Chapter 24Digestive System

Digestive Processes

• Ingestion

• Movement / peristalsis

• Digestion (chemical & mechanical)

• Absorption

• Defecation

Anatomical Terms

• Peritoneum (visceral & parietal)

• Mesentery

• Falciform ligament

• Omentum (lesser & greater)

• Mesocolon

Gastric Digestion

• Zymogenic (peptic) (Chief) cells = pepsin

• Parietal (oxyntic) cells = HCl

• Mucous cells

• Enteroendocrine cells = gastrin

• Gastric lipase & rennin

Liver Function• Carbohydrate metabolism• Fat metabolism• Protein metabolism• Removal of drugs & hormones• Excretion of bile• Synthesis of bile salts• Storage of vitamins, minerals and glycogen• Phagocytosis of WBC’s and RBC’s• Activation of vitamin D• Removal of toxins (includes ammonia)• Manufactures heparin

Bile• Bile consists of water, bile salts,

cholesterol, phospholipids, bile pigments and ions.

• Bile pigment consists of iron, globin, and bilirubin (from the heme). Iron and globin are recycled some bilirubin is excreted in bile.

Pancreas

• Islets of Langerhans produce insulin and glucagon

• Acini produce pancreatic juice –– Sodium bicarbonate– Amylase– Trypsin– Lipase– Ribonuclease– Deoxyribonuclease

Intestinal Juice

• Water and mucus• Maltase, Sucrase and lactase• Peptidase• Ribonuclease• Deoxyribonuclease

Lactose intolerance = no lactase

Summary Chart on Digestion

Terms & Diseases

• Caries and plaque

• Peritonitis

• Peptic ulcers

• Appendicitis

• Tumors

• Cirrhosis

More terms

• Diverticulosis, diverticulitis, diverticulum• Hepatitis• Biliary calculi (gallstones)• Borborygmus• Cholecystitis• Cholelithiasis• Colitis• Colostomy

More Terms

• Dysphagia• Hernia• Ascites• Bruxism• Laparoscopy• Pancreatitis• Pyloric stenosis• Lithotrypsy