1. Human Digestion Anatomy

2. Mouth/Pharynx Teeth chew food into smaller pieces Tongue pushes chewed food to throat

3. Salivary glands Secrete saliva to moisten food Begins the digestion of starches

4. Epiglottis Flap that closes windpipe when swallowing Helps prevent choking

5. Trachea Windpipe, not part of digestive system

6. Esophagus Food tube, connects mouth to stomach

7. Stomach Muscular pouch that mixes food Digestive juices begin breakdown of proteins

8. Pyloric sphincter Do-nut shaped muscle between stomach and duodenum Controls entry of food mass into small intestines Ground up food is called chyme

9. Liver Distribution center for nutrients Makes bile

10. Gall bladder Stores bile for fat breakdown

11. Duodenum of small intestines 1 st 12-14 inches of small intestines Final digestion of food occurs Bile/fats Pancreatic juices/all food types

12. Pancreas Makes enzymes that break down all type of foods

13. Small Intestines Nutrient molecules absorbed into blood stream by villi and sent to liver Ave. length 23 feet

14. Appendix No real function; can become infected and removed by surgery

15. A possible scenario for the progression from a fully functional cecum to the current human appendix was put forth by Charles Darwin. [13] He suggested that the appendix was used for digesting leaves as primates. It may be a vestigial organ of ancient humans that has degraded to nearly nothing over the course of evolution. The cecum enables it to host bacteria that specifically help to break down cellulose. Human ancestors may have also relied upon this system when they lived on a diet rich in foliage. As people began to eat more easily digested foods, they may have become less reliant on cellulose-rich plants for energy. As the cecum became less necessary for digestion alleles became more frequent and the cecum continued to shrink. After millions of years, the once- necessary cecum degraded to be the appendix of todayCharles Darwin [13]primatesalleles

16. Large Intestines Water reabsorbed back into blood Bacteria feed on undigested matter as it moves to rectum

17. Eyes, Nose, Tongue Senses of sight, smell, and taste help to determine food choices and safety

18. Rectum Stores solid waste until ready for removal

19. Anus End of digestive tract; solid waste leaves body Process of elimination is called defecation