stomach

an expansion of the ALIMENTARY CANAL that lies between the OESOPHAGUS and the DUODENUM . It has thick walls of smooth MUSCLE that contract to manipulate the food, and its exits are controlled by SPHINCTERS , the cardiac anteriorly and the pyloric at the junction with the duodenum (see PYLORUS ). Mucosal cells in the lining secrete GASTRIC JUICE . The food is reduced to an acidic semi-liquid that is moved on to the duodenum. The stomach varies in size but its greatest length is roughly 30 cm and the breadth 10 to 12 cm. Its capacity is approximately 1 to 1 1 / 2 litres.