Note that it is safer to bring in a professional from your province or state to confirm whether a wall is structural or load bearing. A professional will take a holistic look at the structure and confirm how load is distributed down to the foundation. The professional will assess as well whether the wall in question works within the lateral resisting system (earthquake or wind force resisting system).
That being said, there are few triggers to look for which will help you determine that a wall is structural or that its time to call in a licensed professional.
-Is the wall framed with two top plates?
-Is there overlapping floor joists or ceiling joists resting on the top of the wall ?
-Are wall openings framed with load bearing headers?
-Is the wall framed and sheathed with wood based panels (i.e. plywood or OSB)
-Is the wall anchored down to a concrete footing or to the floor system with more than typical nailing?
If you see any of the triggers above, please consult a structural engineer. If you would like clarifications on any of the points above, please give us a call. We can discuss your project more in depth. Having specifics will help us giving you more guidance.