Assertion: carotenoid | /r/HasProperty | unusual
Facets:
value: in plants
type: LOCATION
Source sentences:
text: It has not been determined whether the route to a -carotene biosynthesis is only via the e ring first or if it can also proceed via the b ring first, and carotenoids with two e rings being unusual in plants (Cunningham and Gantt, 1998).