Which is the load bearing wall?
You cannot really tell what is load bearing or not just from pictures of finished space. Your best bet would be if there were blue prints of the original build of the house to to analyze. Walls perpendicular to joists can very well be load bearing if there are joist that span to that partition and then overlap with another that extends to the next supporting wall.
There could be other factors to consider such as these for some examples:

Shorter joists were used in some instances so that they could take more load from the floor above.
The wall may be located directly under a partition wall on the floor above that is itself a supporting wall.