Membrane’s elasticity accepted? There’s risk about that (10)

'membrane's elasticity accepted? there's risk about that' is the definition.
I can't tell whether this defines the answer.

'membrane's elasticity accepted? there's risk about that' is the wordplay.
'membrane's elasticity' becomes 'tone' (I can't explain this - if you can you should give a lot more credence to this answer).
'accepted?' becomes 'a' (financial abbreviation).
'there's' is a charade indicator (letters next to each other).
'risk' becomes 'peril' (synonyms).
'about that' means one lot of letters goes inside another.
'tone'+'a'='tonea'
'tonea' inserted into 'peril' is 'PERITONEAL'.

Can you help me to learn more?