1) No, they do not! The descriptions are largely for flavor/to guide people if they want to RP searching or resources, and those things are all considered to generally not be part of the Pokemon or else they can regrow them easily. Thread and silk and pollen and that sort of thing may be easily found in the forest abandoned by their makers.

2) Yes, that's fine.

3) It's a mystery to us all; however you want to play this is fine. It may also be ignored.

4) There was actually a note made in the Culture section a few days ago on this!