Question 1

Which group of small molecules best fit the boxes associated with the reaction shown?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
A)  I 
B)  II 
C)  III 
D)  IV C

Question 2

When is propionyl-CoA carboxylase required for the complete oxidation of a fatty acid?

Accepted Answer

A)  When it has an even number of carbons. 
B)  When it has an odd number of carbons. 
C)  When it is a monounsaturated fatty acid. 
D)  When it is a polyunsaturated fatty acid. 
E)  Never 
A)  When it has an even number of carbons. 
B)  When it has an odd number of carbons. 
C)  When it is a monounsaturated fatty acid. 
D)  When it is a polyunsaturated fatty acid. 
E)  Never B

Question 3

ACP used in fatty acid synthesis is an abbreviation for:

Accepted Answer

A)  Acetyl-CoA phosphate. 
B)  Adenosine cyclo-phosphate. 
C)  Acyl Carnitine Protein 
D)  Acyl Carrier Protein. 
E)  None of these is correct. 
A)  Acetyl-CoA phosphate. 
B)  Adenosine cyclo-phosphate. 
C)  Acyl Carnitine Protein 
D)  Acyl Carrier Protein. 
E)  None of these is correct. D

Question 4

The carrier molecule which transports fatty acids through the inner mitochondrial membrane is

Accepted Answer

A)  ATP. 
B)  Carnitine. 
C)  Coenzyme A. 
D)  Lipoic Acid. 
E)  none of these 
A)  ATP. 
B)  Carnitine. 
C)  Coenzyme A. 
D)  Lipoic Acid. 
E)  none of these

Question 5

How is acetyl-CoA transported from the mitochondria to the cytosol for fatty acid synthesis?

Accepted Answer

A)  directly as acetyl-CoA 
B)  through a temporary linkage to carnitine 
C)  as citric acid 
D)  There is no reason to transport acetyl-CoA from the mitochondria to the cytosol, since it is produced primarily in the cytosol. 
A)  directly as acetyl-CoA 
B)  through a temporary linkage to carnitine 
C)  as citric acid 
D)  There is no reason to transport acetyl-CoA from the mitochondria to the cytosol, since it is produced primarily in the cytosol.

Question 6

Isoprenoid derivatives play what role in steroid biosynthesis?

Accepted Answer

A)  inhibit a key step 
B)  are key intermediates 
C)  compete with steroid biosynthesis for a limited precursor 
D)  its role is unknown 
A)  inhibit a key step 
B)  are key intermediates 
C)  compete with steroid biosynthesis for a limited precursor 
D)  its role is unknown

Question 7

Which of the following is true about the FTO gene and obesity?

Accepted Answer

A)  People with the FTO gene will be obese 
B)  Scientists know exactly how the FTO gene leads to obesity 
C)  Individuals with a specific variant of the FTO gene are a little over 1.5 times as likely to be obese 
D)  All of these are true 
A)  People with the FTO gene will be obese 
B)  Scientists know exactly how the FTO gene leads to obesity 
C)  Individuals with a specific variant of the FTO gene are a little over 1.5 times as likely to be obese 
D)  All of these are true

Question 8

Which of the following is not true regarding catabolism of triacylglycerols?

Accepted Answer

A)  Control of release of fatty acids from triacylglycerols in adipocytes involves cyclic AMP as a second messenger. 
B)  When cAMP is a second messenger in the catabolsim of triacylglycerols, it activates a protein kinase 
C)  The protein kinase, once activated, cleaves fatty acids from the triacylglycerol 
D)  The phosphorylated form of triacylglycerol lipase is the active form 
E)  All of these are true 
A)  Control of release of fatty acids from triacylglycerols in adipocytes involves cyclic AMP as a second messenger. 
B)  When cAMP is a second messenger in the catabolsim of triacylglycerols, it activates a protein kinase 
C)  The protein kinase, once activated, cleaves fatty acids from the triacylglycerol 
D)  The phosphorylated form of triacylglycerol lipase is the active form 
E)  All of these are true

Question 9

The addition of two-carbon units to a growing fatty acid chain is directly driven by

Accepted Answer

A)  reduction of NADP+ 
B)  oxidation of NADPH 
C)  decarboxylation of malonyl-CoA 
D)  hydrolysis of ATP 
A)  reduction of NADP+ 
B)  oxidation of NADPH 
C)  decarboxylation of malonyl-CoA 
D)  hydrolysis of ATP

Question 10

Carnitine acyltransferase is located in the mitochondrial

Accepted Answer

A)  intermembrane space. 
B)  outer membrane. 
C)  inner membrane. 
D)  matrix. 
A)  intermembrane space. 
B)  outer membrane. 
C)  inner membrane. 
D)  matrix.

Question 11

Which of the following mechanisms explains why fatty acid synthesis and breakdown do not compete with each other in the body?

Accepted Answer

A)  Synthesis and breakdown take place in two separate compartments of the cell. 
B)  One process uses NADH/NAD+ and the other uses NADPH/NADP+. 
C)  They are not attached to the same carrier molecule in the two processes. 
D)  All of these mechanisms are in operation. 
E)  None of these 
A)  Synthesis and breakdown take place in two separate compartments of the cell. 
B)  One process uses NADH/NAD+ and the other uses NADPH/NADP+. 
C)  They are not attached to the same carrier molecule in the two processes. 
D)  All of these mechanisms are in operation. 
E)  None of these

Question 12

Which of the following best describes carnitine?

