It is part of the digestive AND respiratory tracts. The esophagus is muscular tube that connects the pharynx to the stomach. Muscular contractions move the food down the esophagus to the stomach. The stomach is located in abdominal cavity between the esophagus and small intestine. It is divided into three regions, the cardiac, fundus and pylorus.
Protein is the primary food component broken down in the stomach.
Ask why this is important to know. The abomasum is the true stomach. The lighter food collects in the rumen. The abomasum is the true stomach with typical enzyme action. The food remain here for a relatively short time compared with the time in the rumen.