It measures approximately 1.5 m in length and 6.5 cm in diameter, wraps around the small intestine, in the shape of an arc. It is made up of the cecum, colon, rectum, appendix, anal canal and anus. Around 90% of the water is reabsorbed, which is one of its major functions. There are also bacteria in the large intestine that convert proteins into amino acids. These bacteria produce gas, acid and vitamins B and K by breaking down amino acids. These vitamins are absorbed here. The contents of the large intestine pass to a semi-solid state called stool due to reabsorption of water. (Tortora G. and Derrickson B..