Question 1

In phosphatidyl inositol, __________ and _________ usually occupy the C-1 position and the C-2 position, respectively.

Accepted Answer

A)  stearic acid; cholesterol 
B)  stearic acid; arachidonic acid 
C)  palmitolyl acid; arachidonic acid 
D)  oleic acid; arachidonic acid 
E)  None of the answers is correct. 
A)  stearic acid; cholesterol 
B)  stearic acid; arachidonic acid 
C)  palmitolyl acid; arachidonic acid 
D)  oleic acid; arachidonic acid 
E)  None of the answers is correct.

Question 2

Which of the following is a principal component of the lipid-rich covering on neuronal axons?

Accepted Answer

A)  vitamin A 
B)  phosphatidylserine 
C)  sphingomyelin 
D)  triacylglycerol 
E)  None of the answers is correct. 
A)  vitamin A 
B)  phosphatidylserine 
C)  sphingomyelin 
D)  triacylglycerol 
E)  None of the answers is correct.

Question 3

______________________ is the 30-carbon precursor of cholesterol.

Accepted Answer

The answer of ______________________ is the 30-carbon precursor of cholesterol....

Question 4

The energy for the conversion of provitamin D3 to vitamin D3 comes from

Accepted Answer

A)  ATP hydrolysis. 
B)  NADPH oxidation. 
C)  thioester hydrolysis. 
D)  ultraviolet light from the Sun. 
E)  visible light from the Sun. 
A)  ATP hydrolysis. 
B)  NADPH oxidation. 
C)  thioester hydrolysis. 
D)  ultraviolet light from the Sun. 
E)  visible light from the Sun.

Question 5

Which of the following is the immediate product of HMG-CoA reductase in the cholesterol synthesis pathway?

Accepted Answer

A)  isopentenyl pyrophosphate 
B)  mevalonate 
C)  squalene 
D)  farnesyl pyrophosphate 
E)  acetoacetyl CoA 
A)  isopentenyl pyrophosphate 
B)  mevalonate 
C)  squalene 
D)  farnesyl pyrophosphate 
E)  acetoacetyl CoA

Question 6

What is the role of cytochrome P450 monooxygenases in steroid biosynthesis?

Accepted Answer

The formation of cholesterol and its con

Question 7

How do blood levels of lipoproteins serve diagnostic purposes?

Accepted Answer

The ratio of LDL to HDL is important. To

Question 8

What is the major site of triacylglycerol synthesis in mammals?

Accepted Answer

A)  liver 
B)  adipose tissue 
C)  small intestine 
D)  kidney 
E)  pancreas 
A)  liver 
B)  adipose tissue 
C)  small intestine 
D)  kidney 
E)  pancreas

Question 9

In membrane lipid biosynthesis, the nucleotide ________________ is used to activate the components of the reaction.

Accepted Answer

The answer of In membrane lipid biosynthesis, the nucleotide ________________...

Question 10

What is the role of phosphatidyl choline in the synthesis of sphingomyelin?

Accepted Answer

Phosphatidyl choline supplies

Question 11

The major carrier(s) of dietary fat from the intestine is (are)

Accepted Answer

A)  VLDL. 
B)  chylomicrons. 
C)  HDL. 
D)  LDL. 
E)  IDL. 
A)  VLDL. 
B)  chylomicrons. 
C)  HDL. 
D)  LDL. 
E)  IDL.

Question 12

Why are phosphatidylserine, and most other phospholipids, considered classes of molecules, rather than a single molecule?

Accepted Answer

Because various fatty acid gro

Question 13

Vitamin D3 is converted into ______________________, which is an active hormone that functions as a transcription factor.

Accepted Answer

calcitriol

Question 14

What metabolite is reduced to glycerol-3-phosphate for triacylglycerol synthesis?

Accepted Answer

A)  glyceraldehyde-3-phosphate 
B)  3-phosphoglycerate 
C)  phosphoenolpyruvate 
D)  dihydroxyacetone phosphate 
E)  None of the answers is correct. 
A)  glyceraldehyde-3-phosphate 
B)  3-phosphoglycerate 
C)  phosphoenolpyruvate 
D)  dihydroxyacetone phosphate 
E)  None of the answers is correct.

Question 15

Which of the following vitamins is a derivative of cholesterol?

Accepted Answer

A)  vitamin A 
B)  vitamin D 
C)  vitamin E 
D)  vitamin K 
E)  None of the answers is correct. 
A)  vitamin A 
B)  vitamin D 
C)  vitamin E 
D)  vitamin K 
E)  None of the answers is correct.

Question 16

Which lipoprotein transports lipids away from the intestine?

