Question 1

Isopentenyl pyrophosphate is the precursor for which of the following?

Accepted Answer

A)  terpenes 
B)  vitamin K 
C)  quinones 
D)  All of the above 
E)  None of the above 
A)  terpenes 
B)  vitamin K 
C)  quinones 
D)  All of the above 
E)  None of the above D

Question 2

Double bonds positioned farther than nine carbons from the carboxyl end of fatty acids occur only in vertebrates.

Accepted Answer

A) True 
 B)False  False

Question 3

Chylomicrons are found in high concentrations in the blood only during fasting when lipids from adipose tissue are mobilized.

Accepted Answer

A) True 
 B)False  False

Question 4

What is the main function of the carnitine shuttle system?

Accepted Answer

A)  To transport fatty acids into the mitochondrion. 
B)  To transport newly synthesized sphingolipids to the blood. 
C)  To carry cholesterol from its site of synthesis in the endoplasmic reticulum to the plasma membrane. 
D)  To aid in the assembly of chylomicrons. 
A)  To transport fatty acids into the mitochondrion. 
B)  To transport newly synthesized sphingolipids to the blood. 
C)  To carry cholesterol from its site of synthesis in the endoplasmic reticulum to the plasma membrane. 
D)  To aid in the assembly of chylomicrons.

Question 5

The cyclooxygenase-hydroperoxidase pathway is a precursor for each of the following except

Accepted Answer

A)  thromboxane A2. 
B)  prostacyclin. 
C)  prostaglandins. 
D)  epinephrine. 
A)  thromboxane A2. 
B)  prostacyclin. 
C)  prostaglandins. 
D)  epinephrine.

Question 6

The conversion of the fatty acid palmitate C16) to carbon dioxide via β-oxidation, the citric acid cycle and oxidative phosphorylation yield approximately ATP equivalents.

Accepted Answer

A)  3 
B)  32 
C)  106 
D)  800 
A)  3 
B)  32 
C)  106 
D)  800

Question 7

Which sphingolipid is a precursor for all other types of sphingolipids?

Accepted Answer

A)  sphingomyelin 
B)  cerebroside 
C)  ganglioside 
D)  ceramide 
A)  sphingomyelin 
B)  cerebroside 
C)  ganglioside 
D)  ceramide

Question 8

The structure shown below is .

Accepted Answer

A)  taurocholate 
B)  glycerophospholipid 
C)  carnitine 
D)  lysophosphoglyceride 
A)  taurocholate 
B)  glycerophospholipid 
C)  carnitine 
D)  lysophosphoglyceride

Question 9

Fatty acids are oxidized in the .

Accepted Answer

A)  mitochondrial matrix 
B)  cytosol 
C)  endoplasmic reticulum 
D)  mitochondrial inner membrane space 
A)  mitochondrial matrix 
B)  cytosol 
C)  endoplasmic reticulum 
D)  mitochondrial inner membrane space

Question 10

Which of the following is a true statement for fatty acid oxidation?

Accepted Answer

A)  It occurs in the cytosol. 
B)  Oxidation requires a three carbon substrate, which transfers a two-carbon unit to the chain. 
C)  Both NADH and QH2 are produced. 
D)  None of the above 
A)  It occurs in the cytosol. 
B)  Oxidation requires a three carbon substrate, which transfers a two-carbon unit to the chain. 
C)  Both NADH and QH2 are produced. 
D)  None of the above

Question 11

To oxidize the fatty acid molecule shown below, what enzymes) are needed in addition to the enzymes needed for β-oxidation?

Accepted Answer

A)  enoyl-CoA isomerase only 
B)  2,4-dienoyl-CoA reductase only 
C)  both enoyl-CoA isomerase and 2,4-dienoyl-CoA reductase 
D)  No additional enzymes are needed besides the normal ones for β-oxidation. 
A)  enoyl-CoA isomerase only 
B)  2,4-dienoyl-CoA reductase only 
C)  both enoyl-CoA isomerase and 2,4-dienoyl-CoA reductase 
D)  No additional enzymes are needed besides the normal ones for β-oxidation.

Question 12

Eicosanoids are not like hormones in that they

Accepted Answer

A)  can alter blood flow. 
B)  act in the area where they are formed. 
C)  can mediate inflammation and swelling. 
D)  are chemically diverse. 
A)  can alter blood flow. 
B)  act in the area where they are formed. 
C)  can mediate inflammation and swelling. 
D)  are chemically diverse.

Question 13

Elevated levels of the hormone stimulate the conversion of triacylglycerols stored in adipose cells to free fatty acids and monoacylglycerols to provide energy when carbohydrate stores are depleted.

Accepted Answer

A)  insulin 
B)  glucagon 
C)  epinephrine 
D)  ergosterol 
A)  insulin 
B)  glucagon 
C)  epinephrine 
D)  ergosterol

Question 14

Why are triacylglycerols able to provide more energy than carbohydrates gram for gram)?

Accepted Answer

A)  The triacylglycerols have an extremely high group transfer potential. 
B)  The carbohydrates are already in a more oxidized state than the triacylglycerols. 
C)  The carbohydrates contain fewer carbon-carbon bonds. 
D)  The triacylglycerols are less soluble in water than the carbohydrates. 
A)  The triacylglycerols have an extremely high group transfer potential. 
B)  The carbohydrates are already in a more oxidized state than the triacylglycerols. 
C)  The carbohydrates contain fewer carbon-carbon bonds. 
D)  The triacylglycerols are less soluble in water than the carbohydrates.

