<P> The avian stomach is composed of two organs , the proventriculus and the gizzard that work together during digestion . The proventriculus is a rod shaped tube , which is found between the esophagus and the gizzard , that secretes hydrochloric acid and pepsinogen into the digestive tract . The acid converts the inactive pepsinogen into the active proteolytic enzyme , pepsin , which breaks down specific peptide bonds found in proteins , to produce a set of peptides , which are amino acid chains that are shorter than the original dietary protein . The gastric juices ( hydrochloric acid and pepsinogen ) are mixed with the stomach contents through the muscular contractions of the gizzard . </P>
<P> The avian stomach is composed of two organs , the proventriculus and the gizzard that work together during digestion . The proventriculus is a rod shaped tube , which is found between the esophagus and the gizzard , that secretes hydrochloric acid and pepsinogen into the digestive tract . The acid converts the inactive pepsinogen into the active proteolytic enzyme , pepsin , which breaks down specific peptide bonds found in proteins , to produce a set of peptides , which are amino acid chains that are shorter than the original dietary protein . The gastric juices ( hydrochloric acid and pepsinogen ) are mixed with the stomach contents through the muscular contractions of the gizzard . </P>
what is the top part of a birds stomach called
what is the top part of a birds stomach called
proventriculus
proventriculus