Know more about the digestive system and each organ's function.

Mouth
Food is ingested into the gastrointestinal tract through the mouth, or oral cavity. Associated accessory organs such as the teeth, tongue and salivary glands begin the processes of mechanical and chemical digestion through mastication. The mouth also begins the propulsive process of swallowing.

Pharynx
From the mouth, food is passed into the oropharynx and then to the laryngopharynx. Sequential contractions of the muscles in the wall of the gastrointestinal tract create a peristaltic wave, squeezing the food into the oesophagus.

Oesophagus
Contraction of the muscular wall of the oesophagus creates a peristaltic wave which continues to propel the food along the gastrointestinal tract and into the stomach.

Stomach
The stomach acts as a temporary storage site for food where chemical digestion of proteins begins, and food is converted into chyme. Mechanical digestion is also carried out as peristaltic waves mix the food with gastric juice. A few fat soluble substances are also absorbed through the lining of the stomach into the blood stream.

Small Intestine
The small intestine is the body’s main digestive organ, where digestion is completed and virtually all the absorption of the digestion products into the blood stream occurs. Mechanical digestion and propulsion of the food through the gastrointestinal tract is achieved by the alternate contraction of the smooth muscles of the small intestine wall. Enzymes conveyed via ducts from the pancreas, liver and gallbladder (accessory organs), together with enzymes secreted from the cells lining the small intestine function to chemically digest the food. The soluble digestion products are taken up into the blood stream by passive and active mechanisms.

Large Intestine
The large intestine functions to absorb water from the indigestible food residues in its lumen, and then remove the semi-solid faces from the body through defecation. Faces are propelled through large intestine via peristaltic waves, mass movements and haustral churning. Defecation is a reflex action which is triggered by rectal distension.