Block 3 Lipid Synth & Storage

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Chachelly
C
Chachelly
Community Contributor
Quizzes Created: 513 | Total Attempts: 630,644
| Attempts: 229
SettingsSettings
Please wait...
  • 1/9 Questions

    A 42-year-old man presents with a chief complaint of intermittent claudication during exercise. His family history is significant for the presence of cardiovascular disease on his father's side, but not on his mother's side. Physical exam reveals xanthelasmas and bilateral tendon xanthomas. A plasma lipid profile reveals a cholesterol level of 340 mg/dL, with a high LDL/HDL ratio. He is given instructions for dietary modifications and a prescription for Zocor (simvastatin). The anticholesterolemic action of simvastatin is based on its effectiveness as a competitive inhibitor of the rate-limiting enzyme in cholesterol biosynthesis. The reaction product normally produced by this enzyme is

    • Squalene
    • Methylmalonate
    • Lanosterol
    • Mevalonate
    • Acetoacetate
Please wait...
Block 3 Lipid Synth & Storage - Quiz
About This Quiz

This quiz titled 'Block 3 Lipid Synth & Storage' assesses knowledge on lipid synthesis and storage mechanisms, focusing on biochemical pathways, genetic disorders like abetalipoproteinemia, and clinical implications related to lipid metabolism. It is crucial for students and professionals in medical and health sciences.


Quiz Preview

  • 2. 

    A patient with a history of recurring attacks of pancreatitis, eruptive xanthomas, and increased plasma triglyceride levels (2000 mg/dL) associated with chylomicrons, most likely has a deficiency in

    • Lipoprotein lipase

    • LDLreceptors

    • HMG-CoA reductase

    • ApoB-48

    • ApoB-lOOreceptor

    Correct Answer
    A. Lipoprotein lipase
    Explanation
    These are the clinical features of lipoprotein lipase deficiency (TypeI lipoproteinemia).
    LDLreceptor defects would result in elevated LDLs.HMG-CoA reductase and
    ApoB-lOOhave no direct relationship to chylomicrons. ApoB-48 deficiencywould result
    in decreased production of chylomicrons.

    Rate this question:

  • 3. 

    Uncontrolled phagocytosis of oxidized LDL particles is a major stimulus for the development of foam cells and fatty streaks in the vascular sub endothelium. This process may be inhibited by increased dietary intake of

    • Vitamin E

    • Vitamin B6

    • Vitamin D

    • Vitamin B12

    • Vitamin K

    Correct Answer
    A. Vitamin E
    Explanation
    Only vitamin E is an antioxidant

    Rate this question:

  • 4. 

    Abetalipoproteinemia is a genetic disorder characterized by malabsorption of dietary lipid, steatorrhea (fatty stools), accumulation of intestinal triglyceride, and hypolipoproteinemia.  A deficiency in the production of which apoprotein would most likely account for this clinical presentation?

    • ApoB-lOO

    • ApoB-48

    • ApoC-II

    • ApoA-I

    • ApoE

    Correct Answer
    A. ApoB-48
    Explanation
    Apo B-48is required for intestinal absorption of dietary fat in the form of chylomicrons.
    Apo B-lOOformation is also impaired in these patients, but this would not
    explain the clinical symptoms described.

    Rate this question:

  • 5. 

    What is the most positive activator of the process shown below? 8 acetylCoA + n ATP + 14NADpH -7 palmitate + 8 CoASH+ nADP + nPi + 14NADP

    • Acetyl CoA

    • Citrate

    • Malonyl CoA

    • Malate

    • Oxaloacetate

    Correct Answer
    A. Citrate
    Explanation
    Citrate is a potent activator of acetylCoA carboxylase for fatty acid synthesis.

    Rate this question:

  • 6. 

    When adipose tissue stores triglyceride arriving from the liver or intestine, glycolysis must also occur in the adipocyte. Which of the following products or intermediates of glycolysis is required for fat storage?

