Biochem 32: Digestion And Transport Of Dietary Lipids

Front 1

triacylgrlycerol structure

Back 1

glycerol backbone to which three fatty acids are attached

Front 2

main route for triacylglycerol digestion

Back 2

hydrolysis to fatty acids and 2-monoacylglycerol in the lumen of the intestines

Front 3

CCK

Back 3

stimulates gall bladder contraction

Front 4

what is the major component of human milk that differs it from cow milk

Back 4

long chain poly unsaturated fats important for brain development

Front 5

how is milk still absorbed in the newborn eben with a low concentration of pancreatic lipase and bile salts

Back 5

lingual and gastric lipases make up for it, also get lipases from breast milk

Front 6

what happens with hemolytic anemias and gall bladder

Back 6

increase of water unsoluble bilirubin in liver, goes to gall bladder, crashes out because not soluble, forms stones

Front 7

two dietary enzymes that digest triacylglycerols in the intestines

Back 7

pancreatic lipase and colipase

Front 8

why does pancreatitis manifest with increased lipase levels

Back 8

irritation and inflammation of pancreatic cells that stimulates secretion

Front 9

function of colipase

Back 9

allows lipases to break down triacylglycerols by relieving bile salts

Front 10

pancreatic lipase function

Back 10

hydrolyze fatty acids

Front 11

what are triacylglycerols broken down into in the small intestine before absorption

Back 11

fatty acids and 2-monoacylglycerols

Front 12

where are bile salts reabsorbed

Back 12

ileum

Front 13

what is unique about short and medium chain fatty acids

Back 13

they do not need bile salts to be absorbed and are consequently absorbed into portal blood circulation directly instead of the lymph system

Front 14

fat soluble vitamin deficiency

Back 14

vitamins ADEK are absorbed from micelles, prolonged obstruction of the bile duct can lead to shortages of these in the body

Front 15

what happens to fatty acids and 2-monoacylglycerols after absorption in intestinal epithelial cells

Back 15

condensed in smooth ER to form triacylglycerols again

Front 16

fatty acids to what precursor

Back 16

fatty acid to fatty co enzyme A

Front 17

how is 2-monoglycerol formed into triacylgrlycerol

Back 17

fatty acyl coenzyme a + 2 monoacylglycerol forms diacylglycerol, another one added on makes triacylglycerol

Front 18

why are triacyllglycerols transported in lipoproteins

Back 18

because they are insoluble in water, if directly put into the blood stream, they would coalesce in vessels

Front 19

triacylglycerol transport mechanism

Back 19

chylomicrons

Front 20

what are also contained in chylomicrons

Back 20

cholesterol and fat-soluble vitamins

Front 21

what makes up chylomicrons

Back 21

lipoproteins

Front 22

what makes up lipoproteins

Back 22

apo proteins

Front 23

major apoprotein associated with chylomicrons

Back 23

B48

Front 24

nascent chylomicrons

Back 24

chylomicrons that have not accepted proteins from HDLs

Front 25

mature chylomicrons

Back 25

chylomicrons that have begun to accept proteins from HDLs

Front 26

why are chylomicrons the least dense of all the lipoproteins

Back 26

high triacylglycerol content

Front 27

What proteins does HDL transfer to nascent chylomicrons

Back 27

Apo CII and ApoE

Front 28

what is the function of Apo CII

Back 28

receptor for lipoprotein lipase that serves to digest triacylglycerols in chylomicrons and VLDL in blood

Front 29

what is the function of Apo E

Back 29

allows for endocytosis in the liver for digestion by lysosomes

Front 30

what enzyme can be inhibited in order to prevent the absorption of fats

Back 30

pancreatic lipase

Front 31

fate of chylomicron after releasing triacylglycerides

Back 31

degraded by LPL attached to the proteoglycans in the basement membrane

Front 32

why is adipose LPL more active after a meal than muscle LPL

Back 32

higher Km

Front 33

how is LPL upregulated post meal

Back 33

after eating when insulin levels rise, this causes an upregulation of adipose LPL, so when triacylglyceride levels rise they can be stored in adipose tissue

Front 34

fate of triacylglycerols once stored

Back 34

can also be used for energy

Front 35

how do muscles use lipoproteins for energy

Back 35

they have a lower Km for triacylglycerols than adipose tissue so they can obtain fatty acids from blood lipoproteins when needed

Front 36

chylomicron remnant

Back 36

part of the chylomicron that is left over after LPL action

Front 37

fate of chylomicron remnant

Back 37

apoE protein recognized by the liver and endocytosed for breakdown

Front 38

fun fact: heparin can unbind LPL from vascular endothelium and increase triglyceride content in the blood

Back 38

bringing sexy back

Front 39

microsomal triglyceride transfer protein

Back 39

used for the synthesis of chylomicrons for transferring triacylglycerides across membranes

Front 40

abetalipoproteinemia

Back 40

lack of triglyceride transfer activity