Lundgren 
Lo que comemos y el sistema digestivo [PDF ebook] 
Eating and the Digestive System

This Title Addresses How We Need Food To Fuel Our Bodies. It Teaches Students What Happens During The Digestive Process. How The Saliva Starts The Process And How The Stomach And Intestines Break Down Food So It Can Be Digested Properly. Also Talks About The Digestion System Of Animals (Herbivores, Meat-Eaters)