herbivorous mammals than carnivorous. The junction of ileum with cecum is guarded by the ileocecal valve. The function of this valve is to prevent backflow of fecal contents from colon to ileum. The valve can resist back pressure of at least 50 to 60 cm of water.

The main functions of colon are

1. Absorption of electrolytes and water from chyme.
2. Temporary storage of fecal matter.

The proximal region of colon concerned mainly with absorption and distal region with storage. The colon has three longitudinal bands called teniae coli and small pouches called haustra. Thus the mixing movement in colon is called as haustration. The movement in colon are sluggish.
The lower portion of descending colon is sigmoidal in shape and opens into rectum. It is 20 cm long and terminates in the 2 cm long anal tract. When a mass movement propels feces into rectum, the desire for defecation occurs.
The opening of anal tract is called anus. The anus has two sphincter. Internal anal sphincter composed of smooth muscle fibre and external anal sphincter composed of striped muscle fibre (voluntary in nature). The moderate quantities of vitamin B complex and vitamin K also found by bacteria in large intestine.

 

2. Secretary Glands: The primary function of secretary glands is the secretion of digestive enzymes for digestion of food and mucus for lubrication and protection of tract. Most digestive secretion occurs in precise amount only in response to the presence of food in alimentary tract. We have discussed major digestive glands.