the digestion system


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the digestion system

  1. 1. Mukuya gervasius 201302586 subject: Natural science and health education Topic: digestion system Grade: 7 mukuya201302586
  2. 2. Digestion system  Definition: The breakdown of food substances into soluble substances. Food such as: Meat Vegetable Cereals mukuya201302586
  3. 3. Human digestion system mukuya201302586
  4. 4. Functions of digestion system parts The mouth • When you chew food, your teeth chop and grind it up into smaller pieces. • Glands in the mouth produces saliva which has enzyme called amylase • Amylase breaks down the carbohydrates in the food. • After you have chewed the food and mixed with the saliva, it is now called a bolas. • As you swallow, the bolas passes through the pharynx. mukuya201302586
  5. 5. Functions of digestion system parts continues……. The Esophagus • This is a long muscular tube which joins the mouth and the stomach. • It contracts and forces the food down, this muscular contraction is called peristalsis. mukuya201302586
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  7. 7. The sphincter  They are found at the end of the esophagus.  It lets food into the stomach but stops it from coming back up the esophagus. mukuya201302586
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  9. 9. The stomach  The bolus eventually reaches the stomach which is a sack- like structure.  The stomach muscle mixes the food with hydrochloric acid and pepsin which is the digestive enzyme that break down protein.  These mixture is called chyme. mukuya201302586
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  11. 11. The small intestine  The chyme passes through another sphincter muscles into the small intestine.  The duodenum, jejunum and ileum form the small intestine. mukuya201302586
  12. 12. The small intestine mukuya201302586 • Final digestion happen in the duodenum, chyme mixes with bile. • Bile breaks up fat into small particles, enzyme from glands in the intestine and pancreas are added. • The digested chyme passes into the jejunum and ileum where cells called villi absorb the nutrients and move them into the blood stream.
  13. 13. The large intestine  Large intestine , also called colon and ends at the rectum.  The colon removes water and some minerals from the digested food which is left and changes it into faeces.  The body passes out the faeces through the anus which is the sphincter muscle that closes off the rectum from the outside the body. mukuya201302586
  14. 14. Reference list Wikispaces,(2013)plant and Animal Systems. The digestive system. retrieved on September 09 2013, retrieved from Healthpages,(2013).anatomy and function of the digestive system. retrieved on September 08 2013,.retrieved from Rose, E,. Nicola, T,. Nocolaas, O,. Semantha, B,. (2005). Natural science and health in context. Human body:digestion. Pg 125-127. Antoine, M,. Denis, H,. (2010). Captioned anatomical structures of mediastinum and thorax in transverse sections. Retrieved on September 10 2013, retrieved from Anatomy/Thorax-Abdomen-Pelvis/Mediastinum-Illustrations Ravinder, K,. Raj, K,. Mittal, G.(2006). Sphincter mechanisms at the lower end of the esophagus. Nature. Retrieved on September 07 2013, retrieved from mukuya201302586