upper gi Flashcards
Appetite controlled by
hypothalamus
Stimulated by hypoglycemia, empty stomach, decreased body temperature, brain input
Deglutition: swallowing
Includes mouth, pharynx, and esophagus
Absorption
occurs in the small intestine (villi)
Digestion is completed in the
small intestine.
Carbohydrates
Digestion starts in
mouth
Followed by digestion in the small intestine
Proteins
Digestion starts in
stomach, continues in small intestine
Lipids
Emulsified by
bile prior to chemical breakdown
Action of enzymes form monoglycerides and free fatty acids
Formation of chylomicrons
Fat-soluble vitamins
Vitamins A, D, E, K
Absorbed with fats
Water-soluble vitamins
Vitamins B and C—diffuse into blood
Electrolytes
Absorbed by active transport or diffusion
Drugs are primarily absorbed in the
intestine.
Various transport mechanisms
Some (e.g., aspirin) absorbed in the stomach
Gastric Secretion Phases
Cephalic (nervous)
–Secretion of hydrogen chloride (HCL), pepsinogen, mucus
Gastric (hormonal and nervous)
–Secretion of gastric hormone from antrum to stimulate gastric secretions
Intestinal (hormonal)
–Acidic chyme (pH <2): release of secretin, gastric inhibitory polypeptide, cholecystokinin
Chyme (pH >3): release of duodenal gastrin
Parasympathetic nervous system (PNS)
Primarily through vagus nerve (cranial nerve
[CN] X)
Increased motility
Increased secretions
Sympathetic nervous system (SNS)
Stimulated by factors such as fear, anger
Inhibits gastrointestinal activity
Causes vasoconstriction
Reduced secretions and regeneration of epithelial cells
which cranial nerves
Facial (CN VII) and glossopharyngeal (CN IX) nerves
Stomach empties within
2 to 6 hours after meal.
Gastrin
Secreted by mucosal cells (stomach) in response to distention of stomach or partially digested substances
Increases gastric motility, relaxes pyloric and ileocecal sphincters—promotes stomach emptying
Histamine
Increased secretion of hydrochloric acid
Secretin
Decreases gastric secretions
Cholecystokinin
Inhibits gastric emptying; stimulates contraction of gallbladder
Elimination
mainly happens in the large intestine
Haustral churning
what does pepsin breakdown
proteins
stomach forms
chyme
where does vit k synthesis happen?
in large intestine
if you throw up too much
alkalosis .
this aint important
and i might be wrong