Question 1

Describe the first two steps of $\beta$ oxidation of saturated fatty acids. Indicate where any cofactors participate.

Accepted Answer

The first two steps of @#LAT-DLM& oxidation of sat

Question 2

Which statement is NOT true regarding the oxidation of 1 mol of palmitate (16:0) by the $\beta$-oxidation pathway?

Accepted Answer

A)  1 mol of ATP is needed. 
B)  8 mol of acetyl-CoA are formed. 
C)  8 mol of FADH2 are formed. 
D)  AMP and PPi are formed. 
E)  The reactions occur in the mitochondria. 
A)  1 mol of ATP is needed. 
B)  8 mol of acetyl-CoA are formed. 
C)  8 mol of FADH2 are formed. 
D)  AMP and PPi are formed. 
E)  The reactions occur in the mitochondria.

Question 3

Which form of a fatty acid is NOT found in the blood?

Accepted Answer

A)  acyl-CoA 
B)  free fatty acid bound to albumin 
C)  a component of a chylomicron 
D)  a component of a triacylglycerol 
E)  All of the answers are correct. 
A)  acyl-CoA 
B)  free fatty acid bound to albumin 
C)  a component of a chylomicron 
D)  a component of a triacylglycerol 
E)  All of the answers are correct.

Question 4

Explain the chemical reason why the addition of water across the double bond in the second step of $\beta$oxidation occurs with the OH adding at the $\beta$-carbon, not the $\alpha$-carbon. Also, how does addition at the $\beta$-carbon aid in the subsequent step(s) of $\beta$ oxidation?

Accepted Answer

The addition of water across the double

Question 5

The total degradation of a fatty acid with an odd number of carbons yields acetyl-CoA and another compound, X. Show the structure of X and describe the pathway by which it is converted into a citric acid cycle intermediate, including where any cofactors participate.

Accepted Answer

The compound X is propionyl-CoA. Propion

Question 6

The conversion of palmitoyl-CoA (16:0) to myristoyl-CoA (14:0) and 1 mol of acetyl-CoA by the $\beta$-oxidation pathway results in the net formation of:

Accepted Answer

A)  1 FADH2 and 1 NADH. 
B)  1 FADH2 and 1 NADPH. 
C)  1 FADH2, 1 NADH, and 1 ATP. 
D)  2 FADH2 and 2 NADH. 
E)  2 FADH2, 2 NADH, and 1 ATP. 
A)  1 FADH2 and 1 NADH. 
B)  1 FADH2 and 1 NADPH. 
C)  1 FADH2, 1 NADH, and 1 ATP. 
D)  2 FADH2 and 2 NADH. 
E)  2 FADH2, 2 NADH, and 1 ATP.

Question 7

Which enzyme is involved in activation of fatty acids in the cytosol?

Accepted Answer

A)  acyl-CoA synthetase 
B)  inorganic pyrophosphatase 
C)  carnitine acyltransferase I (CAT I) 
D)  both acyl-CoA synthetase and inorganic pyrophosphatase 
E)  both inorganic pyrophosphatase and carnitine acyltransferase I (CAT I) 
A)  acyl-CoA synthetase 
B)  inorganic pyrophosphatase 
C)  carnitine acyltransferase I (CAT I) 
D)  both acyl-CoA synthetase and inorganic pyrophosphatase 
E)  both inorganic pyrophosphatase and carnitine acyltransferase I (CAT I)

Question 8

Write a balanced equation for the $\beta$-oxidation of palmitoyl-CoA, a 16-carbon, fully saturated fatty acid, and indicate how much of each product is formed.

Accepted Answer

The balanced equation for the β-oxidatio

Question 9

In $ \omega $ oxidation, which enzyme acts on the $ \omega $ carbon?

Accepted Answer

A)  a mixed-function oxidase 
B)  alcohol dehydrogenase 
C)  aldehyde dehydrogenase 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  a mixed-function oxidase 
B)  alcohol dehydrogenase 
C)  aldehyde dehydrogenase 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 10

In $\beta$ oxidation, which cofactor is required for the conversion of a $\beta$-hydroxyacyl-CoA to a $\beta$-ketoacyl-CoA?

Accepted Answer

A)  NAD+ 
B)  FAD 
C)  H2O 
D)  CoA-SH 
E)  All of the answers are correct. 
A)  NAD+ 
B)  FAD 
C)  H2O 
D)  CoA-SH 
E)  All of the answers are correct.

Question 11

In mammals, which intermediate of carbohydrate metabolism CANNOT relieve ketosis?

