The diagram above illustrates the digestive tract of a farm animal. Digestion of protein starts in the part labelled

The diagram above illustrates the digestive tract of a farm animal. Digestion of protein starts in the part labelled

Answer Details

The digestion of protein starts in part II of the digestive tract illustrated in the diagram. Part II represents the stomach of the farm animal, where protein digestion begins through the action of enzymes and stomach acids. The stomach lining produces enzymes such as pepsinogen, which is converted to the active enzyme pepsin by the acidic environment of the stomach. Pepsin breaks down protein into smaller peptides and amino acids, which can then be further digested and absorbed in the small intestine. Therefore, part II is where the initial breakdown of protein starts in the digestive process of the farm animal.