Given some of what life depends on (3)
I believe the answer is:
fed
'given' is the definition.
('feed' can be a synonym of 'give')
'of what life depends on' is the wordplay.
'FED' is hidden within the letters.
But, I am not sure how the hidden word is indicated.
'some' is the link.
Can you help me to learn more?
(Other definitions for fed that I've seen before include "US agent" , "Given sustenance" , "supplied with power?" , "Nourished" , "Given food to eat" .)