Question 1

The first chemical step in the breakdown of triacylglycerols is

Accepted Answer

A) complete hydrolysis to fatty acids and glycerols. 
B) partial hydrolysis to fatty acids,phosphates,and diacylglycerols. 
C) oxidation of alcohol groups to carbonyls. 
D) rearrangement to cholesterol derivatives. 
E) none of the above 
A) complete hydrolysis to fatty acids and glycerols. 
B) partial hydrolysis to fatty acids,phosphates,and diacylglycerols. 
C) oxidation of alcohol groups to carbonyls. 
D) rearrangement to cholesterol derivatives. 
E) none of the above A

Question 2

If lipid catabolism produces more acetyl-CoA than the citric acid cycle can consume,but there is still a need for energy,the process of ________ takes over.

Accepted Answer

A) gluconeogenesis 
B) ketogenesis 
C) lipogenesis 
D) steroid synthesis 
E) transamination 
A) gluconeogenesis 
B) ketogenesis 
C) lipogenesis 
D) steroid synthesis 
E) transamination B

Question 3

Chylomicrons are the least dense of all the lipoprotein/lipid combinations because

Accepted Answer

A) their lipoproteins nest together easily. 
B) they have a high ratio of cholesterol to triacylglycerols. 
C) they have the highest proportion of less dense lipid molecules. 
D) there are many carbohydrate groups included in the external structure. 
E) their amino acids are mostly hydrophobic. 
A) their lipoproteins nest together easily. 
B) they have a high ratio of cholesterol to triacylglycerols. 
C) they have the highest proportion of less dense lipid molecules. 
D) there are many carbohydrate groups included in the external structure. 
E) their amino acids are mostly hydrophobic. C

Question 4

Which factor is the same in both lipogenesis and β-oxidation of fatty acids?

Accepted Answer

A) They occur in the same location in the cell. 
B) They use the same enzymes. 
C) They both involve NADPH and FAD. 
D) They both depend on coenzyme A. 
E) They both occur two carbon atoms at a time. 
A) They occur in the same location in the cell. 
B) They use the same enzymes. 
C) They both involve NADPH and FAD. 
D) They both depend on coenzyme A. 
E) They both occur two carbon atoms at a time.

Question 5

The molecule that is a precursor to the other ketone bodies is

Accepted Answer

A) acetone. 
B) acetoacetate. 
C) 3-hydroxybutyrate. 
D) malonyl-ACP. 
E) malonyl-CoA. 
A) acetone. 
B) acetoacetate. 
C) 3-hydroxybutyrate. 
D) malonyl-ACP. 
E) malonyl-CoA.

Question 6

Which is the correct term for the micelle-like structures which transport triglycerides in the bloodstream after digestion?

Accepted Answer

A) very low-density lipoproteins 
B) low-density lipoproteins 
C) high-density lipoproteins 
D) liposomes 
E) chylomicrons 
A) very low-density lipoproteins 
B) low-density lipoproteins 
C) high-density lipoproteins 
D) liposomes 
E) chylomicrons

Question 7

What is the role of a chylomicron?

Accepted Answer

A) to transport triacylglycerols in the bloodstream 
B) to synthesize cholesterol and other steroids 
C) to move triacylglycerol across the cell membrane 
D) to store excess triacylglycerols until they are needed 
E) to transport acetyl-CoA from the cytosol to the mitochondria 
A) to transport triacylglycerols in the bloodstream 
B) to synthesize cholesterol and other steroids 
C) to move triacylglycerol across the cell membrane 
D) to store excess triacylglycerols until they are needed 
E) to transport acetyl-CoA from the cytosol to the mitochondria

Question 8

High density lipoproteins contain a greater amount of ________ than do low density lipoproteins.

Accepted Answer

A) protein 
B) lipids 
C) triglycerides 
D) cholesterol 
E) fatty acids 
A) protein 
B) lipids 
C) triglycerides 
D) cholesterol 
E) fatty acids

Question 9

Where do the first chemical changes in the digestion of dietary fats take place?

Accepted Answer

A) mouth 
B) stomach 
C) small intestine 
D) large intestine 
E) liver 
A) mouth 
B) stomach 
C) small intestine 
D) large intestine 
E) liver

Question 10

Digestion of lipids begins in the ________,in a process catalyzed by ________.

Accepted Answer

A) mouth;salivary amylase 
B) stomach;hydrochloric acid 
C) small intestine;pancreatic lipases 
D) large intestines;bile acids 
E) adipocytes;triacylglycerol lipase 
A) mouth;salivary amylase 
B) stomach;hydrochloric acid 
C) small intestine;pancreatic lipases 
D) large intestines;bile acids 
E) adipocytes;triacylglycerol lipase

Question 11

Which molecule is associated with transport of fatty acids into the mitochondrial matrix?

Accepted Answer

A) glycerol 3-phosphate 
B) NADH 
C) coenzyme A 
D) carnitine 
E) fatty acids 
A) glycerol 3-phosphate 
B) NADH 
C) coenzyme A 
D) carnitine 
E) fatty acids

Question 12

Which of the ketone bodies is as an energy source for heart and muscle tissue during the early stages of starvation?

Accepted Answer

A) acetoacetate 
B) acetone 
C) 3-hydroxybutyrate 
D) All of these are used. 
E) None of these are used. 
A) acetoacetate 
B) acetone 
C) 3-hydroxybutyrate 
D) All of these are used. 
E) None of these are used.

Question 13

The first step of the β-oxidation cycle,which is a dehydrogenation,requires what coenzyme?

Accepted Answer

A) ATP 
B) FAD 
C) NAD+ 
D) NADP+ 
A) ATP 
B) FAD 
C) NAD+ 
D) NADP+

Question 14

The hormones ________ and ________ control the release of energy from stored triacylglycerol.

