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Flashcards in Lipids Deck (45):
1

Fatty acids:which is false?
A.only a relatively small amount exists in the free or unesterified form in plasma
B.most are non-covalently bound to albumin
C. are found as a constituent of triglycerides or phospholipids
D.are covalently attached to the glycerol backbone of triglycerides and phospholipids by a peptide bond

D

Ester dapat

2

most common phospholipid found on lipoproteins & cell membranes

phosphatidylcholine

3

Which is false?
A. phospholipids are only synthesised in the liver
B. Cholesterol esters are neutral lipids
C. phospholipids are amphipathic
D. size is directly proportional to apolipoprotein's relative lipid content

A

all cytosolic cell compartments :)

4

False about dietary phytosterols' effect
A. ↓ plasma total cholesterol
B. ↓ LDL cholesterol
C. ↓ HDL cholesterol

C

5

The liver does not convert cholesterol into:
A.cholic acid
B.glucocorticoids
C.vitamin B
D. NOTA

C
vitamin D3 dapat

6

enumerate 2 basis of classification for lipoproteins

Electrophoretic mobility
Buoyant density

7

Which is false?
A.Chylomicron – most (-) charge
B. β-lipoprotein – for VLDL
C.Pre β-lipoprotein – for LDL
D.α-lipoprotein – for chylomicron

D - for HDL dapat

8

Which is false about chylomicrons?
A.Largest and the least dense of the lipoproteins
B.scatter light, hence turbid/milky appearance of postprandial plasma
C.produced by the intestine where they are packaged with dietary lipids and apo B-100
D.in-charge of delivery of dietary lipids to hepatic and peripheral cells

C. apo B-48 dapat

9

False about VLDL
A.Produced by the liver
B.Contains apo B-100 – main apolipoprotein
C.form a creamy top layer like chylomicrons
D.major carriers of endogenous (from
synthesis of the body) triglycerides

C. They do not form a creamy top layer

10

high levels of intermediate-density lipoproteins are found in patients with familial hyperlipoproteinemia. why?x

Due to an abnormal form of apo E that delays the clearance of IDL; Individuals affected have significant risk for peripheral vascular disease (PVD) and coronary artery disease (CAD)

11

False about LDL
A. Large LDL particles have beenshown to be more proatherogenic and may be a better marker for CHD risk
B. Readily taken up by cells via the LDL receptor in the liverand peripheral cells
C. LDL particles have been separated through density ultracentrifugation or gradient gel electrophoresis
D. smaller particles are denser and have relatively more
triglyceride than cholesteryl esters

A
Smaller dapat

12

macrophages that take up too much lipid - what happens to them?

Filled with intracellular lipid drops o Turned into foam cells
 predominant cell type of fatty streaks
 early precursor of atherosclerotic plaques

13

false about lipoprotein (A)
A. Are LDL-like particles that contain one molecule of apo(a) linked to apo B-100 by a single ester bond
B. Lp(a) is larger than LDL and has a higher lipid content
and a slightly lower density
C. postulated to be removed @ kidneys
D. Have a high level of homology with plasminogen, a precursor of plasmin that promotes clot lysis via fibrin
cleavage

A
sulfide dapat

14

false about HDL
A.Transport cholesterol to liver for metabolism
B.The smallest and most dense lipoprotein particle
C.Is synthesized by liver only

C
liver and intestine dapat

15

most active form of HDL in removing excess cholesterol from peripheral cells
A. Discoidal
B. Spherical
C. equal lang

A

16

abnormal lipoprotein present in patients with biliary cirrhosis or cholestasis and in patients with mutations in lecithin:cholesterolacyltransferase (LCAT), the enzyme that esterifies cholesterol

lipoprotein X

17

False about lipoprotein X
A.Is different from other lipoproteins in the endogenous pathway due to the lack of apoB-48
B.Phospholipids and non-esterified cholesterol are the lipid components
C.albumin and apoC are the main protein components D.mainly removed by the reticuloendothelial system of the liver and the spleen

A
apo B-100 dapat

18

false abt apolipoproteins
A.Are primarily located on the bottom of lipoprotein particles
B.Help maintain the structural integrity of lipoproteins
C.Also serve as ligands for cell receptors and as activators and inhibitors of the various enzymes that modify
lipoprotein particles

A
surface dapat

19

apolipoproteins contain a structural motif called an ___which accounts for the ability of these proteins to bind to lipids

amphipathic helix

20

identify
-- The major protein of HDL
-- Frequently used as a measure of the amount of the
antiatherogenic HDL present in plasma

apo A-1

21

differentiate apo B-100 fr Apo B-48

Apo B-100: LDL, VLDL
Apo B-48: chylomicrons

22

fill in the blanks
1. Patients who are homozygous for the __
isoform are at an increased risk for developing type
III hyperlipoproteinemia.
2. individuals with the __ isoform have been
shown to have an increased risk of developing
Alzheimer’s disease