Accepted Answer

A)  lactate 
B)  acetyl-CoA 
C)  fumarate 
D)  glycerol 
E)  succinyl-CoA 
A)  lactate 
B)  acetyl-CoA 
C)  fumarate 
D)  glycerol 
E)  succinyl-CoA

Question 12

For each two-carbon increase in the length of a saturated fatty acid chain, how many additional moles of ATP can be formed upon complete oxidation of one mole of the fatty acid to CO2 and H2O?

Accepted Answer

For each two-carbon increase in the leng

Question 13

The role of hormone-sensitive triacylglycerol lipase is to:

Accepted Answer

A)  hydrolyze lipids stored in the liver. 
B)  hydrolyze membrane phospholipids in hormone-producing cells. 
C)  hydrolyze triacylglycerols stored in adipose tissue. 
D)  synthesize lipids in adipose tissue. 
E)  synthesize triacylglycerols in the liver. 
A)  hydrolyze lipids stored in the liver. 
B)  hydrolyze membrane phospholipids in hormone-producing cells. 
C)  hydrolyze triacylglycerols stored in adipose tissue. 
D)  synthesize lipids in adipose tissue. 
E)  synthesize triacylglycerols in the liver.

Question 14

Which compound is an intermediate of the $\beta$oxidation of fatty acids?

Accepted Answer

A)  CH3-(CH2)20-CO-COOH 
B)  CH3-CH2-CO-CH2-CO-OPO32- 
C)  CH3-CH2-CO-CH2-OH 
D)  CH3-CH2-CO-CO-S-CoA 
E)  CH3-CO-CH2-CO-S-CoA 
A)  CH3-(CH2)20-CO-COOH 
B)  CH3-CH2-CO-CH2-CO-OPO32- 
C)  CH3-CH2-CO-CH2-OH 
D)  CH3-CH2-CO-CO-S-CoA 
E)  CH3-CO-CH2-CO-S-CoA

Question 15

Which statement(s) about acetoacetate and -hydroxybutyrate is/are FALSE?
1.     They can be used as a fuel by skeletal muscle.
2.     They are synthesized in the liver.
3.     They give rise to acetone.
4.     They require acetoacetyl-CoA for their synthesis.
5.     They may be regarded as water-soluble, transportable forms of citrate in the blood.

Accepted Answer

A) 	1 and 2 
B) 	3 only 
C) 	1 and 4 
D) 	4 and 5 
E) 	5 only 
A) 	1 and 2 
B) 	3 only 
C) 	1 and 4 
D) 	4 and 5 
E) 	5 only

Question 16

If an aerobic organism (e.g., the bacterium E. coli) were fed each of the following four compounds as a source of energy, the energy yield per mole from these molecules would be in the order:

Accepted Answer

A)  alanine > glucose > palmitate. 
B)  glucose > alanine > palmitate. 
C)  glucose > palmitate > alanine. 
D)  palmitate > alanine > glucose. 
E)  palmitate > glucose > alanine. 
A)  alanine > glucose > palmitate. 
B)  glucose > alanine > palmitate. 
C)  glucose > palmitate > alanine. 
D)  palmitate > alanine > glucose. 
E)  palmitate > glucose > alanine.

Question 17

In which cellular compartment is $ \omega $ oxidation carried out?

Accepted Answer

A)  the cytosol 
B)  the mitochondrial matrix 
C)  the mitochondrial intermembrane space 
D)  the endoplasmic reticulum 
E)  peroxisomes 
A)  the cytosol 
B)  the mitochondrial matrix 
C)  the mitochondrial intermembrane space 
D)  the endoplasmic reticulum 
E)  peroxisomes

Question 18

What is the role of lipoprotein lipase?

Accepted Answer

A)  It hydrolyzes triacylglycerols of plasma lipoproteins to supply fatty acids to various tissues. 
B)  It aids intestinal uptake of dietary fat. 
C)  It initiates intracellular lipid breakdown of lipoproteins. 
D)  It degrades lipoproteins in order to supply needed amino acids to various tissues. 
E)  It acts to regenerate lipoprotein particles in hepatocytes. 
A)  It hydrolyzes triacylglycerols of plasma lipoproteins to supply fatty acids to various tissues. 
B)  It aids intestinal uptake of dietary fat. 
C)  It initiates intracellular lipid breakdown of lipoproteins. 
D)  It degrades lipoproteins in order to supply needed amino acids to various tissues. 
E)  It acts to regenerate lipoprotein particles in hepatocytes.

Question 19

One of the steps in fatty acid oxidation in mitochondria involves the addition of water across a double bond. What is the next step in the process? Show structures and indicate where any cofactor(s) participate(s).

Accepted Answer

The next step in the process of fatty ac

Question 20

In the disease sprue, vitamin B12 (cobalamin) is poorly absorbed in the intestine, resulting in B12 deficiency. If each of the following fatty acids were in the diet, for which one would the process of fatty acid oxidation be MOST affected in a patient with sprue?

