Entry 5:Large Intestine

The next part on my research is on the large intestine. Food continues it's journey from the small intestine to the large intestine. The large intestine is the last attraction in digestive tube and the location of the terminal phases of digestion. In comparison to other regions of the tube, there are huge differences among species in the relative size and complexity of the large intestine. From the small intestine, undigested food (and some water) travels to the large intestine through a muscular ring or valve that prevents food from returning to the small intestine. By the time food reaches the large intestine, the work of absorbing nutrients is nearly finished. The large intestine's main function is to remove water from the undigested matter and form solid waste that can be excreted. Material in the large intestine is mostly indigestible residue and liquid. Movements are due to involuntary contractions that shuffle contents back and forth and propulsive contractions that move material through the large intestine. The large intestine is made up of these three parts:

1. The cecum is a pouch at the beginning of the large intestine that joins the small intestine to the large intestine. This transition area expands in diameter, allowing food to travel from the small intestine to the large. The appendix, a small, hollow, finger-like pouch, hangs at the end of the cecum. Doctors believe the appendix is left over from a previous time in human evolution. It no longer appears to be useful to the digestive process.
2. The colon extends from the cecum up the right side of the abdomen, across the upper abdomen, and then down the left side of the abdomen, finally connecting to the rectum. The colon has three parts: the ascending colon; the transverse colon, which absorb fluids and salts; and the descending colon, which holds the resulting waste. Bacteria in the colon help to digest the remaining food products.
3. The rectum is where feces are stored until they leave the digestive system through the anus as a bowel movement.
   

The appendix is a small projection emerging from the caecum. In human beings, the appendix has no known function and is thought to be a remnant from a previous time in human evolution. In some people, the appendix becomes infected or inflammed(appendicitis) and the appendix will need to be removed via surgery.

Information obtained from:
1)http://www.vivo.colostate.edu/hbooks/pathphys/digestion/largegut/index.html
2)http://kidshealth.org/parent/general/body_basics/digestive.html
3)http://www.gesa.org.au/digestive-system/large_intestine.cfm
4)http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookDIGEST.html#Stages%20in%20the%20Digestive%20Process