BOC Chemistry Study Guide: Focus on Lipids & Lipoproteins (Pages 194-210)

194. (MLS ONLY) High levels of which lipoprotein class are associated with decreased risk of

accelerated atherosclerosis?

a chylomicrons

b VLDL

c LDL

d HDL

d HDL

(MLS ONLY) The most consistent analytical error involved in the routine determination of HDL-cholesterol is caused by:

a incomplete precipitation of LDL-cholesterol

b coprecipitation of HDL- and LDL-cholesterol

c inaccurate protein estimation of HDL-cholesterol

d a small concentration of apoB-containing lipoproteins after precipitation

d a small concentration of apoB-containing lipoproteins after precipitation

(MLS ONLY) If the LDL-cholesterol is to be calculated by the Friedewald formula, what are the 2 measurements that need to be carried out by the same chemical procedure?

a total cholesterol and HDL-cholesterol

b total cholesterol and triglyceride

c triglyceride and chylomicrons

d apolipoprotein A and apolipoprotein B

a total cholesterol and HDL-cholesterol

(MLS ONLY) The chemical composition of HDL-cholesterol corresponds to:

Triglyceride Cholesterol Protein

a 60% 15% 10%

b 10% 45% 25%

c 5% 15% 50%

d 85% 5% 2%

c 5% 15% 50%

(MLS ONLY) In familial hypercholesterolemia, the hallmark finding is an elevation of:

a low-density lipoproteins

b chylomicrons

c high-density lipoproteins

d apolipoprotein A1

a low-density lipoproteins

(MLS ONLY) Premature atherosclerosis can occur when which of the following becomes elevated?

a chylomicrons

b prostaglandins

c low-density lipoproteins

d high-density lipoproteins

a chylomicrons

(MLS ONLY) Transportation of 60%-75% of the plasma cholesterol is performed by:

a chylomicrons

b very low-density lipoproteins

c low-density lipoproteins

d high-density lipoproteins

c low-density lipoproteins

(MLS ONLY) Which of the following diseases results from a familial absence of high density lipoprotein?

a Krabbe disease

b Gaucher disease

c Tangier disease

d Tay-Sachs disease

c Tangier disease

A 1-year-old girl with a hyperlipoproteinemia and lipase deficiency has the following lipid profile

cholesterol: 300 mg/dL (7.77 mmol/L)

LDL: increased

HDL: decreased

triglycerides: 200 mg/dL (2.26 mmol/L)

chylomicrons: present

A serum specimen for this patient that was refrigerated overnight would most likely be:

a clear

b cloudy

c creamy layer over cloudy serum

d creamy layer over clear serum

d creamy layer over clear serum

(MLS ONLY) Which of the following lipid results would be expected to be falsely elevated on a serum specimen, from a nonfasting patient?

a cholesterol

b triglyceride

c HDL

d LDL

b triglyceride

(MLS ONLY) A 9-month-old boy from Israel has gradually lost the ability to sit up, and develops seizures. He has an increased amount of a phospholipid called GM2-ganglioside in his neurons, and he lacks the enzyme hexosaminidase A in his leukocytes. These findings suggest:

a Neimann-Pick disease

b Tay-Sachs disease

c phenylketonuria

d Hurler syndrome

b Tay-Sachs disease

(MLS ONLY) In amniotic fluid, the procedure used to determine fetal lung maturity is:

a lecithin/sphingomyelin ratio

b creatinine

c measurement of absorbance at 450nm

d alpha-fetoprotein

a lecithin/sphingomyelin ratio

(MLS ONLY) Refer to the following illustration:

(IMAGE)

The class of phospholipid surfactants represented by the dotted line on the amniotic fluid anaiy shown above is thought to originate in what fetal organ system?

a cardiovascular

b pulmonary

c hepatic

d placental

b pulmonary

(MLS ONLY) A fasting serum sample from an asymptomatic 43-year-old woman is examined visually and chemically with the following results:

initial appearance of serum: milky

appearance of serum after overnight refrigeration: cream layer over turbid serum triglyceride level: 2,000 mg/dL (22.6 mmol L)

cholesterol level: 550 mg/dL (14.25 mmol L)

This sample contains predominantly:

a chylomicrons, alone

b chylomicrons and very low-density lipoproteins (VLDL)

c very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL)

d high-density lipoproteins (HDL)

b chylomicrons and very low-density lipoproteins (VLDL)

Chylomicrons are present in which of the following dyslipidemias?

a familial hypercholesterolemia

b hypertriglyceridemia

c deficiency in lipoprotein lipase activity

d familial hypoalphalipoproteinemia

c deficiency in lipoprotein lipase activity

(MLS ONLY) The function of the major lipid components of the very low-density lipoproteins (VLDL) is to transport:

a cholesterol from peripheral cells to the liver

b cholesterol and phospholipids to peripheral cells

c exogenous triglycerides

d endogenous triglycerides

d endogenous triglycerides

210. Turbidity in serum suggests elevation of:

a cholesterol

b total protein

c chylomicrons

d albumin

c chylomicrons