Accepted Answer

A)  It transports fatty acids across the inner mitochondrial membrane for breakdown. 
B)  It transports acetyl-CoA to the cytosol for fatty acid synthesis. 
C)  It's a precursor of cholesterol. 
D)  It carries growing acyl chains during fatty acid synthesis. 
E)  none of these 
A)  It transports fatty acids across the inner mitochondrial membrane for breakdown. 
B)  It transports acetyl-CoA to the cytosol for fatty acid synthesis. 
C)  It's a precursor of cholesterol. 
D)  It carries growing acyl chains during fatty acid synthesis. 
E)  none of these

Question 13

Leptin is

Accepted Answer

A)  a peptide hormone 
B)  an appetite supressant 
C)  a hormone that stimulates fat breakdown 
D)  all of these 
A)  a peptide hormone 
B)  an appetite supressant 
C)  a hormone that stimulates fat breakdown 
D)  all of these

Question 14

The acyl carrier used in fatty acid synthesis is similar to coenzyme A.

Accepted Answer

A) True 
 B)False

Question 15

"Ketone bodies" are formed when

Accepted Answer

A)  oxaloacetate is converted to acetoacetyl-CoA. 
B)  there is a deficiency of acetyl-CoA. 
C)  there is not enough oxaloacetate to react with available acetyl-CoA. 
D)  an organism consumes excessive amounts of carbohydrate compared to its lipid intake. 
E)  none of these 
A)  oxaloacetate is converted to acetoacetyl-CoA. 
B)  there is a deficiency of acetyl-CoA. 
C)  there is not enough oxaloacetate to react with available acetyl-CoA. 
D)  an organism consumes excessive amounts of carbohydrate compared to its lipid intake. 
E)  none of these

Question 16

The enzyme activity catalyzing the reaction shown is best termed a

Accepted Answer

A)  reductase 
B)  ketothiolase 
C)  transferase 
D)  dehydratase 
A)  reductase 
B)  ketothiolase 
C)  transferase 
D)  dehydratase

Question 17

How many ATPs can be netted from the complete oxidation of palmitate (C16) to CO2 & H2O?

Accepted Answer

A)  ATPs ≤ 40 
B)  40 < ATPs ≤ 80 
C)  80 < ATPs ≤ 120 
D)  1200 < ATPs 
A)  ATPs ≤ 40 
B)  40 < ATPs ≤ 80 
C)  80 < ATPs ≤ 120 
D)  1200 < ATPs

Question 18

Which of the following is true about neuropeptide Y?

Accepted Answer

A)  it leads to increased appetite 
B)  it is a melanocortin 
C)  it leads to supressed appetite 
D)  It is a steroid hormone 
E)  none of these 
A)  it leads to increased appetite 
B)  it is a melanocortin 
C)  it leads to supressed appetite 
D)  It is a steroid hormone 
E)  none of these

Question 19

Isomerization of the double bonds of polyunsaturated fatty acids involves both cis-trans isomerization and changing the position of the double bonds.

Accepted Answer

A) True 
 B)False

Question 20

The ultimate precursor of all the carbon atoms in steroids is

Accepted Answer

A)  acetyl-CoA (acetyl group) 
B)  oxaloacetate 
C)  succinyl-CoA (succinyl group) 
D)  α-ketoglutarate 
A)  acetyl-CoA (acetyl group) 
B)  oxaloacetate 
C)  succinyl-CoA (succinyl group) 
D)  α-ketoglutarate

Exam 21: Lipid Metabolism

Which group of small molecules best fit the boxes associated with the reaction shown?

When is propionyl-CoA carboxylase required for the complete oxidation of a fatty acid?

ACP used in fatty acid synthesis is an abbreviation for:

The carrier molecule which transports fatty acids through the inner mitochondrial membrane is

How is acetyl-CoA transported from the mitochondria to the cytosol for fatty acid synthesis?

Isoprenoid derivatives play what role in steroid biosynthesis?

Which of the following is true about the FTO gene and obesity?

Which of the following is not true regarding catabolism of triacylglycerols?

The addition of two-carbon units to a growing fatty acid chain is directly driven by

Carnitine acyltransferase is located in the mitochondrial

Which of the following mechanisms explains why fatty acid synthesis and breakdown do not compete with each other in the body?

Which of the following best describes carnitine?

Leptin is

The acyl carrier used in fatty acid synthesis is similar to coenzyme A.

"Ketone bodies" are formed when

The enzyme activity catalyzing the reaction shown is best termed a

How many ATPs can be netted from the complete oxidation of palmitate (C16) to CO2 & H2O?

Which of the following is true about neuropeptide Y?

Isomerization of the double bonds of polyunsaturated fatty acids involves both cis-trans isomerization and changing the position of the double bonds.

The ultimate precursor of all the carbon atoms in steroids is

Biochemistry and the Organization of Cells

Water: the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three-Dimensional Structure of Proteins

Protein Purification and Characterization Techniques

The Behavior of Proteins: Enzymes

The Behavior of Proteins: Enzymes, Mechanisms, and Control

Lipids and Proteins Are Associated in Biological Membranes

Nucleic Acids: How Structure Conveys Information

Biosynthesis of Nucleic Acids: Replication

Transcription of the Genetic Code: Biosynthesis of RNA

Protein Synthesis: Translation of the Genetic Message

Nucleic Acid Biotechnology Techniques

Viruses, Cancer, and Immunology

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism: Cellular Signaling

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How many ATPs can be netted from the complete oxidation of palmitate (C₁₆) to CO₂ & H₂O?