Question 1

The human lipoproteins with the lowest density are

Accepted Answer

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

Question 2

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 3

When the blood contains a high concentration of LDLs, the cells respond by making fewer receptors to react with the LDL.

Accepted Answer

A) True 
 B)False

Question 4

Which of the following is true concerning phospholipases?

Accepted Answer

A)  Many snake venoms contain phospholipases 
B)  Phospholipase D is a component in some spider venoms 
C)  Phospholipases in snake venoms can lead to the lysing of blood cells 
D)  All of these 
A)  Many snake venoms contain phospholipases 
B)  Phospholipase D is a component in some spider venoms 
C)  Phospholipases in snake venoms can lead to the lysing of blood cells 
D)  All of these

Question 5

Fatty acid catabolism is called β-oxidation, since the second or β carbon from the carboxyl group is the site of oxidation.

Accepted Answer

A) True 
 B)False

Question 6

During fatty acid synthesis, the growing fatty acid is always bound to a protein.

Accepted Answer

A) True 
 B)False

Question 7

The β-oxidation of unsaturated fatty acids requires additional enzymes to isomerize the double bonds.

Accepted Answer

A) True 
 B)False

Question 8

What effect do high concentrations of ketone bodies have on blood pH?

Accepted Answer

A)  They tend to lower blood pH. 
B)  They tend to increase blood pH. 
C)  They have no effect on blood pH. 
A)  They tend to lower blood pH. 
B)  They tend to increase blood pH. 
C)  They have no effect on blood pH.

Question 9

Which are the three most common ketone bodies?

Accepted Answer

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

Question 10

A key intermediate in the formation of "ketone bodies" is

Accepted Answer

A)  succinyl-CoA 
B)  methyl malonyl-CoA 
C)  propionyl-CoA 
D)  acetoacetyl-CoA 
A)  succinyl-CoA 
B)  methyl malonyl-CoA 
C)  propionyl-CoA 
D)  acetoacetyl-CoA

Question 11

The oxidation of unsaturated fatty acids specifically requires

Accepted Answer

A)  a cis-trans isomerase and a reductase. 
B)  a cis-trans isomerase and a dehydrogenase. 
C)  a dehydrogenase and a reductase. 
D)  a dehydrogenase and a hydrase. 
E)  none of these 
A)  a cis-trans isomerase and a reductase. 
B)  a cis-trans isomerase and a dehydrogenase. 
C)  a dehydrogenase and a reductase. 
D)  a dehydrogenase and a hydrase. 
E)  none of these

Question 12

Where in the cell does fatty acid synthesis occur?

Accepted Answer

A)  Cytoplasm. 
B)  Outer mitochondrial membrane. 
C)  Mitochondrial intermembrane space. 
D)  Inner mitochondrial membrane. 
E)  Mitochondrial matrix. 
A)  Cytoplasm. 
B)  Outer mitochondrial membrane. 
C)  Mitochondrial intermembrane space. 
D)  Inner mitochondrial membrane. 
E)  Mitochondrial matrix.

Question 13

The bond linking a fatty acid to coenzyme A is

Accepted Answer

A)  an ester. 
B)  a thioester. 
C)  an anhydride. 
D)  an ether. 
E)  none of these 
A)  an ester. 
B)  a thioester. 
C)  an anhydride. 
D)  an ether. 
E)  none of these

Question 14

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 15

Which of the following is not associated with coronary heart disease?

Accepted Answer

A)  high relative levels of HDLs 
B)  high levels of LDLs 
C)  absence or dysfunction of LDL receptors 
D)  serum cholesterol levels of 300 mg/dl or higher 
A)  high relative levels of HDLs 
B)  high levels of LDLs 
C)  absence or dysfunction of LDL receptors 
D)  serum cholesterol levels of 300 mg/dl or higher

Question 16

Compared to β-oxidation, fatty acid synthesis requires this extra vitamin or cofactor.

Accepted Answer

A)  Biotin 
B)  Riboflavin 
C)  Niacin 
D)  Pantothenic acid 
E)  All of these are used in both pathways. 
A)  Biotin 
B)  Riboflavin 
C)  Niacin 
D)  Pantothenic acid 
E)  All of these are used in both pathways.

Question 17

Reduction reactions during fatty acid synthesis utilize

Accepted Answer

A)  FADH2. 
B)  NADH. 
C)  NADPH. 
D)  FADH2 and NADH. 
E)  FADH2 and NADPH. 
A)  FADH2. 
B)  NADH. 
C)  NADPH. 
D)  FADH2 and NADH. 
E)  FADH2 and NADPH.

Question 18

How many cycles of β-oxidation are required to convert stearic acid (18 carbons) to 9 acetyl-CoAs?

Accepted Answer

A)  6 
B)  8 
C)  9 
D)  18 
E)  none of these 
A)  6 
B)  8 
C)  9 
D)  18 
E)  none of these

Question 19

The committed step in cholesterol biosynthesis is catalyzed by

Accepted Answer

A)  HMG-CoA synthase 
B)  HMG-CoA reductase 
C)  mevalonate kinase 
D)  squalene monooxygenase 
A)  HMG-CoA synthase 
B)  HMG-CoA reductase 
C)  mevalonate kinase 
D)  squalene monooxygenase

Question 20

When an acyl group is being transferred from the cytosol to the mitochondria for oxidation, the order of the enzymes it encounters is:

Accepted Answer

A)  CPT-I: Carnitine Translocase: CPT-II 
B)  Carnitine Translocase: CPT-I: CPT-II 
C)  CPT-II: Carnitine Translocase: CPT-I 
D)  none of these 
A)  CPT-I: Carnitine Translocase: CPT-II 
B)  Carnitine Translocase: CPT-I: CPT-II 
C)  CPT-II: Carnitine Translocase: CPT-I 
D)  none of these

Exam 21: Lipid Metabolism

The human lipoproteins with the lowest density are

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

When the blood contains a high concentration of LDLs, the cells respond by making fewer receptors to react with the LDL.

Which of the following is true concerning phospholipases?

Fatty acid catabolism is called β-oxidation, since the second or β carbon from the carboxyl group is the site of oxidation.

During fatty acid synthesis, the growing fatty acid is always bound to a protein.

The β-oxidation of unsaturated fatty acids requires additional enzymes to isomerize the double bonds.

What effect do high concentrations of ketone bodies have on blood pH?

Which are the three most common ketone bodies?

A key intermediate in the formation of "ketone bodies" is

The oxidation of unsaturated fatty acids specifically requires

Where in the cell does fatty acid synthesis occur?

The bond linking a fatty acid to coenzyme A is

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

Which of the following is not associated with coronary heart disease?

Compared to β-oxidation, fatty acid synthesis requires this extra vitamin or cofactor.

Reduction reactions during fatty acid synthesis utilize

How many cycles of β-oxidation are required to convert stearic acid (18 carbons) to 9 acetyl-CoAs?

The committed step in cholesterol biosynthesis is catalyzed by

When an acyl group is being transferred from the cytosol to the mitochondria for oxidation, the order of the enzymes it encounters 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

Filters

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