1. Digestive System

3. 1. Oral Cavity Where Digestion begins
Contains several structures that help start digestion

4. 1. Oral Cavity
A. Teeth: Break down food
32 in an adult; 20 in a child

5. 1. Oral Cavity B. saliva: keep the oral cavity moist
has enzymes that break down food
Enables specific taste
Creates a normal pH
salivary glands video

6. Salivary Glands 2, 3, 4. Salivary Glands – (3 pairs)
(parotid, submandibular, and sublingual)
Function: produce saliva
salivary glands video 4 3 2

7. Tonsils
5. Tonsils: (Lymphoid tissue) -creates white blood cells (WBC) -traps and fights pathogens(virus/bacteria)
tonsil video

8. Uvula
6. Uvula – flap of tissue at the back of the mouth; prevents food from going into the nasal cavity during chewing and swallowing

9. Tongue 7. Tongue – (muscular organ)
moving food, swallowing, tasting, and speech
attached to the mouth floor by the frenulum

10. Tongue
10,000 taste buds

11. Taste Tasting experiment
Divide your sticky note into sections: A B C D 1 2 3 4
Instructions: No talking, or smelling prior to or after placing the Q-tip on your tongue

12. Taste
Tasting Experiment Results:

13. Taste article The tongue taste map is WRONG (Daily Mail)

14. Pharynx
8. Pharynx: receives air and food from nose and mouth and pushes it downward

15. Bolus
Food is chewed by teeth, mixed with saliva, and manipulated by the tongue
9. Bolus which is a ball of food mixed with saliva
Bolus Video
Bolus Video 2

16. Esophagus 10. Esophagus:(gullet: gula=throat in latin)
To carry
To eat
10. Esophagus:(gullet: gula=throat in latin)
Connects pharynx to stomach
Peristalsis: continued contraction and relation of muscles
Esophagus Video
Sphincter Video

17. Esophagus

18. Esophagus Upper Esophageal Sphincter: push food downward
Lower Esophageal Sphincter: prevents stomach acid back flow

19. Epiglottis
Epiglottis: prevents food and liquid from going into the trachea (Trap Door)

20. Create a stomach Materials: Copy paper Scissors Ruler Colors String
Create an actual size stomach
Materials:
Copy paper
Scissors
Ruler
Colors
String
Find out:
Width of the stomach
Length of the stomach
Length of the lesser curvature
Length of the greater curvature
Length of the esophagus
(create with string)