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digestive system- 6
chapter 6
Question | Answer |
---|---|
Stomach, pancreas, small intestine contains what type of gland? | Exocrine |
Stomach mixes and stores food into | chyme |
stomach begin ____ digestion | Protein |
stomach brakes down protein with what enzyme | PEPSIN |
low ph of stomach helps to | dentature proteins; kill bacteria |
4 types of cells in the stomach | chief, parietal, mucous, G-cells |
Chief (peptic) cell secretes | pepsinogen |
Parietal ( oxyntic) cell secretes | HCL |
G-cell secretes | gastrin into interstitium |
NO absorption occurs in the | stomach |
Pepsinogen (zymogen of pepsin) is activated in stomach by | low pH |
in the cell lumen.... HCL + CO2= | Carbonic acid |
H+ from Carbonic acid is diffused into cell lumen side to | lower pH of stomach |
Bicarbonate ion is expelled to the interstitial fluid to | increase pH of blood |
gastrin stimulates | parietal cells to release HCL |
Major hormones that affect stomach juice secretion | histamine, gastrin and acetylcholine |
acetylcholine | stimulates all cells to secrete |
Gastrin and histamine | stimulate HCL secretion |
small intestine has outermost layers with fingerlike projections called | villi |
the villi's apical (lumen side) surface has | microvilli |
small hairlike stuff on microvilli | brush border |
brushborder secretes enzymes that digest | carbs, proteins, nucleotides |
small intestine does | absorption and digestion |
capillary network and lymph vessel in villi | lacteal |
_____ increase SA of intestine | microvilli |
small intestine has epithelial cells called _____, that secrete mucous to lubricate intestine and protect brush border | GOBLET cells |
Small intestine secrete juices with ____ & ____ | high pH and lysozyme |
bacteria is regulated in sm intestine by | lysozyme |
Duodenum has a pH of 6 because of | the bicarbonate ion given off by the pancreas |
pancreatic enzymes include:: | trypsin, chymostrypsin, ribonuclease, deoxyribonuclease and pancreatic amylase and lipase |
all enzymes of the pancreas are released as | zymogens |
villi aka | enterocyte |
Enterokinase located in the brush border activate | trypsin |
Trypsin activates | all the other enzymes |
______ &______ degrade proteins into polypeptides | trypsin and chymotrypsin |
proteins reach the brush border as polypeptides b4 they reach the enterocyte as | AA, dipeptides, tripeptides |
enzymes within enterocyte reduce tripeptides and dipeptides into | amino acids |
enterocyte= | cells of brushborder |
pancreatic amylase (stronger than salivary amylase) digests | polysacharides into disacharide and trisacharides |
Lipase | degraded fats into monoglycerides and fatty acids with the help of bile |
BILE | made by the liver, but stored in the gallbladder; it increases SA, and emulsifies fats (but DOES NOT digest it) |
Bile Does not touch the _____ of fats | chemistry |
Large intestine is incharge of | water reabsorbtion and electrolyte absorption. It also contains E.Coli |
bacteria E.Coli has what type of relationship with the large intestine | mutualistic symbiosis |
E.coli produce | vitamin k, B12, thiamin and riboflavin |
local peptide hormones secreted by the small intestine after a mean = | secretin, CCk, gastric inhibitory peptide |
secretin, CCk, gastric inhibitory peptide | increase BL INSULIN levels especially in the presence of glucose |
HCL in the duodenum causes | secretin release |
_____ stimulates sodium bicarbonate secretion by the pancreas | secretin |
gastric inhibitory peptide | decrease stomach motility |
causes gallblader contraction and pancreatic enzyme secretion. ALSO decreases motility of stomach, allowing more time for the duodenum to digest fats | CCK |
Is bile an enzyme? | NO it is an emulsifying AGENT |
The end product of carb digestion is | glucose (carried in the BL) |
In carb absorbtion, GLUCOSE is absorbed by a ______ and carried _____ the conc. gradient of sodium | secondary active transport mechanism; down |
formation of glucose= | glycogenesis |
When BL glucose is low, ____ takes place and in the liver and glucose is returned to the blood | glucogenolysis |
In all cells except _____ &_______, glucose is transported from high conc. to low via facilliated diffusion. | enterocyte cells and renal tubule cells |
when you think of proteins think of ___ | nitrogen |
Proteins have to be degraded into _____ before being absorbed into the blood | amino acids |
PROTEINS (amino acids) are absorbed down concentration gradient by | cotransport mechamism |
Amino Acids are transported to the cell via | active or faciliated diffusion (never Passive) |
Gluconeogenesis of proteins have what byproducts? | Ammonia( nitrogen product) |
Ammonia is converted to _____ by the liver | urea |
Urea is expelled from the body by | kidney's - urine |
fats combine with what to be transported through the blood? | albumin |
fats need a carrier b/c they r insoluble. These carriers can be | albumin or lipoproteins |
lipid in plasma= | lipoprotein |
chylomicrons = | large lipoproteins |
liver receives blood from... | capillary beds of large intestines, pancreas, stomach, spleen |
liver receives blood via | hepatic portal vein |
liver moves blood to the | vena cava |
A second blood supply is given to the liver (used to oxygenate the liver) via | hepatic artery |
2 important clotting factors | prothrombin and fibrinogen |
____ is the major osmoregulatory protein in the blood | Albumin |
Group of proteins that include antibodies | Globulins |
Antibodies are made from | plasma cells |
blood storage | liver |
blood filtration | liver |
carb, fat, and protein metabolism | liver |
detoxification | liver |
vitamin storage | liver |
erythrocyte destruction | liver |
fats enter the lymph as _____ before entering the blood | chylomicrons |
The liver synthesizes | non essential AA |
Gluconeogenesis | production of glucose and glycogen from non carb precursors; OCCURS MAINLY IN LIVER |
glycogenolysis is inhibited by | insulin |
excrete wastes, maintain homeostasis, control plasma pH | KIDNEY |
urine is emptied in which kidney part? | renal pelvis |
Filtration occurs in | renal corpuscle |
reabsoprtion/ secretion occurs in | proximal tubule |
concentrates solutes in the medulla | loop of henle |
reabsorbs Na+and Ca2+ and secretes k+, HCO3-, H+ | distal tubule |
aldosterone has what affect on the distal tubule? | lowers filtrate osmularity |
distal tubule empties into | collecting duct |
ADH makes _____ more permeable to water | collecting ducts in the medulla |
amount of filtrate is related to amount of | hydrostatic pressure in the glomulerus |
descending loop of henle is | permeable to water |
ascending loop of henle is | impermeable in water |
actively transports sodium into the kidney | ascending loop of henle |
juxtaglomular apparatus monitors filtrate pressure in the | distal tubule |
actively transports sodium into the kidney | ascending loop of henle |
juxtaglomular apparatus monitors filtrate pressure in the | distal tubule |
Renin stimulates angiotensin 1, 2, 3 to stimulates | Adrenal cortex to secrete aldosterone |
aldosterone acts on distal tubule to | secrete K+, and absorb Na2+ |