Accepted Answer

A) insulin;cortisone 
B) adrenalin;glucagon 
C) norepinephrine;cortisone 
D) insulin;glucagon 
E) adrenalin;norepinephrine 
A) insulin;cortisone 
B) adrenalin;glucagon 
C) norepinephrine;cortisone 
D) insulin;glucagon 
E) adrenalin;norepinephrine

Question 15

How many CO2 molecules are released in the formation of a 16-carbon fatty acid by lipogenesis?

Accepted Answer

A) 8 
B) 9 
C) 7 
D) 6 
E) 5 
A) 8 
B) 9 
C) 7 
D) 6 
E) 5

Question 16

Match the following.
-beta oxidation

Accepted Answer

A) a condition which results from increased concentrations of ketone bodies in the blood 
B) the catabolic reaction in which fatty acids are broken down two carbons at a time 
C) presence of ketone bodies in the urine 
D) the anabolic process of synthesizing fatty acids 
A) a condition which results from increased concentrations of ketone bodies in the blood 
B) the catabolic reaction in which fatty acids are broken down two carbons at a time 
C) presence of ketone bodies in the urine 
D) the anabolic process of synthesizing fatty acids

Question 17

Which molecule is not associated with synthesis of triacylglycerides?

Accepted Answer

A) glycerol 3-phosphate 
B) NADH 
C) coenzyme A 
D) carnitine 
E) fatty acids 
A) glycerol 3-phosphate 
B) NADH 
C) coenzyme A 
D) carnitine 
E) fatty acids

Question 18

The synthesis of fatty acids takes place

Accepted Answer

A) by simply the reverse reactions of the fatty acid spiral. 
B) in the same location within a cell as the fatty acid spiral. 
C) by different reactions than the reverse of the fatty acid spiral and in a different cellular location. 
D) More than one response is correct. 
E) No response is correct. 
A) by simply the reverse reactions of the fatty acid spiral. 
B) in the same location within a cell as the fatty acid spiral. 
C) by different reactions than the reverse of the fatty acid spiral and in a different cellular location. 
D) More than one response is correct. 
E) No response is correct.

Question 19

Which lipoprotein carries triacylglycerols from the liver to peripheral tissues for storage?

Accepted Answer

A) HDL 
B) LDL 
C) VLDL 
D) IDL 
E) chylomicrons 
A) HDL 
B) LDL 
C) VLDL 
D) IDL 
E) chylomicrons

Question 20

Which statements are true for the process of lipogenesis?
I.It occurs in the mitochondria.
II.Acyl carrier proteins are involved.
III.NADPH is the coenzyme.
IV.The molecule increases in length by two carbons.
V.Energy is released in the process.

Accepted Answer

A) I,III,V 
B) II,IV 
C) I,III 
D) I,II,III,IV,V 
E) II,III,IV 
A) I,III,V 
B) II,IV 
C) I,III 
D) I,II,III,IV,V 
E) II,III,IV

Exam 24: Lipid Metabolism

The first chemical step in the breakdown of triacylglycerols is

If lipid catabolism produces more acetyl-CoA than the citric acid cycle can consume,but there is still a need for energy,the process of ________ takes over.

Chylomicrons are the least dense of all the lipoprotein/lipid combinations because

Which factor is the same in both lipogenesis and β-oxidation of fatty acids?

The molecule that is a precursor to the other ketone bodies is

Which is the correct term for the micelle-like structures which transport triglycerides in the bloodstream after digestion?

What is the role of a chylomicron?

High density lipoproteins contain a greater amount of ________ than do low density lipoproteins.

Where do the first chemical changes in the digestion of dietary fats take place?

Digestion of lipids begins in the ________,in a process catalyzed by ________.

Which molecule is associated with transport of fatty acids into the mitochondrial matrix?

Which of the ketone bodies is as an energy source for heart and muscle tissue during the early stages of starvation?

The first step of the β-oxidation cycle,which is a dehydrogenation,requires what coenzyme?

The hormones ________ and ________ control the release of energy from stored triacylglycerol.

How many CO2 molecules are released in the formation of a 16-carbon fatty acid by lipogenesis?

Match the following. -beta oxidation

Which molecule is not associated with synthesis of triacylglycerides?

The synthesis of fatty acids takes place

Which lipoprotein carries triacylglycerols from the liver to peripheral tissues for storage?

Which statements are true for the process of lipogenesis? I.It occurs in the mitochondria. II.Acyl carrier proteins are involved. III.NADPH is the coenzyme. IV.The molecule increases in length by two carbons. V.Energy is released in the process.

Matter and Measurements

Atoms and the Periodic Table

Ionic Compounds

Molecular Compounds

Classification and Balancing of Chemical Reactions

Chemical Reactions: Mole and Mass Relationships

Chemical Reactions: Energy, rates, and Equilibrium

Gases, liquids, and Solids

Solutions

Acids and Bases

Nuclear Chemistry

Introduction to Organic Chemistry: Alkanes

Alkenes, alkynes, and Aromatic Compounds

Some Compounds With Oxygen, sulfur, or a Halogen

Aldehydes and Ketones

Amines

Carboxylic Acids and Their Derivatives

Amino Acids and Proteins

Enzymes and Vitamins

Carbohydrates

The Generation of Biochemical Energy

Carbohydrate Metabolism

Lipids

Protein and Amino Acid Metabolism

Nucleic Acids and Protein Synthesis

Genomics

Chemical Messengers: Hormones, neurotransmitters, and Drugs

Body Fluids

Filters

Digestion of lipids begins in the ,in a process catalyzed by .

The hormones and control the release of energy from stored triacylglycerol.

How many CO₂ molecules are released in the formation of a 16-carbon fatty acid by lipogenesis?