Digestion Flashcards
Digestion
The process of breaking down food into small enough molecules that can be absorbed through the intestinal wall
Absorption
The process of moving nutrients from the gastrointestinal tract into the bloodstream
Transport
The process of moving absorbed nutrients throughout the body through the circulatory and lymph systems
Elimination
The excretion of undigested and unabsorbed food through the feces
Sphincters
What allows food to pass from one organ to the next
Mouth
Mastication, tears and shreds and mixes food with saliva
Epiglottis
Prevents the bolus from flowing back into the trachea
Stomach
Mixes and churns food with acid, enzymes and gastric fluids into a liquid called chyme.
Small intestines
Secretes digestive enzymes and absorbs nutrients
Large intestine
Reabsorbs salts and water, compacts unwanted waste to be stored in the rectum
What is absorbed in the large intestines?
Water
Sodium
Potassium
Chloride absorption
Final stage of defecation is influenced by
Age Diet Prescription medications Health Abdominal muscle tone
Liver
Produces protein
Manufactures bile salts that digest fats
Removes and degrades toxins and excess hormones
Gallbladder
Receives bile from common hepatic duct
Releases bile into small intestines via common bile duct
Pancreas
Releases hormones to maintain blood glucose
Secretes digestive enzymes into the small intestine
Primary contractions
Peristalsis
Segmentation
Peristalsis
Squeezes food through the GI tract
Segmentation
Shifts food back and forth along the GI tract
Passive diffusion
Nutrients move from high concentration to low concentration
Facilitated diffusion
Nutrients move from high concentration to low concentration with the help of a carrier protein
Active transport
Nutrients move from low concentration to high concentration with help of a carrier protein, energy is required
Endocytosis
Cell forms a vesicle to surround and engulf a nutrient
Entergastrones
Influence GI motility, stomach emptying, gallbladder contraction, intestinal absorption and hunger.
I.e., gastrin, secretin
Hormones
Regulate digestion by controlling:
- The release or gastric and pancreatic secretions
- Peristalsis
- Enzyne activity
Ghrelin and peptide YY communicate with the nervous system to
Help decide when you eat and when to stop eating
