Lipids Part 2

Question 1

_______Lipids

Are bonded to other types of molecules

Answer 1

Complex

Question 2

• Consist of a core of hydrophobic lipids surrounded by amphipathic proteins, phospholipids, and cholesterol

Answer 2

Lipoproteins

Question 3

Composed of both lipids and proteins, called

Answer 3

apolipoproteins

Question 4

T or F

• Larger LPP particles have larger core regions (contain relatively more TAG and cholesteryl ester)

Answer 4

True

Question 5

T or F

The larger the LPP, the more lipid relative to CHON, therefore, lighter in density

Answer 5

True

Question 6

Lipoproteins

Cassification
(based on ultracentrifugation)

Answer 6

• Chylomicrons [chylos]
• Very-low-density LPP [VLDL]
• Low-density LPP [LDL}
• High-density LPP [HDL]

Question 7

80% - 90% triglycerides, 2% protein

Answer 7

Chylomicrons

Question 8

55% - 65% triglycerides,
10% cholesterol,
5% - 10% protein

Answer 8

VLDL

Question 9

10% triglycerides,
50% cholesterol,
25% protein

Answer 9

LDL

Question 10

5% triglycerides,
20% cholesterol,
50% protein

Answer 10

HDL

Question 11

• Location: surface of LPP particles

• Functions:
– Help maintain the structural integrity of LPP
– Serve as ligands for cell receptors
– Act as activators and inhibitors of the various enzymes that modify LPP particles
• Contain “Amphipathic helix”

Answer 11

Apolipoproteins

Question 12

– Major protein on HDL

– Measure of anti-atherogenic HDL present in plasma

Answer 12

Apo A-I

Question 13

– Is a large protein with MW 500 kD

– Principal protein on LDL, VLDL, and Chylomicrons

Answer 13

Apo B

Question 14

Apo B 100 saaa?

Answer 14

LDL
VLDL

Question 15

Apo B 48

Answer 15

Chylomicrons

Question 16

Apo B-100

– Is found on…

– Ligand for the LDL receptor

Answer 16

LDL and VLDL

Question 17

– Exclusively found in chylomicrons

Answer 17

Apo B-48

Question 18

Apo E

– Found in (3)

– Serves as a ligand for the LDL receptor and the chylomicron remnant receptor

– Apo E2, Apo E3, Apo E4

Answer 18

LDL, VLDL, and HDL

Question 19

Major lipoproteins

Answer 19

Chylomicrons
VLDL
LDL
HDL

Question 20

Minor or abnormal lipoproteins

Answer 20

IDL
Lp (a)
Lp (x)
Beta VLDL

Question 21

Chylomicrons

Account for the_____ of postprandial plasma

Readily float to the top of stored plasma and form a_____ layer – chylous, turbid, milky, cloudy, lipemic plasma/serum

Produced by the____

Deliver dietary (exogenous) lipids to…

Answer 21

turbidity

creamy

intestine

hepatic and peripheral cells

Question 22

VERY LOW DENSITY LIPOPROTEIN

Contain

Answer 22

apo B-100, apo E, and apo C

Question 23

VLDL

Produced by the____

Rich in___ like chylomicrons

Account for most of the____ observed in fasting hyperlipidemic plasma specimens but do not form a top, creamy layer

Major carriers of endogenous (hepatic derived) triglycerides

Transfer TAG from the liver to___

Answer 23

liver

TAG

turbidity

peripheral tissue

Question 24

LOW DENSITY LIPOPROTEIN

• Contains apo

Answer 24

B-100 and apo E

Question 25

• Primarily formed as a consequence of the lipolysis of VLDL • Readily taken up by cells via the LDL receptor – Accounts for the reason that elevated LDL levels promote atherosclerosis • Significantly smaller than VLDL and chylomicrons

Answer 25

LDL

Question 26

Smallest and the most dense Synthesized by both the _____ Can exist either as disk-shaped or as spherical-shaped particles

Answer 26

HIGH DENSITY LIPOPROTEIN liver and intestine

Question 27

– Most active form in removing excess cholesterol from peripheral cells

Answer 27

DISCOIDAL HDL

Question 28

– HDL2 • Larger in size and richer in lipid than HDL3 • May be more efficient in delivering lipids to the liver – HDL3

