2. Amanda Dermer Amanda Dermer Keane Archibald Keane Archibald Dayana Jimenez Dayana Jimenez Courtney Blazer Courtney Blazer

3.  Chapter 18: Lesson 1  Eight Graders  Age: 13-14  Digestion  Absorption  Elimination

4. Digestive System  The purpose  define the function of each organ  the pathway food takes through the digestive tract

5. Digestive System The organs and parts of the digestive pathway: The organs and parts of the digestive pathway: Oral cavity Oral cavity Pharynx Pharynx Esophagus Esophagus Stomach Stomach Small Intestine Small Intestine Large Intestine Large Intestine

6. Digestive System Teeth Tongue Liver Pancreas

7. Digestion The process that breaks down food into substances that can be absorbed by the body for energy, growth, and repair.

8. Ingestion: Mouth, Teeth & Tongue The function of the mouth is to ingest food sources The function of the mouth is to ingest food sources The teeth are used for mastication The teeth are used for mastication breaking food down into smaller pieces to be breaking food down into smaller pieces to be The tongue forms food into a ball to prepare for swallowing The tongue forms food into a ball to prepare for swallowing

9. Ingestion: Mouth, Teeth & Tongue The mouth, teeth, and tongue play a role in mechanical digestion. The mouth, teeth, and tongue play a role in mechanical digestion. Mechanical digestion physically prepares food for chemical digestion by enzymes. Mechanical digestion physically prepares food for chemical digestion by enzymes.

10. Salivary Glands Secretes saliva a watery solution containing an enzyme that starts the digestion Cleanses the mouth Dissolves food chemicals Moisten food

11. Salivary Glands The salivary glands begin the process of chemical digestion. The salivary glands begin the process of chemical digestion.

12. Pharynx After leaving the mouth, food is passed on to the pharynx. As you swallow: Uvula: prevents food from passing into the nasal cavity. Epiglottis: prevent food from entering the respiratory tract.

13. Esophagus Primary Function; Primary Function; Carry foods and liquids to stomach Carry foods and liquids to stomach Peristalsis moves food though the digestive tract Peristalsis moves food though the digestive tract Food passes through the pharynx into the esophagus Extends from the pharynx to the stomach

14. Stomach Located below the esophagus Located below the esophagus A hollow, saclike organ A hollow, saclike organ Consists of three layers of muscles Consists of three layers of muscles Flexible, allowing it to expand when you eat. Flexible, allowing it to expand when you eat.

15. Stomach A temporary “storage tank” where the chemical breakdown of proteins begin. A temporary “storage tank” where the chemical breakdown of proteins begin. The food is mixed together with gastric juices, secretions from the stomach’s lining The food is mixed together with gastric juices, secretions from the stomach’s lining containing pepsin and hydrochloric acid. containing pepsin and hydrochloric acid.

16. Stomach As the stomach fills: As the stomach fills: stomach contract stomach contract churn the food and gastric juices together churn the food and gastric juices together This produces chyme This produces chyme a creamy, fluid mixture of food and gastric juices. a creamy, fluid mixture of food and gastric juices.

17. The passage of digested food from the digestive tract into the circulatory system. The passage of digested food from the digestive tract into the circulatory system. The small intestine is the major absorption site. The small intestine is the major absorption site.

18. Small Intestine The major part of digestion and absorption 20 to 23 feet in length Secretions from the pancreas, liver, and intestinal juices complete the chemical breakdown of all food.

19. Small Intestine Millions of fingerlike projections called villi Millions of fingerlike projections called villi Each villus contains a network of capillaries which absorb digested food particles from the small intestine. Each villus contains a network of capillaries which absorb digested food particles from the small intestine. Once food particles enter the capillaries in the villi, they are carried throughout the body by the blood. Peristalsis moves the chyme from the stomach into

20. Small Intestine Three parts to the small intestine Three parts to the small intestine Duodenum Duodenum Food enters here from the stomach Food enters here from the stomach Jejunum Jejunum The middle section of the SI The middle section of the SI Ileum Allow one way flow into the large intestine.

21. The Liver & Pancreas Liver: 2 nd largest organ in the body. Acts to clear the blood of toxins then excreting them in the bile. Bile is a yellowish-green, bitter fluid important in the breakdown of fats.

22. Liver & Pancreas The pancreas produces 3 enzymes: The pancreas produces 3 enzymes: Trypsin, which digests proteins Trypsin, which digests proteins Amylase, which digests carbohydrates Amylase, which digests carbohydrates Lipase, which digests fats Lipase, which digests fats Located in the C of the SI’s duodenum. Located in the C of the SI’s duodenum.

23. Gallbladder Storage organ for bile produced from liver Storage organ for bile produced from liver Located below the liver Located below the liver The small intestine stimulates the release of bile into the duodenum. The small intestine stimulates the release of bile into the duodenum. Not required for digestion Not required for digestion

24. Large Intestine Starts Ascending colon Starts Ascending colon Ends at the anus. Ends at the anus. A.K.A. the colon A.K.A. the colon 5 to 6 feet long 5 to 6 feet long

25. Large Intestine Unabsorbed materials: Unabsorbed materials: leave the small intestine in the form of liquid and fiber leave the small intestine in the form of liquid and fiber enter the large intestine enter the large intestine Absorbs most remaining Absorbs most remaining Water Water Vitamins Vitamins

26. The expulsion of undigested food or body wastes. The expulsion of undigested food or body wastes.

27. Elimination Harmless bacteria in the large intestine change the consistency of the undigested food into a semisolid waste, called feces Feces passes from the body through the anus Termed “bowel movement”

29. Activity: Reconstructive Surgery

30. Lifestyle & Dietary Factors Eat at least 3 servings from a variety of fruits and vegetables to avoid constipation Eat at least 3 servings from a variety of fruits and vegetables to avoid constipation Practice good hand washing hygiene Practice good hand washing hygiene Throw food away after it falls on the floor Throw food away after it falls on the floor Wash all foods before eating Wash all foods before eating Decrease caffeine consumption Decrease caffeine consumption

31. Medications Some over the counter drugs that will help aid in the relief of constipation and diarrhea. Some over the counter drugs that will help aid in the relief of constipation and diarrhea. Diarrhea Diarrhea a. Imodium AD b. Pepto-Bismol Constipation Constipation a. Citrucel b. Ex-Lax

32. Stats of Constipation & Diarrhea

33. Create your own digestive tract Each group will be representing a different part the digestive tract Each group will be representing a different part the digestive tract The group will stand in front of the class and present the pathway of food from ingestion to excretion The group will stand in front of the class and present the pathway of food from ingestion to excretion Each person will state the organ they are and their function Each person will state the organ they are and their function Be creative and have fun with the activity Be creative and have fun with the activity