Sentence:  Creating a complete map of the human connectome would therefore be a monumental milestone but not the end of the journey to understanding how our brains work. The achievement will transform neuroscience and <WSD>serve</WSD> as the starting point for asking questions we could not otherwise have answered,nb.... 
Meaning of the word marked with <WSD> tags:  To have a given use or purpose; to function (for) something or "to do" something. (from 14thc.)