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iii. Oesophagus
It is the thin, long muscular tube that extend posteriorly passing through the neck,
thorax and diaphragm and finally leads into a J-shaped bag- like structure called
stomach. A muscular gastro-oesophageal sphincter regulates the opening of
oesophagus into the stomach.
iv. Stomach
It is the most dilated- structure of alimentary canal situated between the oesophagus
and small intestine. It lies below the diaphragm in the abdominal cavity towards the
upper left side.
Pails of Stomach
Stomach has three major parts as given below
(a) Cardiac stomach, the upper portion into which the oesophagus opens.
(b) Fundic stomach, the middle portion.
(c) Pyrolic stomach, the lower portion, which opens into the first part of small
intestine, i.e., duodenum.
The terminal pyrolus part of stomach (i.e., opening of stomach into duodenum) is
guarded by a pyrolic sphincter.

Functions of Stomach
Stomach serves the following Junctions
(a) Acts as a short term storage reservoir.
(h) The substantial chemical and enzymatic digestion is initiated here (especially of
proteins).
(c) Gastric smooth muscles mix and grind the foodstuff by vigorous contractions