FINALS - LIPIDS AND LIPOPROTEIN

Question 1

What is the main function of chylomicrons?

Answer 1

Transport dietary triglycerides to peripheral tissues

Question 2

Which lipoprotein is responsible for redistributing dietary and hepatic-synthesized triglycerides during fasting?

Answer 2

VLDL

Question 3

Which lipoprotein gathers up excess cholesterol for transport back to the liver?

Answer 3

LDL

Question 4

What disease is associated with abnormal serum lipids (dyslipidemia)?

Answer 4

Coronary Heart Disease (CHD)

Question 5

What is the consequence of having elevated levels of Intermediate-Density Lipoproteins (IDLs)?

Answer 5

Higher risk of peripheral vascular disease (PVD) and coronary artery disease (CAD)

Question 6

Which type of fatty acids do most triglycerides from plant sources contain?

Answer 6

Polyunsaturated fatty acids

Question 7

What type of fatty acid configuration typically forms oils at room temperature?

Answer 7

Cis unsaturated fatty acids

Question 8

In what form do fatty acids mostly exist in plasma?

Answer 8

Constituent of triglycerides or phospholipids

Question 9

Which type of lipoprotein is rich in triglycerides and is the major carrier of endogenous triglycerides?

Answer 9

VLDL

Question 10

What is a characteristic feature of LDL particles?

Answer 10

Contain Apo B100 and are cholesterol-rich

Question 11

Which lipoprotein particles are described as being very hydrophobic and virtually water insoluble?

Answer 11

Triglycerides

Question 12

What type of bond links Apo(a) to Apo B100 in Lp(a) particles?

Answer 12

Disulfide bond

Question 12

What type of bond attaches fatty acids to the glycerol backbone in triglycerides?

Answer 12

Ester bond

Question 13

Which lipoprotein is associated with an increased CHD risk when its particles are small and dense?

Answer 13

LDL

Question 14

What is the role of cholesterol in the body?

Answer 14

Facilitate triglyceride transport by lipoproteins

Maintain normal structure and integrity of cell
membranes

Act as a precursor for steroid hormone synthesis

Question 15

What determines the size and density heterogeneity of Lp(a) particles?

Answer 15

The number of repeating peptide sequences called kringles

Question 16

What condition is associated with elevated levels of Lp(a) (>30 mg/dL)?

Answer 16

Premature CHD and stroke

Question 17

What primarily affects the plasma levels of Lp(a) within an individual?

Answer 17

Isoform size

Question 17

What is the primary mechanism proposed to explain the antiatherogenic property of HDL?

Answer 17

Reverse cholesterol transport

Question 18

Which organ is postulated to be responsible for the removal of Lp(a)?

Answer 18

Kidney

Question 19

Which type of HDL is larger and less dense?

Answer 19

HDL2

Question 20

What percentage of dietary triglycerides are typically absorbed by the intestine?

Answer 20

Greater than 90%

Question 20

Which pathway involves the transport of fatty acids generated during lipolysis to peripheral cells?

Answer 20

Exogenous pathway

Question 20

What forms large aggregates with bile acids during lipid absorption?

Answer 20

Micelles

Question 21

Where are newly synthesized chylomicrons initially secreted?

Answer 21

Into the lacteals

Question 22

Dyslipidemia as a risk factor for CVD is well-documented to begin in which age group?

Answer 22

Childhood

Question 23

What happens to VLDL particles after lipolysis in the endogenous pathway?

Answer 23

They become IDLs or VLDL remnants

Question 24

What is the primary underlying cause of arteriosclerosis?

Answer 24

Buildup of cholesterol plaques

Question 25

Which type of arteriosclerosis involves the hardening and narrowing of large arteries?

Answer 25

Atherosclerosis

Question 26

What can fatty streaks develop into over time?

Answer 26

Plaques

Question 27

What is the term for cholesterol deposits in the skin that form nodules?

Answer 27

Xanthomas

Question 28

Which condition is associated with cholesterol deposits in tendons?

Answer 28

Familial hypercholesterolemia

Question 29

Hypertriglyceridemia with a triglyceride level greater than 500 mg/dL is considered:

Answer 29

Very high

Question 30

Which hormone is known to influence serum triglyceride levels by triggering hormone-sensitive lipase?

Answer 30

Epinephrine

Question 31

Combined hyperlipidemia involves the elevation of which serum levels?

Answer 31

Both cholesterol and triglycerides

Question 32

Elevations in Lp(a) levels in conjunction with LDL are associated with increased risk for which conditions?

Answer 32

CHD and CVD

Question 33

Hypobetalipoproteinemia is characterized by low levels of which lipoprotein?

Answer 33

LDL

Question 34

What characterizes hypoalphalipoproteinemia?

Answer 34

Isolated decrease in HDL

Question 35

Which of the following conditions is associated with fatty acid synthesis due to increased shunting of glucose into the pentose pathway?

Answer 35

Diabetes mellitus

Question 36

Why are lipids and lipoproteins measured in clinical practice?

Answer 36

To estimate the risk of coronary heart disease (CHD)

Question 37

Which type of sample is typically preferred for total cholesterol testing?

Answer 37

Serum or plasma specimens from fasting patients

Question 38

What can be done to a serum/plasma specimen to preserve it if analysis is delayed?

Answer 38

Refrigerate at 4°C

Question 39

Why are triglyceride measurements usually done on a fasting sample?

Answer 39

Because triglycerides can significantly increase after a meal

Question 40

What physical properties are used in the separation and quantitation of serum lipoproteins?

Answer 40

Density, size, charge, and apolipoprotein content

Question 41

Which method combines ultracentrifugation and chemical precipitation for LDL-C quantitation?

Answer 41

β-quantification

Question 42

What is Apo A1 commonly used to measure in clinical diagnostics?

Answer 42

HDL levels as cholesterol content

Question 42

Which apolipoprotein is considered a better indicator of atherogenic particles than LDL-C?

Answer 42

Apo B

Question 43

Which choline-containing phospholipids account for at least 95% of total phospholipids in serum?

Answer 43

Lecithin, lysolecithin, and sphingomyelin

Question 44

Which variant of LDL has been shown as an independent indicator of CHD risk?

Answer 44

Lp(a)

Question 45

Why is ultracentrifugation preferred for VLDL separation in LDL-C quantitation?

Answer 45

Other methods may have interference from chylomicrons