ensure that the blood flow is adequate.