Only if they are in work related matters. Do not try and fit other answers into other sections - it rarely works well and you can be “marked down” for it.
Thank you, @Jessica Booker! One of these positions of responsibility is paid (albeit not a lot!), so I'll leave that in. Just as a follow-up, if the title of one of the unpaid positions of responsibility is "co-founder" and is non-university affiliated, can I put this down under work experience?