Accepted Answer

A)  chylomicron 
B)  very low density lipoprotein 
C)  low-density lipoprotein 
D)  high density lipoprotein 
E)  None of the answers is correct. 
A)  chylomicron 
B)  very low density lipoprotein 
C)  low-density lipoprotein 
D)  high density lipoprotein 
E)  None of the answers is correct.

Question 17

Tay-Sachs disease is caused by an inability to degrade

Accepted Answer

A)  sphingosine. 
B)  gangliosides. 
C)  dipalmitoyl phosphatidyl choline. 
D)  ceramide. 
E)  None of the answers is correct. 
A)  sphingosine. 
B)  gangliosides. 
C)  dipalmitoyl phosphatidyl choline. 
D)  ceramide. 
E)  None of the answers is correct.

Question 18

Respiratory distress syndrome is caused by a failure in the biosynthetic pathway of

Accepted Answer

A)  sphingosine. 
B)  gangliosides. 
C)  dipalmitoyl phosphatidyl choline. 
D)  cholesterol. 
E)  bile salts. 
A)  sphingosine. 
B)  gangliosides. 
C)  dipalmitoyl phosphatidyl choline. 
D)  cholesterol. 
E)  bile salts.

Question 19

Describe the various ways that 3-hydroxy-3-methylglutaryl CoA reductase is regulated, including both gene expression and enzyme regulation.

Accepted Answer

There are several mechanisms. 1) Synthes

Question 20

A ___________________ is composed of a fatty acid linked to sphingosine via an amide bond.

Accepted Answer

The answer of A ___________________ is composed of a fatty...

Exam 26: Biosynthesis of Membrane Lipids and Steroids

In phosphatidyl inositol, __________ and _________ usually occupy the C-1 position and the C-2 position, respectively.

Which of the following is a principal component of the lipid-rich covering on neuronal axons?

______________________ is the 30-carbon precursor of cholesterol.

The energy for the conversion of provitamin D3 to vitamin D3 comes from

Which of the following is the immediate product of HMG-CoA reductase in the cholesterol synthesis pathway?

What is the role of cytochrome P450 monooxygenases in steroid biosynthesis?

How do blood levels of lipoproteins serve diagnostic purposes?

What is the major site of triacylglycerol synthesis in mammals?

In membrane lipid biosynthesis, the nucleotide ________________ is used to activate the components of the reaction.

What is the role of phosphatidyl choline in the synthesis of sphingomyelin?

The major carrier(s) of dietary fat from the intestine is (are)

Why are phosphatidylserine, and most other phospholipids, considered classes of molecules, rather than a single molecule?

Vitamin D3 is converted into ______________________, which is an active hormone that functions as a transcription factor.

What metabolite is reduced to glycerol-3-phosphate for triacylglycerol synthesis?

Which of the following vitamins is a derivative of cholesterol?

Which lipoprotein transports lipids away from the intestine?

Tay-Sachs disease is caused by an inability to degrade

Respiratory distress syndrome is caused by a failure in the biosynthetic pathway of

Describe the various ways that 3-hydroxy-3-methylglutaryl CoA reductase is regulated, including both gene expression and enzyme regulation.

A ___________________ is composed of a fatty acid linked to sphingosine via an amide bond.

Biochemistry: an Evolving Science

Protein Composition and Structure

Exploring Proteins and Proteomes

DNA, RNA, and the Flow of Genetic Information

Exploring Genes and Genomes

Exploring Evolution and Bioinformatics

Hemoglobin: a Portrait of a Protein in Action

Enzymes: Basic Concepts and Kinetics

Oxidative Phosphorylation

Catalytic Strategies

Regulatory Strategies

Carbohydrates

Lipids and Cell Membranes

Membrane Channels and Pumps

Signal-Transduction Pathways

Metabolism: Basic Concepts and Design

Glycolysis and Gluconeogenesis

The Citric Acid Cycle

The Light Reactions of Photosynthesis

The Calvin Cycle and the Pentose Phosphate Pathway

Glycogen Metabolism

Fatty Acid Metabolism

Protein Turnover and Amino Acid Catabolism

The Biosynthesis of Amino Acids

Nucleotide Biosynthesis

The Integration of Metabolism

DNA Replication, Repair, and Recombination

Rna Synthesis and Processing

Protein Synthesis

The Control of Gene Expression in Prokaryotes

The Control of Gene Expression in Eukaryotes

Sensory Systems

The Immune System

Molecular Motors

Drug Development

Filters

In phosphatidyl inositol, __ and _ usually occupy the C-1 position and the C-2 position, respectively.

The energy for the conversion of provitamin D₃ to vitamin D₃ comes from

Vitamin D₃ is converted into ______________________, which is an active hormone that functions as a transcription factor.