Question 15

To oxidize the fatty acid molecule shown below, what enzymes) isare) needed in addition to the enzymes needed for β-oxidation?

Accepted Answer

A)  enoyl-CoA isomerase only 
B)  2,4-dienoyl-CoA reductase only 
C)  both enoyl-CoA isomerase and 2,4-dienoyl-CoA reductase 
D)  No additional enzymes are needed besides the normal ones for β-oxidation. 
A)  enoyl-CoA isomerase only 
B)  2,4-dienoyl-CoA reductase only 
C)  both enoyl-CoA isomerase and 2,4-dienoyl-CoA reductase 
D)  No additional enzymes are needed besides the normal ones for β-oxidation.

Question 16

How many cycles of β-oxidation are required to completely process a saturated C18 fatty acid?

Accepted Answer

A)  6 
B)  8 
C)  9 
D)  18 
A)  6 
B)  8 
C)  9 
D)  18

Question 17

Each of the following is a principle hormonal regulator of fatty acid metabolism, except

Accepted Answer

A)  glucagon. 
B)  adrenaline. 
C)  insulin. 
D)  epinephrine. 
A)  glucagon. 
B)  adrenaline. 
C)  insulin. 
D)  epinephrine.

Question 18

In mammals the oxidation of fatty acids produces a two-carbon product and the synthesis of fatty acids begins with a two-carbon substrate.

Accepted Answer

A) True 
 B)False

Question 19

How many QH2 and NADH are produced by one round of the β-oxidation pathway?

Accepted Answer

A)  1 each 
B)  1 QH2 and 2 NADH 
C)  2 each 
D)  2 QH2 and 1 NADH 
A)  1 each 
B)  1 QH2 and 2 NADH 
C)  2 each 
D)  2 QH2 and 1 NADH

Question 20

Why is poor plasmalogen synthesis potentially fatal?

Accepted Answer

A)  The nervous system is affected because plasmalogens are important constituents of the myelin sheath. 
B)  The mitochondria will not function properly due to lack of plasmalogen produced cardiolipin. 
C)  Poor nutrient absorption will occur in the small intestine where plasmalogens aid with the absorption of lipid-soluble vitamins and other hydrophobic substances. 
D)  Protein synthesis is affected due to the inability of plasmalogens binding ribosomes to the endoplasmic reticulum. 
A)  The nervous system is affected because plasmalogens are important constituents of the myelin sheath. 
B)  The mitochondria will not function properly due to lack of plasmalogen produced cardiolipin. 
C)  Poor nutrient absorption will occur in the small intestine where plasmalogens aid with the absorption of lipid-soluble vitamins and other hydrophobic substances. 
D)  Protein synthesis is affected due to the inability of plasmalogens binding ribosomes to the endoplasmic reticulum.

Exam 16: Lipid Metabolism

Isopentenyl pyrophosphate is the precursor for which of the following?

Double bonds positioned farther than nine carbons from the carboxyl end of fatty acids occur only in vertebrates.

Chylomicrons are found in high concentrations in the blood only during fasting when lipids from adipose tissue are mobilized.

What is the main function of the carnitine shuttle system?

The cyclooxygenase-hydroperoxidase pathway is a precursor for each of the following except

The conversion of the fatty acid palmitate C16) to carbon dioxide via β-oxidation, the citric acid cycle and oxidative phosphorylation yield approximately ATP equivalents.

Which sphingolipid is a precursor for all other types of sphingolipids?

The structure shown below is .

Fatty acids are oxidized in the .

Which of the following is a true statement for fatty acid oxidation?

To oxidize the fatty acid molecule shown below, what enzymes) are needed in addition to the enzymes needed for β-oxidation?

Eicosanoids are not like hormones in that they

Elevated levels of the hormone stimulate the conversion of triacylglycerols stored in adipose cells to free fatty acids and monoacylglycerols to provide energy when carbohydrate stores are depleted.

Why are triacylglycerols able to provide more energy than carbohydrates gram for gram)?

To oxidize the fatty acid molecule shown below, what enzymes) isare) needed in addition to the enzymes needed for β-oxidation?

How many cycles of β-oxidation are required to completely process a saturated C18 fatty acid?

Each of the following is a principle hormonal regulator of fatty acid metabolism, except

In mammals the oxidation of fatty acids produces a two-carbon product and the synthesis of fatty acids begins with a two-carbon substrate.

How many QH2 and NADH are produced by one round of the β-oxidation pathway?

Why is poor plasmalogen synthesis potentially fatal?

Introduction to Biochemistry

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Coenzymes and Vitamins

Carbohydrates

Lipids and Membranes

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

Dna Replication, Repair, and Recombination

Transcription and Rna Processing

Protein Synthesis

Recombinant Dna Technology

Filters

The conversion of the fatty acid palmitate C₁₆) to carbon dioxide via β-oxidation, the citric acid cycle and oxidative phosphorylation yield approximately ATP equivalents.

How many cycles of β-oxidation are required to completely process a saturated C₁₈fatty acid?

How many QH₂and NADH are produced by one round of the β-oxidation pathway?