1. Warm Up: If a solution has a pH of 4 it is_________

2. Digestive System (Gastrointestinal Tract)

3. Digestion
Process of breaking down food into smaller forms which can be absorbed or excreted

4. Intracellular digestion: (unicellular) digestion occurs in vacoules inside the cell
Extracellular digestion: (Multicellular) digestion takes place outside the body cells in organ systems

5. Ingestion: consumption of a substance by an organism
Egestion: removal of undigested food or feces from the gut (solid waste)
Excretion: removal of wastes from cell’s activities (liquid and gas waste)

6. Mouth
Has three major weapons for starting the breakdown of food so that our bodies can use it as energy:
Teeth- responsible for grinding, mashing and chewing the food (mechanical).
Tongue- main player in swallowing and has power to move and mush the food (mechanical).
Saliva- mixed with the food to help it continue its journey into the esophagus (chemical).

7. Mechanical Digestion Breaks food into smaller pieces
Surface area increases
Enzymes have more surfaces to work on and complete break down faster

8. Salivary Amylase Enzyme which breaks down carbohydrates in mouth
Carbs finish being digested in small intestine

9. Esophagus
The esophagus is like a stretchy pipe that's about 10 inches long.
It connects the mouth to the stomach
Contraction of muscles to
move the food (bolus)
through the
esophagus= peristalsis

10. Swallowing
Swallowing

11. Choking In the back of the mouth are two openings.
One is the esophagus, which leads to the stomach; food goes down this pathway.
The other is the trachea, which is the opening air must pass through to get to the lungs.
When swallowing occurs, the trachea is covered by a flap called the epiglottis, which prevents food from entering the lungs.

12. Stomach
Squeezes and churns the food mixing it with digestive juices (acids and enzymes) and forms chyme
Hydrochloric Acid

13. Proteases
Enzymes which break down proteins into amino acids are located in the stomach

14. Ulcers small erosion (hole) in the gastrointestinal tract
The direct cause of peptic ulcers is the destruction of the gastric mucosal lining of the stomach by hydrochloric acid
Infection with the bacterium Helicobacter pylori is thought to play an important role in causing both gastric ulcers

15. Acid Reflux
Acid reflux occurs when the stomach churns up acid or refluxes it into the esophagus, causing a burning sensation in the chest or throat.
Too much acid can push back through a valve between the stomach and the esophagus

16. Small Intestine Named for small diameter 20 to 25 feet long
As the thick liquid paste travels through your small intestine, the nutrients (vitamins, minerals, proteins, carbohydrates and fats) from the food can finally pass through the wall of the small intestine into your blood

17. Villi in small intestine
Increase
Surface
Area
For
Absorption
Most chemical
Digestion
Occurs in SI

18. Emulsification of Fats
Lipases break down smaller particles into glycerol and fatty acids

19. Accessory Glands
Pancreas, the liver and the gallbladder help by sending different juices to the first part of the small intestine.
The pancreas makes juices that help the body digest fats and protein.
A juice from the liver called bile helps to absorb fats into the bloodstream.
The gallbladder is like a warehouse for this bile, holding onto extra amounts of it when the body needs it.

21. Liver First place that the nutrients from food go.
Processes the nutrients by filtering out any harmful substances or wastes.

22. Cirrhosis Causes Alcoholic liver disease. Chronic hepatitis B,C, D
Autoimmune
Inherited disease

23. Gall bladder
Stores bile
Buildups of bile harden=
gallstones

24. Large Intestine ~ 5 feet long
Most of the water that is left in the liquid mix is absorbed into the blood.
As the water leaves the mix, the waste that's left gets harder as it moves along, until it becomes a solid.
Waste then collects in the rectum at the end of the large intestine and finally leaves the body through an opening called the anus.

25. Roughage Indigestible portion of plant foods
Also known as dietary fiber
Keeps digestive system functioning properly because it moves food along

26. Appendix

27. Colon absorbs too much water and the feces are hard= constipation
Colon absorbs too little water and feces are soft= diarrhea

28. Animated Guide to the Digestive System

29. How does your body digest food?
Nutrition

30. MovieSource: The Digestive System

31. Digestive System Game