Answer 28

SPHERICAL HDL

Question 29

• Intermediate Density Lipoprotein • Lipoprotein (a) • LpX Lipoprotein • ẞ-VLDL Lipoprotein or Floating ẞ Lipoprotein

Answer 29

Minor: Abnormal:

Question 30

• Formed through the metabolism of VLDL in circulation; lipid content, size, and density of IDL is intermediate between VLDL and LDL

Answer 30

Intermediate Density Lipoprotein

Question 31

• is similar to LDL in terms of density and overall composition, and can be thought of as an LDL particle to which apo(a) has been added, linked to apoB-100 via a disulfide bond

Answer 31

Lipoprotein (a)

Question 32

• is an abnormal lipoprotein found in patients with biliary cirrhosis or cholestasis, and in patients with familial lecithin/cholesterol acyltransferase (LCAT) deficiency

Answer 32

LpX Lipoprotein

Question 33

• is an abnormal lipoprotein that accumulates in type 3 hyperlipoproteinemia

Answer 33

ẞ-VLDL Lipoprotein / Floating ẞ Lipoprotein

Question 34

T or F Serum lipoprotein concentrations differ between adult men and women

Answer 34

True

Question 35

T or F Men and women both show a tendency toward increased total cholesterol, LDL cholesterol, and triglyceride concentrations with age

Answer 35

True

Question 36

T or F Circulating levels of total cholesterol, LDL cholesterol, and triglycerides in young children are generally much lower than those seen in adults

Answer 36

True

Question 37

Diseases associated with abnormal lipid concentrations

Answer 37

DYSLIPIDEMIA

Question 38

2 CATEGORIES: Dyslipidemia

Answer 38

– Hyperlipoproteinemias – Hypolipoproteinemias

Question 39

HYPERLIPOPROTEINEMIA 3 SUBDIVISIONS:

Answer 39

hypercholesterolemia hypertriglyceridemia combined hyperlipidemia

Question 40

• Most closely linked to heart disease • Increased in LDL cholesterol • Genetic abnormalities

Answer 40

Hypercholesterolemia

Question 41

Individuals synthesize intracellular cholesterol normally, but lack, or are deficient in, active LDL receptors

Answer 41

FAMILIAL HYPERCHOLESTEROLEMIA

Question 42

• Result of an imbalance between synthesis and clearance of VLDL in the circulation • Life-threatening abnormality because it can cause acute and recurrent pancreatitis

Answer 42

Hypertriglyceridemia

Question 43

• Presence of elevated levels of serum total cholesterol and triglycerides • Considered at increased risk of CHD

Answer 43

Combined Hyperlipoproteinemia

Question 44

– TYPE III HYPERLIPOPROTEINEMIA (Fredrickson Classification

Answer 44

FAMILIAL DYSBETALIPOPROTEINEMIA

Question 45

– Currently thought to confer increased risk of CHD and CVD – Can block plasminogen, forming clots along the arterial wall that will not be dissolved

Answer 45

Lp(a) Elevation

Question 46

• Are abnormalities marked by decreased lipoprotein concentrations

Answer 46

HYPOLIPOPROTEINEMIA

Question 47

Hypolipoproteinemia (2)

Answer 47

– Hypoalphalipoproteinemia – Hypobetalipoproteinemia

Question 48

– Indicates an isolated decrease in circulating HDL –______ Disease

Answer 48

Hypoalphalipoproteinemia Tangier

Question 49

Hpoalphaproteinemia • HDL concentrations as low as • Total chole as low as

Answer 49

1-2 mg/dL (0.03 – 0.05 mmol/L) 50 – 80 mg/dL (1.3 – 2.1 mmol/L)

Question 50

mutations in the ABCA1 gene or the ABCA1 transporter, which mediates the first step of the reverse choesterol transport pathway

Answer 50

Hypoalphalipoproteinemia

Question 51

• is a disorder consisting of low levels of LDL cholesterol or apolipoprotein B

Answer 51

Hypobetalipoproteinemia

Question 52

LCAT deficiency (2)

Answer 52

Complete (homozygous Mild (heterozygous)

Question 53

• Corneal clouding • Nephropathy • Hemolytic anemia • HDL deficiency • Fish-eye

Answer 53

– Complete (homozygous) – Mild (heterozygous)