Accepted Answer

A)  CH3(CH2)10COOH 
B)  CH3(CH2)11COOH 
C)  CH3(CH2)12COOH 
D)  CH3(CH2)14COOH 
E)  CH3(CH2)18COOH 
A)  CH3(CH2)10COOH 
B)  CH3(CH2)11COOH 
C)  CH3(CH2)12COOH 
D)  CH3(CH2)14COOH 
E)  CH3(CH2)18COOH

Exam 17: Fatty Acid Catabolism

Describe the first two steps of β\betaβ oxidation of saturated fatty acids. Indicate where any cofactors participate.

Which statement is NOT true regarding the oxidation of 1 mol of palmitate (16:0) by the β\betaβ -oxidation pathway?

Which form of a fatty acid is NOT found in the blood?

The total degradation of a fatty acid with an odd number of carbons yields acetyl-CoA and another compound, X. Show the structure of X and describe the pathway by which it is converted into a citric acid cycle intermediate, including where any cofactors participate.

The conversion of palmitoyl-CoA (16:0) to myristoyl-CoA (14:0) and 1 mol of acetyl-CoA by the β\betaβ -oxidation pathway results in the net formation of:

Which enzyme is involved in activation of fatty acids in the cytosol?

Write a balanced equation for the β\betaβ -oxidation of palmitoyl-CoA, a 16-carbon, fully saturated fatty acid, and indicate how much of each product is formed.

In ω \omega ω oxidation, which enzyme acts on the ω \omega ω carbon?

In β\betaβ oxidation, which cofactor is required for the conversion of a β\betaβ -hydroxyacyl-CoA to a β\betaβ -ketoacyl-CoA?

In mammals, which intermediate of carbohydrate metabolism CANNOT relieve ketosis?

For each two-carbon increase in the length of a saturated fatty acid chain, how many additional moles of ATP can be formed upon complete oxidation of one mole of the fatty acid to CO2 and H2O?

The role of hormone-sensitive triacylglycerol lipase is to:

Which compound is an intermediate of the β\betaβ oxidation of fatty acids?

If an aerobic organism (e.g., the bacterium E. coli) were fed each of the following four compounds as a source of energy, the energy yield per mole from these molecules would be in the order:

In which cellular compartment is ω \omega ω oxidation carried out?

What is the role of lipoprotein lipase?

One of the steps in fatty acid oxidation in mitochondria involves the addition of water across a double bond. What is the next step in the process? Show structures and indicate where any cofactor(s) participate(s).

In the disease sprue, vitamin B12 (cobalamin) is poorly absorbed in the intestine, resulting in B12 deficiency. If each of the following fatty acids were in the diet, for which one would the process of fatty acid oxidation be MOST affected in a patient with sprue?

The Foundations of Biochemistry

Water

Amino Acids, Peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Enzymes

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

DNA-Based Information Technologies

Lipids

Biological Membranes and Transport

Biosignaling

Bioenergetics and Biochemical Reaction Types

Glycolysis, Gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, Nucleotides, and Related Molecules

Hormonal Regulation and Integration of Mammalian Metabolism

Genes and Chromosomes

DNA Metabolism

RNA Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

Describe the first two steps of $\beta$ oxidation of saturated fatty acids. Indicate where any cofactors participate.

Which statement is NOT true regarding the oxidation of 1 mol of palmitate (16:0) by the $\beta$ -oxidation pathway?

The conversion of palmitoyl-CoA (16:0) to myristoyl-CoA (14:0) and 1 mol of acetyl-CoA by the $\beta$ -oxidation pathway results in the net formation of:

Write a balanced equation for the $\beta$ -oxidation of palmitoyl-CoA, a 16-carbon, fully saturated fatty acid, and indicate how much of each product is formed.

In $\omega$ oxidation, which enzyme acts on the $\omega$ carbon?

In $\beta$ oxidation, which cofactor is required for the conversion of a $\beta$ -hydroxyacyl-CoA to a $\beta$ -ketoacyl-CoA?

For each two-carbon increase in the length of a saturated fatty acid chain, how many additional moles of ATP can be formed upon complete oxidation of one mole of the fatty acid to CO₂ and H₂O?

Which compound is an intermediate of the $\beta$ oxidation of fatty acids?

In which cellular compartment is $\omega$ oxidation carried out?

In the disease sprue, vitamin B₁₂ (cobalamin) is poorly absorbed in the intestine, resulting in B₁₂ deficiency. If each of the following fatty acids were in the diet, for which one would the process of fatty acid oxidation be MOST affected in a patient with sprue?