|
Profile
Dylan Han(6) 2-5 Topic Chosen 1: Digestion Topic Chosen 2: Issues on Sex Links and Credits linkone linktwo Layout: hearteditorials Codes: -ambulance Icon: biconcave |
Monday, July 28, 2008
E-learning Day 17: 28 July 2008
This marks the final entry I shall be writing with regards to the topic of digestion. What are the basic functions of the large intestine, rectum and anus in the digestion of food? For this entry, I used the search engine http://google.com.sg/ to look for materials regarding these organs, and utilized http://wikipedia.org/ to look for an article related to each individual organs. After looking through my previous entries, I realized I have summarized the functions of the colon/large intestine prior to today. However, I will recap the functions of the organ in a few points. Functions of the large intestine: -no digestive enzymes produced -bacteria present break down the cellulose/glucose -remaining water is removed from the chyme (food "mush") -chyme is mixed with mucus and bacteria and forms feces -dietry fibre and waste products of the above process are used as nutrition The rectum is about 8 inches (12cm) long and is a "warehouse" for waste products to be excreted. Folds in the rectum known known as transverse folds keep the waste in place till they are ready to be discharged. The anus is an opening through which feces passes out from. Pressure builds up in the rectum. This pressure is increased by abdominal and pelvic floor muscles. The internal anal sphincter (a ring of muscle surrounding the anus) relaxes. The rectum shortens as the feces enter the anal canal and the relaxed sphincters (both internal and external) allows the feces to exit the anus. This ends my final post on digestion. I have enjoyed researching on the digestive system for the past few weeks, and have gained some knowledge on the digestive system of humans and also birds. I have also learnt some other facts such as how vomiting occurs. Sources: http://en.wikipedia.org/wiki/Rectum http://coloncancer.about.com/od/faqs/f/Rectum.htm http://www.gesa.org.au/digestive-system/anus.cfm http://en.wikipedia.org/wiki/Anus |