1. Digestive System Continues

2.  Dental caries = cavities  Brush/floss teeth daily to prevent  Teeth should be cleaned by dental hygienist ever 6 months

5. Gallbladder Small green organ, inferior surface of the liver Stores and concentrates bile until needed by the body. When fatty foods digested, bile released by gallbladder

6. Large Intestine Chyme- semi- liquid food Approx. 2” in diameter Also called the colon Cecum- lower right portion of large intestine Vermiform Appendix- is finger - like projection off cecum Rectum- last portion of large intestine Anus – external opening

7. Digestion Bolus – a soft, pliable ball- created from chewing and addition of saliva- slides down the esophagus Peristalsis – wavelike motions, moves food along the esophagus, stomach and intestines

8. In the Mouth Saliva softens food to make it easier to swallow Ptyalin- in saliva converts starches into simple sugars Under nervous control –just thinking of food can cause your mouth to water

9. In the Stomach Gastric (digestive) juices are released (gastrin, HCL, intrinsic factor, pepsinogen, alkaline mucus, rennin) Stomach walls churn and mix (This mixture is chyme) Small amount of chyme enters duodenum at a time controlled by pyloric sphincter Takes 2-4 hours for the stomach to empty

10. In the Small intestine Where digestion is completed and absorption occurs Addition of enzymes from pancreas and bile form liver/gallbladder

11. Villi increase the internal surface area of the intestinal walls. Increased surface area allows for increased intestinal wall area that is available for absorption. Increased absorptive area is useful because digested nutrients pass into the villi which is semi permeable, through diffusion, which is effective only at short distances. In other words, increased surface area decreases the average distance traveled by nutrient molecules, so effectiveness of diffusion increases. The villi are connected to the blood vessels so the circulating blood then carries these nutrients away.

12. In the Large Intestine Regulation of H2O balance by absorbing large quantities back into the bloodstream Bacterial action on undigested food- decomposed products excreted through colon-bacteria form moderate amounts of B complex and Vitamin K

13. Large intestine cont. Gas formation – 1-3 pints/day, pass it through rectum (flatulence) 14 times a day, bacteria produce the gas Feces – undigested semi- solid consisting of bacteria, waste products, mucous and cellulose Defecation- when large intestine fills, defecation reflex triggered- colon and rectal muscles contract while internal sphincter relaxes external anal sphincter under conscious control

14. Acts of Digestion 1.Ingestion 2.Mastication 3.Digestion 4.Secretion 5.Absorption 6.Excretion