Anatomy Chapter 10.2 (Digestion) Flashcards
List how food goes in upper area of digestive system
Mouth - salivary glands + teeth - pharynx - epiglottis - esophagus
List of how food goes in lower area of digestive system
Liver - gallbladder - esophageal sphincter (entracne to the stomach) - stomach - small intestine (duodenum, jejunum, ileum) - large intestine (cecum, colon, rectum), appendix, anus
Function of salivary glands?
- Aid in chemical digestion
- Contains enzyme called amylase (breaks food to simple sugar)
- Dissolves water-soluble food particles
Function of teeth?
- Aid in mechanical digestion
- Grind food to make it smaller
What is bolus?
Food that is smoothed into a soft mass
Function of the epiglottis?
Valve that prevents food from going down from going down to the lungs
Function of esophagus?
Hollow muscular food that transports food down to the stomach
How does food go down the esophagus?
Peristalsis - wave like muscular contractions
What is the muscle that controls the entrance to the stomach?
- Esophageal sphincter
- Normally closed to prevent acid from stomach to go back up the esophagus
Function of the stomach?
- Walls are folded allowing stomach to expand after meal
- Lined with millions of gastric glands that secrete gastric juice
- Mucus coats walls of stomach to protect from strong acidic gastric juice
What is gastric juice?
- Hydrochloric acid, salts, enzymes, water, mucus
What is chyme?
Liquid produced in stomach made from digested food and gastric juice
How many layers does the stomach have?
Three
Function of the three layers?
Contract and relax to make chyme
What muscle is at the lower end of the stomach?
Pyloric sphincter
Function of pyloric sphincter?
Muscular valve that keeps food in the stomach
Three methods why stomach does not digest proteins in the stomach
- Little gastric juice is secreted until food is present
- Stomach cells secrete mucus
- Stomach produces pepsin
What is pepsin?
- Digests protein
- Hydrolyzes proteins to yield polypeptides
Function of small intestine?
- Nutrients are broken down into their component molecules
- Nutrients are absorbed through membranes that line the small intestine
Where is the duodenum?
First part of the small intestine
Function of villi?
- Folds on the wall of the small intestine
- Receives discharged substance from pancreas and gallbladder
Function of jejunum?
- Contains more folds than duodenum
- Breaks down remaining carbohydrates and proteins so it can be absorbed in bloodstream
- 2.5m long
Function of ileum?
- Fewer/smaller villi
- Absorb nutrients
- Push undigested material into large intestine
Function of pancreas?
- Secretes pancreatic fluid
- Contains numerous enzymes that chemically digest carbs, lipids, proteins
- Contains bicarbonate (alters pH of chyme
Function of liver?
Secretes bile
What is bile?
- Made up of bile pigment and salts
- Waste products from the liver’s destruction of old red blood cells
- Eliminated through feces
Function of gallbladder?
Stores bile between meals
Function of large intestine?
Absorb water for alimentary canal