    • Glycerol

    • Glucose 6-phosphate

    • Pyruvate

    • Acetyl CoA

    • Dihydroxyacetone phosphate

    Correct Answer
    A. Dihydroxyacetone phosphate
    Explanation
    To reform triglycerides trom the incoming fatty acids, glycerol 3-P must be
    available.The adipose can produce this only from DHAP in glycolysis.

    Rate this question:

  • 7. 

    Abetalipoproteinemia is a genetic disorder characterized by malabsorption of dietary lipid, steatorrhea (fatty stools), accumulation of intestinal triglyceride, and hypolipoproteinemia   Patients with abetalipoproteinemia exhibit membrane abnormalities in their erythrocytes with production of acanthocytes (thorny-appearing cells). This unusual red cell morphology would most likely result from malabsorption of

    • Palmitic acid

    • Ascorbic acid

    • Arachidonic acid

    • Folic acid

    • Linoleic acid

    Correct Answer
    A. Linoleic acid
    Explanation
    The genetic defect would result in malabsorption of the 3 fatty acids listed, but
    only linoleate is strictly essential in the diet. Absorption of water-soluble ascorbate and
    folate would not be significantly affected.

    Rate this question:

  • 8. 

    A 42-year-old man presents with a chief complaint of intermittent claudication during exercise. His family history is significant for the presence of cardiovascular disease on his father's side, but not on his mother's side. Physical exam reveals xanthelasmas and bilateral tendon xanthomas. A plasma lipid profile reveals a cholesterol level of 340 mg/dL, with a high LDL/HDL ratio. He is given instructions for dietary modifications and a prescription for Zocor (simvastatin). From a Lineweaver-Burk plot, the Km and Vmaxof this rate-limiting enzyme were calculated to be 4 X 10-3 M and 8 X 102 mmol/h, respectively. If the above experiment is repeated in the presence of simvastatin, which of the following values would be obtained?  Km (M)                  V max (mmolJh)

    • 4 X 10(-3) 3 X 10(2) ( ) = to the power of

    • 2 X 10(-3) 1 X 10(2) ( ) = to the power of

    • 4 X 10(-3) 9 X 10(2) ( ) = to the power of

    • 8 X 10(-3 ) 8 X 10(2) ( ) = to the power of

    • 8 X 10(-3) 9 X 10(2) ( ) = to the power of

    Correct Answer
    A. 8 X 10(-3 ) 8 X 10(2) ( ) = to the power of
    Explanation
    With a competitive inhibitor, there will be an increase in Km with no change in
    Vmax'Option A would be for a noncompetitive inhibitor (V max decreased, Km unaltered).

    Rate this question:

  • 9. 

    A 42-year-old man presents with a chief complaint of intermittent claudication during exercise. His family history is significant for the presence of cardiovascular disease on his father's side, but not on his mother's side. Physical exam reveals xanthelasmas and bilateral tendon xanthomas. A plasma lipid profile reveals a cholesterol level of 340 mg/dL, with a high LDL/HDL ratio. He is given instructions for dietary modifications and a prescription for Zocor (simvastatin). The clinical findings noted in this patient are most likely caused by deficient production of

    • Lethicin cholesterol acyltransferase

    • ApoB-lOO receptors

    • Fatty acyl-CoA synthetase

    • VLDL from LDL

    • Cholesterol ester transfer protein

    Correct Answer
    A. ApoB-lOO receptors
    Explanation
    The findings are indicative of heterozygous Type lla familial hypercholesterolemia,
    an autosomal dominant disease. Deficient CETP,LCATor fatty acid CoA synthetase
    would not elevate LDLcholesterol.VLDLare not produced from LDL.

    Rate this question:

Quiz Review Timeline (Updated): Mar 21, 2023 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Mar 21, 2023
    Quiz Edited by
    ProProfs Editorial Team
  • Nov 07, 2011
    Quiz Created by
    Chachelly
Back to Top Back to top
Advertisement
×

Wait!
Here's an interesting quiz for you.

We have other quizzes matching your interest.