The different parts of the digestive system are as follows:
1. Buccal cavity opens outside through the mouth. It has the tongue, teeth and the opening of the salivary gland.
2. Buccal cavity leads to oesophagus.
3. The oesophagus opens into the stomach. The wall of the stomach contains gastric glands.
4. The stomach opens into the duodenum. This opening is regulated by a sphincter muscle which releases small amount of food at a time.
5. The duodenum receives the secretions of the liver and the pancreas.
6. From the duodenum, the food passes into the small intestine. The inner wall of the small intestine has a number of finger like projections called villi. The villi increases the surface area and are richly supplied with blood vessels.
7. The small intestine opens into the large intestine.
8. The terminal portion of the large intestine is called the rectum that opens out through the anus.
