Movements of Small Intestine: The small intestine is continuous with the stomach at the sphincter and leads into the large intestine at the ileocaecal valve. It is 5 meters long and lies in the abdominal cavity surrounded by the large intestine. The important function of the small intestine is the absorption of nutrients.
- The small intestine comprises 3 main sections continuous with each other they are:
Table of Contents
- The duodenum is about 25 cms long secretions from the gall bladder and pancreas are released into the duodenum through a common structure known as the sphincter of Oddi or Hepatopancreatic sphincter.
- It is the middle section of the small intestine and is about 2mts long.
- It is about 3 meters long and ends at the ileocaecal valve which controls the flow of material from the ileum to the caecum, the first part of the large intestine, and prevents regurgitation.
Movements of the small intestine:
Three types of movements are seen they are
- Peristalsis: It is a wave of contraction preceded by the wave of relaxation. This movement helps in propelling the chyme. The speed of peristalsis in jejunum and ileum is 1.2-2.5 cm-sec. This type of movement is initiated by neurogenic drive.
- Segmentation: In this type of movement, circular muscles contract at regular Intervals thus dreading the intestine into several segments. This type of movement helps in the mixing of food with digestive juices and absorption of digested food.
- Pendular: This movement is similar to segmentation but here segments move to and fro over the food in the Pendular fashion at the rate of 5 cm/sec. This type of movement helps in the mixing of food with digestive juices and absorption of the digested food.
|QUESTION BANK |
1. Explain the Movements of the small intestine.