NST 103 Midterm 3 UPDATED ACTUAL
Exam Questions and CORRECT Answers
how do lipids move through the lumen of the intestine - CORRECT ANSWER - mixed
micelles
how do lipids move in enterocytes - CORRECT ANSWER - pre and nascent chylomicrons
how do lipids move through lymph - CORRECT ANSWER - modified chylomicron
how do lipids move through blood - CORRECT ANSWER - mature and remnant chylomicron
VLDL, IDL, LDL, HDL
FFA
(TAG)
how do lipids move through adipose tissue - CORRECT ANSWER - TAG
how do lipids move through other tissues - CORRECT ANSWER - cholesterol, PL's, FFA,
TAG
lipoprotein particle size biggest to smallest - CORRECT ANSWER - chylomicron, VLDL,
IDL, LDL, HDL
Chylomicrons - CORRECT ANSWER - arise solely in intestine
contain TAG and cholesteryl ester primarily from diet
,chylomicron remnant - CORRECT ANSWER - chylomicron after most of TAG has been
removed by LPL in capillaries of adipose tissue and muscle
VLDL (very low density lipoprotein) - CORRECT ANSWER - -are secreted solely by the
liver
-contain endogenously synthesized TAG
IDL (intermediate density lipoprotein) - CORRECT ANSWER - -transiently made from
VLDL in capillaries of adipose tissue and muscle
-taken up by liver or converted to LDL
LDL (low-density lipoprotein) - CORRECT ANSWER - -derived from VLDL or IDL
-contains endogenous cholesterol
HDL (High Density Lipoprotein) - CORRECT ANSWER - -important in 'reverse transport' of
cholesterol from extrahepatic tissues to liver
Apo A-1 function - CORRECT ANSWER - -activator of LCAT
-allows binding of HDL to ABCA1 for cholesterol efflux from peripheral tissues
Apo B-100 function - CORRECT ANSWER - -required for secretion of VLDL from liver
-acts as ligand of LDL receptor
Apo B-48 - CORRECT ANSWER - -made from the same gene as Apo B100 but RNA editing
(C-->U) by cytidine deaminase converts E (CAA) to UAA (stop codon)
-required for secretion of chylomicron from intestine
Apo C-II function - CORRECT ANSWER - activator of lipoprotein lipase
, Apo E function - CORRECT ANSWER - acts as ligand of LDL receptor
FFA ______ over the course of starvation - CORRECT ANSWER - increase
TAG ________ over the course of starvation - CORRECT ANSWER - decrease
KB ______ over the course of starvation - CORRECT ANSWER - increase the most
exogenous pathway definition - CORRECT ANSWER - refers to the metabolism of
lipoproteins that contain lipid derived from the diet
endogenous pathway definition - CORRECT ANSWER - refers to the metabolism of
lipoproteins that contain lipid that has been synthesized by tissues or what is being recirculated
after delivery to tissue or storage
exogenous lipoprotein pathway - CORRECT ANSWER - -chylomicrons are secreted from the
intestinal tract
-they acquire Apo CII and Apo E in circulation
-in capillaries near peripheral tissues, they encounter lipoprotein lipase, which is activated by
Apo CII
-LPL breaks down TG's into FFA for peripheral tissues to absorb
-the CM remnant, now depleted of TGs, is taken up by the liver by the binding of ApoE to LDLR
insulin secreted in post-absorptive state - CORRECT ANSWER - -stimulates LPL activity on
capillaries of adipose tissue
-enhances LPL synthesis in adipose tissue and translocation to luminal surface of capillary
endothelium
metabolism of chylomicron remnants - CORRECT ANSWER - -TAG, CE, and fat-soluble
vitamins in CM remnants are removed from the plasma by the liver
Exam Questions and CORRECT Answers
how do lipids move through the lumen of the intestine - CORRECT ANSWER - mixed
micelles
how do lipids move in enterocytes - CORRECT ANSWER - pre and nascent chylomicrons
how do lipids move through lymph - CORRECT ANSWER - modified chylomicron
how do lipids move through blood - CORRECT ANSWER - mature and remnant chylomicron
VLDL, IDL, LDL, HDL
FFA
(TAG)
how do lipids move through adipose tissue - CORRECT ANSWER - TAG
how do lipids move through other tissues - CORRECT ANSWER - cholesterol, PL's, FFA,
TAG
lipoprotein particle size biggest to smallest - CORRECT ANSWER - chylomicron, VLDL,
IDL, LDL, HDL
Chylomicrons - CORRECT ANSWER - arise solely in intestine
contain TAG and cholesteryl ester primarily from diet
,chylomicron remnant - CORRECT ANSWER - chylomicron after most of TAG has been
removed by LPL in capillaries of adipose tissue and muscle
VLDL (very low density lipoprotein) - CORRECT ANSWER - -are secreted solely by the
liver
-contain endogenously synthesized TAG
IDL (intermediate density lipoprotein) - CORRECT ANSWER - -transiently made from
VLDL in capillaries of adipose tissue and muscle
-taken up by liver or converted to LDL
LDL (low-density lipoprotein) - CORRECT ANSWER - -derived from VLDL or IDL
-contains endogenous cholesterol
HDL (High Density Lipoprotein) - CORRECT ANSWER - -important in 'reverse transport' of
cholesterol from extrahepatic tissues to liver
Apo A-1 function - CORRECT ANSWER - -activator of LCAT
-allows binding of HDL to ABCA1 for cholesterol efflux from peripheral tissues
Apo B-100 function - CORRECT ANSWER - -required for secretion of VLDL from liver
-acts as ligand of LDL receptor
Apo B-48 - CORRECT ANSWER - -made from the same gene as Apo B100 but RNA editing
(C-->U) by cytidine deaminase converts E (CAA) to UAA (stop codon)
-required for secretion of chylomicron from intestine
Apo C-II function - CORRECT ANSWER - activator of lipoprotein lipase
, Apo E function - CORRECT ANSWER - acts as ligand of LDL receptor
FFA ______ over the course of starvation - CORRECT ANSWER - increase
TAG ________ over the course of starvation - CORRECT ANSWER - decrease
KB ______ over the course of starvation - CORRECT ANSWER - increase the most
exogenous pathway definition - CORRECT ANSWER - refers to the metabolism of
lipoproteins that contain lipid derived from the diet
endogenous pathway definition - CORRECT ANSWER - refers to the metabolism of
lipoproteins that contain lipid that has been synthesized by tissues or what is being recirculated
after delivery to tissue or storage
exogenous lipoprotein pathway - CORRECT ANSWER - -chylomicrons are secreted from the
intestinal tract
-they acquire Apo CII and Apo E in circulation
-in capillaries near peripheral tissues, they encounter lipoprotein lipase, which is activated by
Apo CII
-LPL breaks down TG's into FFA for peripheral tissues to absorb
-the CM remnant, now depleted of TGs, is taken up by the liver by the binding of ApoE to LDLR
insulin secreted in post-absorptive state - CORRECT ANSWER - -stimulates LPL activity on
capillaries of adipose tissue
-enhances LPL synthesis in adipose tissue and translocation to luminal surface of capillary
endothelium
metabolism of chylomicron remnants - CORRECT ANSWER - -TAG, CE, and fat-soluble
vitamins in CM remnants are removed from the plasma by the liver
