Sentence:  A study of their activity on thyroglobulin has shown that thyroxine is not preferentially released and that the <WSD>degradation</WSD> proceeds stepwise with the formation of macromolecular intermediates ( Alpers , Petermann and Rall , 1956 ) . 
Meaning of the word marked with <WSD> tags:  changing to a lower state (a less respected state)