Question 1

The acetyl-CoA for fatty acid synthesis comes from the

Accepted Answer

A)  breakdown of fats. 
B)  TCA cycle. 
C)  mitochondria via the citrate shuttle. 
D)  breakdown of cytoplasmic pyruvate. 
A)  breakdown of fats. 
B)  TCA cycle. 
C)  mitochondria via the citrate shuttle. 
D)  breakdown of cytoplasmic pyruvate. C

Question 2

What is the name of the enzyme that adds another carbon atom to propionyl-CoA in the degradation of odd-chain fatty acids?

Accepted Answer

Propionyl-CoA carboxylase

Question 3

All of the following genes are activated by the interaction of the SREBP with the SRE, EXCEPT for

Accepted Answer

A)  HMG-CoA reductase. 
B)  LDL receptor. 
C)  HMG-CoA synthase. 
D)  cholesterol esterase. 
A)  HMG-CoA reductase. 
B)  LDL receptor. 
C)  HMG-CoA synthase. 
D)  cholesterol esterase. D

Question 4

Describe the metabolic conditions under which ketone bodies are produced.

Accepted Answer

When carbohydrate levels run low, typica

Question 5

The following fatty acid __________ be metabolized by _.

Accepted Answer

A)  will; being run through the $\beta$-oxidation pathway until the double bond is isomerized for the pathway to continue 
B)  will not; not being recognized by $\beta$-oxidation pathway enzymes 
C)  will not; entering the pathway as normal but eventually inhibiting the enzymes 
D)  will; being run through the $\beta$-oxidation pathway as normal 
A)  will; being run through the $\beta$-oxidation pathway until the double bond is isomerized for the pathway to continue 
B)  will not; not being recognized by $\beta$-oxidation pathway enzymes 
C)  will not; entering the pathway as normal but eventually inhibiting the enzymes 
D)  will; being run through the $\beta$-oxidation pathway as normal

Question 6

Cholesterol biosynthesis and cholesterol uptake is stimulated by

Accepted Answer

A)  the binding of SREs to cholesterol uptake genes. 
B)  the binding of SREBPs to SREs and activating the transcription of cholesterol synthesizing genes. 
C)  increased levels of cholesterol binding to the SREBPs. 
D)  the uptake of LDLs through the LDL receptor. 
A)  the binding of SREs to cholesterol uptake genes. 
B)  the binding of SREBPs to SREs and activating the transcription of cholesterol synthesizing genes. 
C)  increased levels of cholesterol binding to the SREBPs. 
D)  the uptake of LDLs through the LDL receptor.

Question 7

Which is true of the acyl carrier protein (ACP)?

Accepted Answer

A)  It transports the fatty acid chain during oxidation and synthesis. 
B)  It directs the growing fatty acid chain from one enzyme active site to another in the fatty acid synthesis pathway. 
C)  It requires ATP for proper function. 
D)  It catalyzes the delivery of fatty acyl chains from the mitochondria to the cytosol. 
A)  It transports the fatty acid chain during oxidation and synthesis. 
B)  It directs the growing fatty acid chain from one enzyme active site to another in the fatty acid synthesis pathway. 
C)  It requires ATP for proper function. 
D)  It catalyzes the delivery of fatty acyl chains from the mitochondria to the cytosol.

Question 8

All of the following are metabolic fates of cholesterol EXCEPT

Accepted Answer

A)  the majority of cholesterol is catabolized to bile salts. 
B)  cholesterol may be present in membranes. 
C)  cholesterol is a precursor for nucleotides. 
D)  steroids are derived from cholesterol. 
A)  the majority of cholesterol is catabolized to bile salts. 
B)  cholesterol may be present in membranes. 
C)  cholesterol is a precursor for nucleotides. 
D)  steroids are derived from cholesterol.

Question 9

Which one of the following lipoproteins functions to transport cholesterol from the peripheral tissues to the liver?

Accepted Answer

A)  VLDL 
B)  LDL 
C)  HDL 
D)  chylomicron 
A)  VLDL 
B)  LDL 
C)  HDL 
D)  chylomicron

Question 10

In order for a fatty acyl-CoA to be moved into the mitochondria for $\beta$-oxidation, it must be

Accepted Answer

A)  transported by the carnitine-acylcarnitine translocase. 
B)  activated by ATP. 
C)  reduced by NADH and FADH2. 
D)  hydrolyzed into acetyl-coA fragments. 
A)  transported by the carnitine-acylcarnitine translocase. 
B)  activated by ATP. 
C)  reduced by NADH and FADH2. 
D)  hydrolyzed into acetyl-coA fragments.

Question 11

Identify the molecular components of the following lipoprotein.

Accepted Answer

(A) Cholesterol, (B) triacylgl

Question 12

During the conversion of VLDL to IDL, the

Accepted Answer

A)  IDL becomes increasingly enriched in cholesterol. 
B)  core of IDL becomes increasingly enriched in TAGs. 
C)  LDL intermediate is formed. 
D)  IDL becomes depleted in protein. 
A)  IDL becomes increasingly enriched in cholesterol. 
B)  core of IDL becomes increasingly enriched in TAGs. 
C)  LDL intermediate is formed. 
D)  IDL becomes depleted in protein.