1. apo E2
2. apo E4

23

These 3 processes depend on apo B–containing lipoprotein particles. These three pathways are critical in the transport to peripheral cells of fatty acids generated during the lipolysis of triglycerides and cholesteryl esters
Their net result is also the net delivery of cholesterol to peripheral cells,

identify the 3 processes

LIPID ABSORPTION PATHWAY, EXOGENOUS PATHWAY, AND ENDOGENOUS PATHWAY

24

false about reverse cholesterol transport pathway
A.principal way that peripheral cells maintain their cholesterol equilibrium
B.is mediated by chylomicrons
C. Excess cholesterol from peripheral cells is transported
back to the liver
D.excess cholesterol may be excreted into the bile as free cholesterol or after being converted to bile acids

B

HDL dapat

25

Which is true?
A.Men have higher HDL-C levels and lower total cholesterol and triglyceride levels than women
B.The difference in total cholesterol, however,
disappears after menopause as oestrogen decreases
C.Men and women both show a tendency toward increased total cholesterol, LDL-C, and triglyceride
concentrations with age.
D.The incidence of heart disease is strongly associated with serum cholesterol concentration, particularly LDL-C.

A
Baliktad.

26

False about arteriosclerosis
A.The relationship between heart disease and dyslipidemias stems from the deposition of lipids in artery walls.
B.Lipid deposits are frequently associated with increases serum concentrations of LDL-C or decreased HDL-C
C.For patients with established heart disease, aggressive treatment to reduce HDL-C levels below 100mg/L (2.6mmol/L) or even lower is effective in stabilization, and sometimes regression of plaques.

C
LDL DAPAT

27

false about FAMILIAL HYPERCHOLESTEROLEMIA (FH)
A.Homozygotes for FH are common
B.Heterozygotes for FH are rare
C. BOTA
D. NOTA

C
baliktad e :3

28

identify the FAMILIAL HYPERCHOLESTEROLEMIA (FH) symptoms
A.___ :cholesterol deposits under the skin
B. __ :cholesterol deposits in the cornea

tendinous/tuberous xanthomas
arcus

29

False about Lp(A) elevation
A. Higher Lp(a) levels have been observed in patients with CHD
B. Has a high degree of homology with plasminogen increasing plaque formation
C. Most LDL-lowering drugs have significant effect on Lp(a) concentration

C
insignificant dapat

30

identify type of cholesterol
reflects total cholesterol minus HDL-C and encompasses all cholesterol present in potentially atherogenic, apo B–containing lipoproteins [LDL, VLDL, IDL, and Lp(a)]

non-HDL Cholesterol

31

Which is false about non-HDL C?
A. Non–HDL-C is not reliable when measured in the non-fasting state
B. Studies have shown that elevated levels of non–HDL-C are associated with increased CVD risk even if the LDL- C levels are normal
C. Non–HDL-C has been found to be an independent predictor of CVD and for diabetes patients

A
reliable siya

32

T/F
hypobetalipoproteinemia is associated with isolated low levels of LDL-C

T

33

identify the disease
 extreme hypoalphalipoproteinemia
 HDL-C concentrations as low as 1 to 2 mg/dL (0.03 to
0.05 mmol/L) in homozygotes
 total cholesterol concentrations of 50 to 80 mg/dL (1.3 to
2.1 mmol/L)

Tangier Disease

34

false about cholesterol measurement
A. At least 6hr fasting: preferred for total cholesterol testing, required for triglyceride testing
B. The lipoproteins, HDL and LDL are quantified based on their cholesterol content

A
12hr dapat

35

identify past method of cholesterol det

Hexane extraction after hydrolysis with alcoholic KOH Reaction with Liebermann- Burchard color reagent (sulfuric and acetic acids and acetic anhydride)

36

identify present method of cholesterol det

Gas chromatography–mass spectrometry (GC–MS):

37

Triglyceride value: used in the estimation of LDL-C by
what means of computation

Friedewald equation

38

Enum methods for sep & quanti of serum lipoproteins

1.Ultracentrifugation
2. Electrophoretic separations
3. Chemical precipitation methods
4.Immunochemical methods
5. Chromatographic methods

39

identify the lipid measurement tool most common in clinical laboratories; designed for fully automated use with chemistry analyzers, using combinations of detergents and, antibodies to selectively assay cholesterol in lipoprotein classes

Direct homogeneous reagents -

40

Enum methods to measure HDL

Three-step method (reference method by CDC):
Direct precipitation method (simpler)

41

Identify HDL meas method
 ultracentrifugation to remove VLDL
 heparin manganese precipitation from the 1.006
g/mL infranate to remove LDL
 analysis of supernatant cholesterol by the Abell-
Kendall assay

three step method

42

identify HDL meas method
direct dextran sulfate (50 kD) precipitation of serum
with Abell-Kendall cholesterol analysis

direct precipitation method

43

Point-of-care testing at the patient’s bedside, in the physician’s office, in wellness centers, and even in the
home

identify lipid meas tool

compact analyzer

44

Choline-containing phospholipids lecithin,
lysolecithin, and sphingomyelin are measured by an enzymatic reaction sequence using 3 enzymes. enum!

phospholipase D, choline oxidase, and horseradish peroxidase

45

fatty acid meas commonly analysed via ___

gas–liquid chromatography