Large Intestines

The large intestine is the last part of the digestive system. Its main responsibility is to absorb water from the “indigestible” food matters and store “useless” nutrients (termed as “wastes”) to flush them out of the body. It has two parts, the cecum and colon.

One-fifth of the whole length of the intestinal canal belongs to the large intestine, as it measures about 1.5m long.

Food digestion completely ends in the small intestine, particularly in the ileum. Once the digested material reaches the large intestine, the water and nutrients present in it are absorbed. The large intestine takes 12-25 hours to finish this process.

The large intestine is “largely” different from the small intestine. The most obvious reason for this is the fact that the large intestine is wider than the latter.  The two also have different properties.  The large intestine has invaginations (intestinal glands), different from what the small intestine has (villi). Also, goblet cells (cells whose main function is to secrete mucus) are more abundant in the large intestine.

The large intestine is also a house to over 700 species of bacteria that perform a variety of important functions. Some of these bacteria aid in the digestion of food materials that the small intestine failed to digest. Some of them also produce small amounts of vitamins (mostly vitamin K and Biotin, a B vitamin) for the blood. The most prevalent bacteria in the large intestine are the bacteroids. Bifidobacteria, the “friendly bacteria,” are also abundant.