Question 13

How many more enzymes does the oxidation of oleoyl-CoA (18:1) require than the oxidation of stearoyl-CoA (18:0)?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  3 
A)  0 
B)  1 
C)  2 
D)  3

Question 14

What enzyme class catalyzes the following reaction?

Accepted Answer

A)  ligase 
B)  hydratase 
C)  transferase 
D)  oxidoreductase 
A)  ligase 
B)  hydratase 
C)  transferase 
D)  oxidoreductase

Question 15

How many more passes through $\beta$-oxidation does the saturated fat stearic acid (18:0) require, compared with the monounsaturated fat oleic acid (18:1)?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  17 
A)  0 
B)  1 
C)  2 
D)  17

Question 16

What enzyme is activated by HDL to release cholesterol from the cell membranes of peripheral tissues?

Accepted Answer

A)  phosphatidylcholine esterase 
B)  HDL apolipase 
C)  cholesterol esterase 
D)  lecithin-cholesterol acyltransferase 
A)  phosphatidylcholine esterase 
B)  HDL apolipase 
C)  cholesterol esterase 
D)  lecithin-cholesterol acyltransferase

Question 17

The smallest precursor molecule cholesterol is derived from

Accepted Answer

A)  squalene. 
B)  isoprene. 
C)  arachidonic acid. 
D)  acetyl-CoA. 
A)  squalene. 
B)  isoprene. 
C)  arachidonic acid. 
D)  acetyl-CoA.

Question 18

For every two carbons that are added to a growing fatty acid chain in the fatty acid synthesis pathway, __________ ATPs and __________ NADPHs are required.

Accepted Answer

A)  0; 1 
B)  1; 2 
C)  2; 1 
D)  0; 2 
A)  0; 1 
B)  1; 2 
C)  2; 1 
D)  0; 2

Question 19

Diagram the process by which the palmitoyl-CoA molecule moves from the cytosol into the mitochondria for degradation.

Accepted Answer

The answer of Diagram the process by which the palmitoyl-CoA...

Question 20

What cofactor, common to carboxylase enzymes, is used by acetyl-CoA carboxylase?

Accepted Answer

A)  NADPH 
B)  FAD 
C)  biotin 
D)  pyridoxal phosphate 
A)  NADPH 
B)  FAD 
C)  biotin 
D)  pyridoxal phosphate

Exam 16: Lipid Metabolism

The acetyl-CoA for fatty acid synthesis comes from the

What is the name of the enzyme that adds another carbon atom to propionyl-CoA in the degradation of odd-chain fatty acids?

All of the following genes are activated by the interaction of the SREBP with the SRE, EXCEPT for

Describe the metabolic conditions under which ketone bodies are produced.

The following fatty acid __________ be metabolized by _.

Cholesterol biosynthesis and cholesterol uptake is stimulated by

Which is true of the acyl carrier protein (ACP)?

All of the following are metabolic fates of cholesterol EXCEPT

Which one of the following lipoproteins functions to transport cholesterol from the peripheral tissues to the liver?

In order for a fatty acyl-CoA to be moved into the mitochondria for β\betaβ -oxidation, it must be

Identify the molecular components of the following lipoprotein.

During the conversion of VLDL to IDL, the

How many more enzymes does the oxidation of oleoyl-CoA (18:1) require than the oxidation of stearoyl-CoA (18:0)?

What enzyme class catalyzes the following reaction?

How many more passes through β\betaβ -oxidation does the saturated fat stearic acid (18:0) require, compared with the monounsaturated fat oleic acid (18:1)?

What enzyme is activated by HDL to release cholesterol from the cell membranes of peripheral tissues?

The smallest precursor molecule cholesterol is derived from

For every two carbons that are added to a growing fatty acid chain in the fatty acid synthesis pathway, __________ ATPs and __________ NADPHs are required.

Diagram the process by which the palmitoyl-CoA molecule moves from the cytosol into the mitochondria for degradation.

What cofactor, common to carboxylase enzymes, is used by acetyl-CoA carboxylase?

Principles of Biochemistry

Physical Biochemistry: Energy Conversion, Water, and Membranes

Nucleic Acid Structure and Function

Protein Structure

Methods in Protein Biochemistry

Protein Function

Enzyme Mechanisms

Cell Signaling Systems

Glycolysis: a Paradigm of Metabolic Regulation

The Citrate Cycle

Oxidative Phosphorylation

Photosynthesis

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Amino Acid Metabolism

Nucleotide Metabolism

Metabolic Integration

DNA Replication, Repair, and Recombination

RNA Synthesis, Processing, and Gene Silencing

Protein Synthesis, Posttranslational Modification, and Transport

Gene Regulation

Filters

In order for a fatty acyl-CoA to be moved into the mitochondria for $\beta$ -oxidation, it must be

How many more passes through $\beta$ -oxidation does the saturated fat stearic acid (18:0) require, compared with the monounsaturated fat oleic acid (18:1)?

For every two carbons that are added to a growing fatty acid chain in the fatty acid synthesis pathway, ATPs and NADPHs are required.