Theory:

Organ_Systems_I.jpg
 
 
Organ_Systems_II.jpg
 
 
9.jpg
Reference:
https://upload.wikimedia.org/wikipedia/commons/d/d8/Organ_Systems_I.jpg
https://upload.wikimedia.org/wikipedia/commons/f/fa/Organ_Systems_II.jpg
https://www.flickr.com/photos/121935927@N06/13537374454/in/photostream/