Term
describe the solubility of lipids |
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Definition
hydrophobic, non-polar, water insoluble |
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Term
what does the solubility of lipids cause the molecules to do |
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Definition
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Term
how can you dissolve lipids |
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Definition
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Term
what are the major functions of lipids |
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Definition
provide hydrophobic barriers for cell membranes and subcellular compartments, source of energy |
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Term
what are the minor functions of lipids |
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Definition
coenzyme or regulatory, regulating homeostasis |
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Term
what lipids have coenzyme functions |
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Definition
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Term
what lipids have functions in regulation of homeostasis |
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Definition
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Term
what has increased intake in saturated FA and cholesterol been shown to cause risk of, what form of fat does not |
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Definition
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Term
what is the optimal pH for acid lipase |
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Definition
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Term
what are the enzymes in the stomach that digest lipids |
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Definition
acid lipase, lingual lipase, gastric lipase |
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Term
what is an example of something that acid lipase digests |
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Definition
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Term
what enzyme is important in neonates for milk digestion |
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Definition
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Term
what does acid lipase target |
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Definition
short and medium chain FA (<12 C) |
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Term
where is lingual lipase secreted |
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Definition
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Term
where is gastric lipase secreted |
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Definition
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Term
in general what processes emulsify dietary lipids |
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Definition
complimentary actions: mechanical agitation and secretion of bile salts |
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Term
what causes mechanical digestion, what does it accomplish |
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Definition
peristalsis increases surface area of lipid droplets |
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Term
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Definition
make smaller particles, detergent stablizes particles so they dont stick back together |
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Term
where are bile salts made |
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Definition
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Term
where are bile salts stored |
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Definition
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Term
where are bile salts secreted |
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Definition
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Term
what do proteolytic enzymes in the small intestines digest |
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Definition
TAG, cholesterol esters, phospholipids |
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Term
what digests TAGs in the small intestine |
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Definition
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Term
what does pancreatic lipase cleave TAGs into |
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Definition
2-monoacylglycerol and FA |
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Term
what percent of the pancreatic secretion is pancreatic lipase |
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Definition
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Term
what does pancreatic lipase need for it to work |
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Definition
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Term
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Definition
binds pancreatic lipase at a 1:1 ratio moving it to aqueous barrer where inhibitor bile acids are present so enzymes can get to the TAG |
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Term
ih what form is most dietary cholesterol |
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Definition
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Term
what digests cholesterol esters in the small intestines |
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Definition
pancreatic cholesterol esterase |
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Term
what does pancreatic cholesterol esterase turn cholesterol esters into |
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Definition
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Term
what activates pancreatic cholesterol esterase |
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Definition
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Term
in general how are phosphilipids digested |
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Definition
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Term
what is the process of phospholipid digestion |
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Definition
1. phospholipase A2 removes FA from position 2 makes lysophorpholipid and FA 2. lisophospholipase removes FA from position one making glycerophosphoryl and FA 3. glycerylphosphorly base is absorbed, digested, or excreted |
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Term
what conteols pancreatic enzymes |
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Definition
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Term
what is CCK secreted from |
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Definition
mucosal cells of lower duodenum and jejunum |
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Term
what is CCK released in response to |
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Definition
lipids, partially digested proteins |
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Term
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Definition
contraction of gall bladder releasing bile salts, phospholipids, free cholesterol. exocrine cells of pancreas to secrete hydrolytic enzymes, decreases gastric motility, reducing release of gastric contents into the small intestines |
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Term
what type of hormone is secretin |
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Definition
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Term
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Definition
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Term
what does secretin respond to |
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Definition
low pH of chime entering intestine |
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Term
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Definition
bicarbonate release from liver and pancreas, gives appropirate pH for enzyme function |
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Term
after being digested what happens to the lipid particles |
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Definition
they form into micelles along with soluble vitamins and bile salts, micelles go to brush border of the membrane of enterocytes and are absorbed |
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Term
what does lipid digestion in the small intestines generate in the end |
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Definition
Fa, cholesterol, 2-monoacylglycerol |
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Term
how do long chain fatty acids get absorbed into brush border |
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Definition
broken down and put into micelles |
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Term
how do short and medium chain fatty acids get absorbed into brush border |
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Definition
they can go right through |
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Term
once in the enterocytes, what happens to long chain FA |
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Definition
converted to acyl-Coa at the ER |
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Term
once in the enterocytes, what happens to 2-monoacylglycerol, what helps |
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Definition
TAG synthase sequentially adds FA using acyltransferase activities |
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Term
once in the enterocytes, what happens to lysophospholipids |
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Definition
reacylated by acyltransferases to form phospholipids |
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Term
once in the enterocytes, what happens to cholesterol |
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Definition
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Term
once in the enterocytes, what happens to short and medium chain FA |
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Definition
not activated, released into portal circulation and carried by serum albumin |
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Term
what needs to happen to TAG and cholesterol esters before the can leave the enterocyte |
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Definition
need to be packaged into chylomicrons |
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Term
what is a chylomicron made of |
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Definition
TAG and cholesterol esters with a layer of phospholipids, cholesterol, and Apo B48 around the outside |
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Term
where are chylomicrons made |
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Definition
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Term
once made, what happens to the chylomicron |
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Definition
exocytosed into the lacteal making the lumph chyle |
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Term
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Definition
lymph capillary in the SI villi |
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Term
what happens when the chylomicron makes chylo |
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Definition
it is passed into the lymphatic system to thoracic duct to left subclavian then blood |
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Term
what happens to a chylomicron once it reaches a tissue |
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Definition
lipoprotein lipase degrades TAG into FA and glycerol |
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Term
where is lipoprotein lipase secreted |
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Definition
mostly muscle and adipose but also heart, lung, kidney, liver |
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Term
what does lipoprotein lipase associate with |
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Definition
lumen endothelial cells of capillary bed |
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Term
what happens for FA in circulation |
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Definition
they are usually taken up immediatly by adjacent muscle or adipose if they dont, they will circulate on albumin until they are |
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Term
what happens to glycerol after being released into blood |
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Definition
it is taken up by liver and used to make glycerol-3-phosphate for glycolysis or gluconeogenesis |
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Term
what remains after the contents of a chylomicron are used by the tissues |
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Definition
phospholipids, cholesterol esters, apolipoproteins, fat soluble vitamins, TAG |
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Term
what happens to chylomicron reamins |
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Definition
interacti with liver cells and are endocytosed |
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Term
what happens to nitrogenous bases and phospholipids associated with FA transport to tissues |
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Definition
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Term
how can you tell there is lipid malabsorption |
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Definition
fat soluble vitamins and essential fatty acids in excretion |
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Term
what diseases involve lipid malabsorption |
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Definition
cystic fibrosis and shortened bowl |
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Term
what type of inheritence is cystic fibrosis |
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Definition
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Term
what is mutated in cystic fibrosis, what does this cause |
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Definition
CL ion channels CFTR that hydrate mucous in secretory ducts of pancreas mutations lead to viscous mucous tha blocks pancreatic enzymes needed for lipid digestion in si |
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Term
what are the symptoms, other than lipid malabsorption of cystic fibrosis related to lipids |
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Definition
delayed growth, energy deficient |
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Term
how is cystic fibrosis treated |
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Definition
with enzyme replacement and fat soluble vitamin supplements |
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