The Digestive System Oral cavity Pharynx Liver Gall

The Digestive System Oral cavity Pharynx Liver Gall Bladder Esophagus Stomach Pancreas Large Intestine Small Intestine

• Function: Break down food into molecules that can used by cells • Enzymes, acids, hormones, bile aid in breakdown • Sphincters (ring of muscle) separate sections • Nutrients passed into the circulatory system to be distributed in the blood Click pic to play

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Oral cavity

• Mechanical digestion: Teeth grind food • Chemical digestions: Saliva (amylase) begins to breakdown starches • Bolus is created (ball of chewed & moistened food)

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Pharynx

• Epiglottis seals off the trachea • Bolus pushed down the esophagus by the tongue

Esophagus

• Connects mouth with stomach • Peristalsis: Muscular movement pushes food along – Bolus pushed down the esophagus by muscles Click pic to play

Stomach

Click pic to play • Function: Prepares food for absorption • Chemical digestion – Pepsin (enzyme) digests proteins – Stomach acids mix • Mechanical digestion – Muscles contract to churn the bolus (~4 hours) • Chyme created: pastelike mixture of food, enzymes, acids • Peristalsis pushes chyme through sphincter

Small Intestine

• Function: Absorption of nutrients • Duodenum – Chemical digestion: Enzymes from the liver, gallbladder, pancreas released to aid digestion – Mechanical digestion: Muscular contractions mix & churn the chyme • Peristalsis pushes the chyme along • Nutrients absorbed into the capillaries of the s. intestine

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Liver Gall Bladder

• Functions: – 1) Break down toxic chemicals (alcohol) – 2) Produces bile to break down fats • Gall Bladder: Stores bile until chyme moves into duodenum

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Pancreas

Click pic to play • Functions: – 1) Release enzyme into duodenum to break down starches & lipids – 2) Releases insulin into the blood (diabetes)

Large Intestine

• AKA: Colon • Peristalsis continues to push the chyme • Remaining water is absorbed from the chyme – Undigested material solidifies (feces) • Nutrients from bacteria absorbed • Feces exits the body through the rectum & anus

• The liver is labeled which letter? L • K

• The pancreas is labeled which letter? L • D

L • Which letter begins the process of chemical digestion? • L (salivary glands)

• Most nutrients are absorbed at which organ? L • E (small intestine)

• Which organ helps digest fats? L • K (liver)

Label the letters of the diagram L A = esophagus B = I don’t care C = stomach D = pancreas E = Small intestine F = Large intestine G = Rectum H = appendix I = duodenum J = gall bladder K = liver L = salivary glands