Question 1

Which are the three most common ketone bodies?

Accepted Answer

A)  Acetone, formaldehyde, acetoacetate. 
B)  Acetone, butyric acid and oxaloacetate. 
C)  Acetone, b-hydroxybutyrate and acetoacetate. 
D)  Acetone, b-hydroxybutyrate and oxaloacetate. 
E)  Acetocetate, b-hydroxybutyrate and oxaloacetate. 
A)  Acetone, formaldehyde, acetoacetate. 
B)  Acetone, butyric acid and oxaloacetate. 
C)  Acetone, b-hydroxybutyrate and acetoacetate. 
D)  Acetone, b-hydroxybutyrate and oxaloacetate. 
E)  Acetocetate, b-hydroxybutyrate and oxaloacetate.

Question 2

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

Accepted Answer

A) True 
 B)False

Question 3

Which of the following statements below about the activation of fatty acids is false?

Accepted Answer

A)  Activation involves the formation of a high energy thioester bond. 
B)  Activation is accompanied by hydrolysis of ATP to ADP and Pi. 
C)  Activation includes the formation of an acyl-adenylate intermediate. 
D)  Activation includes hydrolysis of ATP to produce AMP and PPi, with the further hydrolysis of PPi to drive the reaction to completion. 
A)  Activation involves the formation of a high energy thioester bond. 
B)  Activation is accompanied by hydrolysis of ATP to ADP and Pi. 
C)  Activation includes the formation of an acyl-adenylate intermediate. 
D)  Activation includes hydrolysis of ATP to produce AMP and PPi, with the further hydrolysis of PPi to drive the reaction to completion.

Question 4

The first true steroid synthesized in the steroid pathway is the following:

Accepted Answer

A)  Cholesterol. 
B)  Squalene 
C)  Lanosterol 
D)  Progesterone 
E)  Mevalonic acid 
A)  Cholesterol. 
B)  Squalene 
C)  Lanosterol 
D)  Progesterone 
E)  Mevalonic acid

Question 5

Phospholipases break down fats by

Accepted Answer

A)  adding a phosphate group to them. 
B)  reducing the double bonds to single bonds. 
C)  hydrolyzing them. 
D)  removing acetyl-CoA units. 
A)  adding a phosphate group to them. 
B)  reducing the double bonds to single bonds. 
C)  hydrolyzing them. 
D)  removing acetyl-CoA units.

Question 6

The reactions involved in b-oxidation of fatty acids include the following:   The correct order of these reactions is:

Accepted Answer

A)  1 2 3 4 
B)  4 3 2 1 
C)  3 2 4 1 
D)  2 4 3 1 
E)  1 4 3 2 
A)  1 2 3 4 
B)  4 3 2 1 
C)  3 2 4 1 
D)  2 4 3 1 
E)  1 4 3 2

Question 7

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

Question 8

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

Question 9

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 10

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 11

Lipoproteins are incorporated into the cell by a process called pinocytosis.

Accepted Answer

A) True 
 B)False

Question 12

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.

Question 13

The processing of one molecule of stearic acid (18 carbons) by b-oxidation

Accepted Answer

A)  requires 8 cycles of b-oxidation and produces 9 molecules of acetyl-CoA. 
B)  requires 8 cycles of b-oxidation and produces 8 molecules of acetyl-CoA. 
C)  requires 9 cycles of b-oxidation and produces 8 molecules of acetyl-CoA. 
D)  requires 9 cycles of b-oxidation and produces 9 molecules of acetyl-CoA. 
A)  requires 8 cycles of b-oxidation and produces 9 molecules of acetyl-CoA. 
B)  requires 8 cycles of b-oxidation and produces 8 molecules of acetyl-CoA. 
C)  requires 9 cycles of b-oxidation and produces 8 molecules of acetyl-CoA. 
D)  requires 9 cycles of b-oxidation and produces 9 molecules of acetyl-CoA.

Question 14

How many NAD+ are reduced in the degradation of palmitoyl-CoA to form eight molecules of acetyl-CoA?

Accepted Answer

A)  1 
B)  7 
C)  8 
D)  14 
E)  16 
A)  1 
B)  7 
C)  8 
D)  14 
E)  16

Question 15

If the bicarbonate used in malonyl-CoA synthesis were labeled with 14C in the biosynthesis of palmitate,where would the label be found in the reaction products?

Accepted Answer

A)  CO2 
B)  C-16 of palmitate 
C)  C-1 of palmitate 
D)  evenly distributed in palmitate 
A)  CO2 
B)  C-16 of palmitate 
C)  C-1 of palmitate 
D)  evenly distributed in palmitate

Question 16

A key intermediate in the catabolism of fatty acids with uneven numbers of carbon atoms is

Accepted Answer

A)  malonyl-CoA 
B)  propionyl-CoA 
C)  oxaloacetate 
D)  phosphoenolpyruvate 
A)  malonyl-CoA 
B)  propionyl-CoA 
C)  oxaloacetate 
D)  phosphoenolpyruvate

Question 17

The first committed precursor in the pathway for the synthesis of cholesterol is:

Accepted Answer

A)  Isoprene 
B)  Lanosterol 
C)  Mevalonic acid 
D)  Squalene 
E)  None of these is correct. 
A)  Isoprene 
B)  Lanosterol 
C)  Mevalonic acid 
D)  Squalene 
E)  None of these is correct.

Question 18

Cholesterol can be made in the body; however,some must still be eaten in the diet,since we cannot make enough to meet the demand.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following is not true regarding ketone bodies?

Accepted Answer

A)  Ketone bodies form during the catabolism of fats. 
B)  Ketone bodies are an effective means for weight loss, since the body will excrete them in the urine. 
C)  The first enzyme used in the production of ketone bodies is thiolase 
D)  Ketone bodies are always an alternative fuel in all tissues 
A)  Ketone bodies form during the catabolism of fats. 
B)  Ketone bodies are an effective means for weight loss, since the body will excrete them in the urine. 
C)  The first enzyme used in the production of ketone bodies is thiolase 
D)  Ketone bodies are always an alternative fuel in all tissues

Question 20

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

Exam 21: Lipid Metabolism

Which are the three most common ketone bodies?

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

Which of the following statements below about the activation of fatty acids is false?

The first true steroid synthesized in the steroid pathway is the following:

Phospholipases break down fats by

The reactions involved in b-oxidation of fatty acids include the following: The correct order of these reactions is:

The ultimate precursor of all the carbon atoms in steroids is

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

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

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

Lipoproteins are incorporated into the cell by a process called pinocytosis.

ACP used in fatty acid synthesis is an abbreviation for:

The processing of one molecule of stearic acid (18 carbons) by b-oxidation

How many NAD+ are reduced in the degradation of palmitoyl-CoA to form eight molecules of acetyl-CoA?

If the bicarbonate used in malonyl-CoA synthesis were labeled with 14C in the biosynthesis of palmitate,where would the label be found in the reaction products?

A key intermediate in the catabolism of fatty acids with uneven numbers of carbon atoms is

The first committed precursor in the pathway for the synthesis of cholesterol is:

Cholesterol can be made in the body; however,some must still be eaten in the diet,since we cannot make enough to meet the demand.

Which of the following is not true regarding ketone bodies?

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

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

Filters

How many NAD⁺ are reduced in the degradation of palmitoyl-CoA to form eight molecules of acetyl-CoA?

If the bicarbonate used in malonyl-CoA synthesis were labeled with ¹⁴C in the biosynthesis of palmitate,where would the label be found in the reaction products?