Internal anatomy of a Turtle Reptile Diagram! This learning resource contains a diagram for the internal anatomy of a turtle. Answer key and lined student sheet included! Internal organs included in this booklet: turtle, brain, heart, respiratory system, trachea, lungs, digestive system, buccal cavity, esophagus, stomach, liver, gallbladder, pancreas, small intestine, large intestine, kidney, bladder, and cloaca. If you would like to expand on this topic, check out my internal parts of a turtle