Digestive System

Digestive SystemHonors Biology

Alimentary CanalOne-way digestive tract through the body

Lumen of digestive tract

is externalenvironment

1-way flow ishighly effi cient

Body

Alimentarycanal

Digestive Processes

Digestive Organs

Mesentary

Peritonitis

Cadaver Midsaggital Section of Oral Structures

Oral Anatomy Anterior View

Tongue Anatomy

Taste Bud Anatomy

Salivary Glands

Cadaver ___ Gland

Tooth Anatomy

Tooth Eruption

Impacted Molar

Gingiva

Endoscope

Larynx

Esophageal Reflux

G.E.R.D. (GastroEsophageal Reflux

Disease)

Gastric Fundus

Gastritis due to Helicobacter Pylori

Gastric Diverticulum

Gastric Polyps

Gastric Carcinoma

Duodenal Mucosa

Duodenal Ulcer

Proctologist

Testing for Occult Blood

Colonoscopy

Colonoscopy Administration

Caecal Diverticula

Descending Colon

Tapeworms

Ulcerative Colitis (Sigmoid Colon & Rectum)

Rectum

Anal Hemorrhoids (Piles) Caused by Inflammation of

the Superior & Inferior Hemorrhoid Veins

Scope Comparison

Barium Enema

Colostomy& Stoma

Colostomy Bag

Peristalsis

Food is moved through the alimentary canal two ways

Segmentation

27 Year Old Male

81 Year Old Male

Gastric Anatomy

Gastric Cells

4 layers

Gall Bladder & Pancreas Empty Contents into

Duodenum

Liver & Pancreas Secretions

Liver FXN’s• Synthesizes bile (bile salts,

biliruben, & cholesterol)

• Stores glucose as glycogen

• Stores fat soluble vitamins ADEK

Gall BladderFXN• Stores bile

Pathophysiology• Gall stones – too much cholesterol or too few

bile salts resulting in cholesterol crystal accumulation

• Obstructional jaundice – bile duct becomes obstructed & bilirubin increases in blood

Gallstones

Bile Salt

PancreasFXN• Secretes basic pancreatic juice (pH 7.5-8.0)

Pancreatic Juice (p.j.)• Bicarbonate rich p.j. neutralizes HCl in the duodenum

(Stimulated by secretin when HCl enters the duodenum)

Note• Enzymes released in inactive form so they don’t digest

the pancreas

Accessory Organ Ducts & Sphincter

Water & minerals• No need f or digestion• Water absorbed by osmosis

8.5 liters/ day• Minerals absorbed by

– Active transport– Facilitated diff usion

Water & Mineral Digestion

Absorption of…Vitamins – • A,D,E,K fat soluble (diffuse into blood)• B & C water soluble (diffuse into blood)

• Electrolytes (Na+, K+, HCO3-, Cl-)

• Calcium – PTH increases ionic calcium & vitamin D aids in absorption

Lipid Emulsification

Carbohydrate Digestion

Na/K Symport

Protein Digestion

Small Intestine

Large Intestine with Mesentery

Cecum

Feces may indicate health issues• Motility / timing• Diarrhea• Constipation

• Color / consistency• Gray = lack of bile• Black/tarry = bleeding (upper)

• Black = PeptoBismol• Red = bleeding (lower)