Digestive System

2 Types of Digestion Mechanical – Breaks down food PHYSICALLY/MECHANICALLY Chemical – Breaks down food using CHEMICALS

The Mouth Tongue – Moves food around Incisors – Sharp – Cut food Canines – Pointed – Tear Food PreMolars/Molars – Flat – Grind Food Salivatory Glands – Produces Saliva

Mechanical or Chemical?

Mouth and Throat Pharynx – Upper portion of throat Larynx – Where throat separates from lungs and esophagus/ Voice box Trachea – Windpipe – leads to the lungs

Mouth and Throat Epiglottis – Flap that prevents food from entering lungs Esophagus – Tube connecting mouth to stomach

Esophagus Uses PERISTALISIS to MOVE food down to the stomach PERISTALISIS = CONTRACTIONS Lined with mucus – helps food travel down to stomach Sphincter is found at end of esophagus – preventing food/acid from traveling back up!

Mechanical or Chemical?

STOMACH Sloshes food around – mixing in ACIDS and ENZYMES Pepsin (enzyme) breaks down proteins Food turns into thick liquid BOTH!!! Sloshing and Grinding = Mechanical Acids and Enzymes = Chemical

Small Intestines DUODENUM (beginning) – Continues to BREAK DOWN FOOD JEJUNUM (middle section) – Nutrients are Absorbed IlEUM (end section) – Nutrients are absorbed Food moves through PERISTALSIS (contracting waves)

Support for Small Intestines Liver Stomach Gall Bladder Pancreas

Liver LARGEST ORGAN IN THE BODY!!!! Produces BILE BILE Gallbladder Breaks up fat particles Not an enzyme! Similar to soap in grease – breaks it into small bubbles of grease Sack that holds BILE Squirts bile into duodenum

Pancreas Produces enzymes Breaks down starches, proteins, and fats

Absorption in Small Intestine Villi – finger-like things that have blood vessel inside. Nutrients enter blood through VILLI

Appendix At start of Large Intestine Hypothesized that it stores extra “good” bacteria, used in severe cases of dysentery Is safe to remove

Large Intestine Water Absorption Bacteria present to further break down VITAMINS Also known as COLON

End of Large Intestine Rectum – – Waste is collected; – Compressed into solid form Anus – – Sphincter that releases waste