Assertion: esophagus | /r/HasProperty | extended towards lower end
Facets:
value: in some birds
type: LOCATION
value: to form a crop
type: PURPOSE
Source sentences:
text: In the majority of vertebrates, the esophagus is simply a connecting tube, but in some birds, which regurgitate components to feed their young, it is extended towards the lower end to form a crop for storing food before it enters the true stomach.