These are pop-up medical books, or rather videos of some of those books being flipped-through. Whitney Trettien, Rachel Ingold, and Meg Brown of Duke University created the videos. The videos, being silent*, feature silent organs. (Thanks to Laughing Squid and @JenLucPiquant for bringing them to our attention.)
*Well, not entirely silent. You can hear some unexciting dialog, said softly, beginning around the 5:20 mark.