Takes on or assumes (6)
I believe the answer is:
adopts
I believe this clue is a double definition.
'takes on' is the first definition.
('adopt' can be a synonym of 'take on')
'assumes' is the second definition.
('adopt' can be a synonym of 'assume')
(Other definitions for adopts that I've seen before include "Takes as one's own, say child" , "Takes or uses as one's own" , "Legally takes on (child)" , "Takes into one's family legally" , "Takes as heir or representative" .)