Digestive System #1 Flashcards
(16 cards)
Functions of the Digestive System
- Ingestion: taking food into the body
- Propulsion: moving food along the tract
- Digest: breakdown nutrients into smaller particles (polymer-> monomers)
- Absorption; of nutrients in the GI tract into the blood stream or lymphatic system
- Defection: eliminating indigestible substances (fiber or cellulose)
Peristalsis
wavelike contractions
Breakdown of nutrients
- example: Rice
Rice; Starch > glucose molecules
Chicken; protein > amino acids
Fat; triglyceride > fatty acids/glycerol
Types of Digestions
- Mechanical Digestion
- Chemical Digestion
Mechanical Digestion
Physically breaking food down
- ex: chewing
Chemical Digestion
enzymes; specific proteins, sensitive to pH
Digestive Tract Anatomy
Mouth > pharynx > esophagus > [cardia sphincter] > stomach > [pyloric sphincter] > small intestines > large intestine > sigmoid colon > rectum > anal canal
Small intestine anatomy
- Duodenum (connects the stomach to SI)
- Jejunum (middle section of the SI)
- Ileum (bottom part of the SI, connects to the cecum of the LI)
Involuntary and voluntary parts of the Digestive Tract
- Involuntary; smooth muscle of the Large intestines
- Voluntary; skeletal muscle of the external anal sphincter
Digestive Organs
- Liver
- Gall bladder
- Pancreas
Liver:
aka “hepato”, located in the upper right quadrant of the abdominal cavity + 4 lobes
- produces bile (through the hepatic ducts): bile is an emulsifier by mixing fat and water together
- detoxififes blood, alcohol, drugs
- stores Iron, Vit. A,D,E,K
- stores glycogen (stored carbohydrates)
- synthesis Albumins + Fibrinogen (blood clotting)
- urea (amino acids for energy) synthesis
- produces Lipoproteins, LDLs/ADLs
Issues with the Liver
- conditions
- Hepatitis: inflammation of the liver due to a virus
- Hep A; from sewage, contaminated water
- Hep B; from blood and sexual contact - Cirrhosis: chronic disease
- fatty, fibrosis liver causing it to die
- due to alcohol abuse - Jaundice: yellow pigment to the skin and eyes
- due to damaged liver
Gall Bladder:
aka “cholecyst”, beneath the liver (underside)
- function is to store bile
- has the cystic duct
- can be removed; called Cholecystectomy
Issues with the Gallbladder
- Gall Stones: made up of cholesterol + salts
- painful and blocks the cystic duct
Pancreas:
- has the pancreatic duct
- purpose is to secrete many enzymes and bicarbonate (HCO3-)
- secretion happens at the common bile duct
- secretes digestive enzymes; sucrase, maltase, peptidase, lipase
- Produces sodium bicarbonate: acts an antacid to neutralize the HCI from the acid
Pathway of enzyme secretion of the Pancreas
secretion happens at the hepatic duct and cystic duct forming the ‘common bile duct’
- then go through the hepatopancreatic sphincter then to the -> duedenum
