Brunner's glands are found in which of the following layers?

Define / Explain the following terms:
$(1)$ Diphyodont
$(2)$ Thecodont

The esophagus is a thin,long tube which extends posteriorly passing through the neck,thorax,and diaphragm to lead to a '$J$' shaped bag-like structure called the stomach.

$A$ unique vascular connection between the digestive tract and liver is called

The folds of Kerkring are developed in

Explain the terms thecodont and diphyodont.