*Test Five Flashcards
Tania Coli muscles
causes “Mass Peristalsis”, forces colon contents into rectum (roughly every 24 hours)
microvilli
tiny folds in the membrane of the epithelial cells lining the small intestine
Acini cells
- produce pancreatic juiceput HCO3- into pancreatic juice (which becomes sodium bicarbonate)
- neutralizing acidic chyme entering small intestines
- puts H+ into blood to correct alkaline nature
- make the 8 pancreatic enzymes
defecation reflex
controls elimination of solid waste
8 pancreatic enzymes and what they break down into
- pancreatic amylase - disacchardies
- pancreatic lipase - fats
- ribonuclease - nucleic acids
- deoxyribonuclease - nucleic acids
- trypsinogen (inactive) - converted by enzyme enterokinase into trypsin
- TRYPSIN THEN ACTIVATES…
- chymotrypsin - proteins
- elastase - proteins
- carboxypepsidase - proteins
- TRYPSIN THEN ACTIVATES…
4 major digestive hormones
- gastrin- stomach, stimulates HCl, enzymes, and peristalsis
- GIP (gastric inhibitory protein)- small intestine, stimulates insulin release, stops HCl/enzyme production
- sectretin- small intestine, stimulates pancreatic juice release (neutralizes HCl)
- cholecystokinin- stimulates release of bile from the gall bladder
carb enzymes
the amylases
4 specific food groups and what they break down into
- carbs - saccharides like sugar
- proteins - amino acids
- lipids - fatty acids
- nucleic acids - nucleotides
aminopepsidase
for proteins
Islets of Langerhans
produce two pancreatic hormones (insulin and glucagon)
list the materials that hepatocytes make
- bile- emulsifies fats, keeps them from clumping together
- converts heme to bilirubin (enters bile, gives feces its color)
- plasma proteins
- albumin- controls osmosis, failure = ascites
- alpha/beta globulins
- compliment proteins- (low = prone to bleeding)
- prothrombin- bruising
- fibrinogen- blood clotting
transanimation
hepatocytes can convert one amino acid into another
2 kinds of stomach cells
- chief cells- secrete inactie enzyme pepsinogen
- parietal cells- contain enzyme carbonic anhydrase, also run CO2 + H2O ⇔ HCO3- + H+ reaction, put H+ into stomach to make HCl, put HCO3- into blood (alkaline, neurtralizes H+)
chief cells
secrete inactive pepsinogen
Plexus of Auerbach
neurons that stimulate peristalsis in muscularis layer
chyme
the thin mixed liquid that exits the stomach
describe protein digestion
- stomach
- HCl denatures proteins, converts pepsinogen into pepsin
- pepsin cuts proteins into smaller strings (peptides)
- small intestine
- enterokinase converts trypsinogen into trypsin
- trypsin activates elastase and chymotrypsin (cuts small protein strings even smaller)
- trypsin also activates carboxypeptidase with the brush border enzyme aminopeptidase, the 2 cut individual amino acids off the strings from the carboxyl and amino acids
acid reflux disease
caused by a defective cardiac sphincter, acid rises into esophagus, results in damage to esophageal wall (as there is no protective mucus)
enterokinase
activates trypsinogen
2 digestive system cells that run the carbonic anhydrase reaction, where they are, and what their purpose is
- parietal cells- stomach, contain carbonic anhydrase and run reaction
- puts H+ into stomach (makes HCl)
- puts HCO3- into blood (alkaline, neutralizes H+)
- acini cells- produce pancreatic juice
- put HCO3- into pancreatic juice, neutralizes acidic chyme entering small intestine
- puts H+ into blood to correct its alkaline (pH 7.35-7.45) nature
segmentation
muscles of the small intestine break chyme into section and move it along
Plexus of Meissner
neurons for nucus glands (food lubrication) in submucosa layer
esophageal hiatus
where the esophagus pierces the diaphragm
deanimation
excess protein? clip off amino group, turn the rest into ATP
brush border cells
line microvilli, make enzymes (enterokinase (which activates trypsinogen), aminopepsidase (for proteins), and carb enzymes (the amylases))
chylomicrons
golgi body of brush border cells package lipids for export in these structures (which go to lacteals)
mastication
chewing
secretion
depositing of enzymes into the GI tract (a key function of the pancreas)
describe lipid digestion
- (majority is in small intestine)
- lipids are big, made of glycerol and 3 fatty acid tails, hydrophobic
- process
- chyme enters small intestine with bif fat globules
- segmentation breaks big globules up into tiny ones
- bile emulsifies the fats as micelles
- pancreatic lipase pulls off the first and third fatty acid tails
- brush border cells absorb these small pieces, their smooth ER then reassembling the fat inside the cell
- golgi apparatus of brush border cells packages lipids for export in structures called chylomicrons (which go to lacteals)
insulin
lowers blood sugar, made by beta cells
Nucleic acids break down into what?
nucleotides
deglutination
swallowing
lysozyme
enzyme in saliva that destroys bacterial membranes
peristalsis
“alternating contraction and relaxation of smooth muscles in the walls of the GI tract to propel food”
sinusoids
- hepatic arteries and heptal portal veins run together into these large spaces in liver
- lined with kupffer cells and hepatocytes
Carbs break down into what?
saccharides like glucose
Proteins break down i to what?
amino acids
kupffer cells
- “major phagocytic cells of the liver”, destroy old RBCs, converts heme to bilirubin (enters bile, gives feces its color)
- not working = chronic infections and jaundice (bilirubin buildup)
parietal cells
- contain enzyme carbonic anhydrase
- also run CO2 + H2O ⇔ HCO3- + H+ reaction
- put H+ into stomach to make HCl
- put HCO3- into blood (alkaline, neutralizes H+)
ascites
when an abnormal amount of fluid collects in the abdomen (in the peritoneal space)
hepatocytes
- make bile
- store glycogen (carbs) and fat soluble vitamins (like vitamin K)
- make plasma proteins
- albumin- controls osmosis, failure = ascites
- alpha & beta globulins
- compliment proteins- low = prone to bleeding
- prothrombin- bruising
- fibrinogen- more bruising
pyloric sphincter
between stomach and small intestines
hepatic portal vein
brings deoxygenated nutrient rich blood into the liver (from small intestine)
mixing waves
mechanical action the the stomach created by peristalis, churning creates this
glucagon
raises blood sugar, made by alpha cells
illeocecal sphincter
separates small intestines from large intestines
Lipids break down into what?
fatty acids
3 things HCl does in the stomach
- kill bacteria (pH 2.2)
- denature proteins (unfold them)
- activate pepsinogen, turning it to pepsin
absorption
passage of nutrients into the blood
