Human alimentary canal consists of organs of digestion which are namely, in sequence, mouth, oesophagus, stomach, small intestine, large intestine and anus.
Mouth cavity: It is the oral cavity inside mouth, containing teeth, tongue and three pairs of salivary glands.
Pharynx: The oral cavity opens into the pharynx. It is the part where food passage and air passage cross each other.
Oesophagus: It is a long muscular, tube that passes through thoracic cavity and diaphragm into abdominal cavity and carries the food down to the stomach by peristalsis.
Stomach: The stomach is a thick-walled, J-shaped organ present on the left side of the abdominal cavity and is continuous with the esophagus above and the duodenum of the small intestine below.
Small intestine: The pyrolic valve of Stomach leads to a tubular structure called as small intestine. It has three divisions, i.e., duodenum, jejunum and ileum.
Large intestine: The ileoceacal valve of small intestine leads to large intestine, which can be divided into two parts as anterior colon and posterior rectum.
The rectum opens at the anus, which in turn serves as site of defecation, the expulsion of feces.