A poser scene saved from Poser is a .pz3 or pzz file. Its a single file unless you use external binary morphs. (not suggested)

That is saved from the poser File menu , save or save as.

anything else like figure,pose, material is a subset of the scene file.

The scene file should be complete in itself, only referencing geometry or image files , everything else should be in the pz3.

What Darkedge asked too.