1. First Steps of Digestion

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3. How Important Are Teeth? Teeth provide surface for mechanical digestion. Molarsgrinding Incisorbiting Caninepiercing Bicuspidgrinding Tongue Keeps food in place Push bolus back in mouth

4. Digestion In The Mouth: Our teeth break down food into physically smaller pieces that can be acted on by digestive enzymes. The first enzyme that the food encounters in our mouth is called salivary amylase.

5. Salivary Amylase: Salivary amylase is released by our salivary glands and is the most abundant enzyme in our saliva. Salivary amylase begins the digestion of carbohydrates.

6. Digestion of Starch: Salivary amylase in the mouth begins the digestion of starch. Starch Salivary Amylase Disaccharides

7. Digestion of Starch: The breakdown of starch continues in the small intestine. Pancreatin (a mixture of several digestive enzymes produced by the pancreas) – Amylase – Lipase – Protease In the small intestine the disaccharides are further broken down into monosaccharaides.

8. Digestion of Starch: Starch Salivary Amylase Disaccharides Pancreatic Amylase monosaccharaides

9. Digestion In The Mouth: Your saliva also contains an enzyme called Lysozyme. – Fights infection by breaking down the cell walls of bacteria that may come in contact with food.

10. Pharynx and Epiglottis Once food is chewed it moves to the back of the throat- this area is called the pharynx.

11. Pharynx and Epiglottis The epiglottis is a flap that is made of elastic cartilage tissue. The epiglottis prevents food from going down your trachea. – Allows the passage of air to the lungs.

12. Moving on….. The food that has been mechanically digested by the teeth and that has begun chemical digestion by salivary amylase is now called a bolus. The bolus enters the esophagus from the pharynx.