Role of a BSA

[cognostechie]

I am a technical person but have also been playing this role for a while but have always wondered about
what is the role of a Business Systems Analyst considering that person is supposed to wear only that hat?

1> Does he/she just gather requirements form the business community or also does source-to-tager mappings and also makes documentation of source-to-target mappings?
2> Does that person also does project management?

or does all of this depends on the company size or how that company defines his/her role?