Opt for some science lectures (5)
I believe the answer is:
elect
'opt' is the definition.
(I've seen this in another clue)
'some science lectures' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'ELECT' is hidden within 'science lectures'.
'for' acts as a link.
(Other definitions for elect that I've seen before include "Choose for Parliament, say" , "special people" , "Waiting to get into office" , "Put in power by voting" , "Choose by ballot" .)