Digestive System Anatomy Beginning the system Mouth Teeth

Digestive System Anatomy

Beginning the system • Mouth – Teeth – Tongue – Salivary glands • • Pharynx Esophagus Stomach Small Intestine – Liver and Pancreas • Large intestine

The Mouth • Teeth: – The teeth help grind up the food. – Physical breakdown of food. – Function of various teeth • Incisors: • Canines: • Molars:

The Mouth • Salivary Glands: – Produce saliva • Functions of saliva – Humidifies the food – Begins chemical breakdown of starches • Possible problems – Tumors/ Cancer – Infections

The Mouth • Tongue: – Deglutition – Taste buds – Prepares the bolus for the esophagus

The Pharynx • Part shared by both the respiratory and digestive systems • Links the mouth to the esophagus. • What about choking?

Continuing down the Tract • Mouth • Pharynx • Esophagus – Cardiac Sphincter • Stomach • Small Intestine – Liver and Pancreas • Large intestine

The esophagus • Where peristalsis occurs: – Rhythmic muscle contractions that move food through the digestive tract. – Basically squeezes the food into the stomach – Last about 9 minutes

The cardiac Sphincter • Controls the amount of food let in • Prevents the stomach acid from rising and burning the tissues of the esophagus • Basically the sphincter is a bouncer • It is a type of valve • Plays a major role in “burping”

The autopsy • Mouth • Esophagus • Stomach – Gastric Glands – Pyloric Sphincter • Liver and Pancreas • Small Intestine • Large intestine

The Stomach • Mechanical and Chemical Transformations • Mechanical transformations – It churns (mixes the food with the stomach acids and breakdown the food)

The Gastric Glands • Chemical Secretions of the stomach – Pepsin • Breakdown of proteins into shorter chains of amino acids – Stomach acid • About 1 - 4 on the p. H scale • Kills almost all the bacteria fund in your food – Mucin • Protective coating of the stomach

• What is an Ulcer – An ulcer occurs when the gastric glands either produce • too much HCl or • Too little mucin • So basically an ulcer is created when your stomach acid is burning through your stomach lining • Often occurs if someone is really stressed

So far… • The food is masticated, humidified and turns into a bolus through deglutition. • This bolus gets pushes down the esophagus via peristalsis. • It passes through the cardiac sphincter and goes into the stomach. • There it is churned and mixes with various stomach acids and turns into a gucky liquid called chyme.

Out of the stomach • The pyloric sphinter controls the exit of the chyme from the stomach. • The stomach muscles will contract (every 5 minutes) releasing chyme into the small intestine.