Question 1

Which of the following does not occur when progesterone is synthesized from cholesterol?

Accepted Answer

A)  the oxidation of an alcohol 
B)  the shortening of the aliphatic side chain 
C)  the removal of a methyl group 
D)  the hydroxylation of an aliphatic chain 
A)  the oxidation of an alcohol 
B)  the shortening of the aliphatic side chain 
C)  the removal of a methyl group 
D)  the hydroxylation of an aliphatic chain

Question 2

How are the hydrophilic heads and hydrophobic tails of complex lipids distributed in the lipid bilayer?

Accepted Answer

A)  The hydrophilic heads project to the cytoplasm, and the hydrophobic tails project to the exterior of the cell. 
B)  The hydrophilic heads project to the exterior of the cell, and the hydrophobic tails project to the cytoplasm. 
C)  Both the hydrophilic heads and the hydrophobic tails are nonuniformly arranged across the bilayer. 
D)  Some membranes have only hydrophilic heads, whereas other membranes have only hydrophobic tails. 
A)  The hydrophilic heads project to the cytoplasm, and the hydrophobic tails project to the exterior of the cell. 
B)  The hydrophilic heads project to the exterior of the cell, and the hydrophobic tails project to the cytoplasm. 
C)  Both the hydrophilic heads and the hydrophobic tails are nonuniformly arranged across the bilayer. 
D)  Some membranes have only hydrophilic heads, whereas other membranes have only hydrophobic tails.

Question 3

Which mechanism is involved in the transport of nonpolar molecules through a membrane?

Accepted Answer

A)  active transport 
B)  diffusion 
C)  osmosis 
D)  all of these 
A)  active transport 
B)  diffusion 
C)  osmosis 
D)  all of these

Question 4

Which of the following linkages can be found in sphingolipids?

Accepted Answer

A)  sphingosine−serine−phosphate 
B)  sphingosine−phosphate−choline 
C)  phosphate−sphingomyelin−choline 
D)  none of these 
A)  sphingosine−serine−phosphate 
B)  sphingosine−phosphate−choline 
C)  phosphate−sphingomyelin−choline 
D)  none of these

Question 5

To which class of inhibitors does RU486 belong?

Accepted Answer

A)  cooperative inhibitor 
B)  competitive inhibitor 
C)  noncompetitive inhibitor 
D)  selective inhibitor 
A)  cooperative inhibitor 
B)  competitive inhibitor 
C)  noncompetitive inhibitor 
D)  selective inhibitor

Question 6

Identify a polyunsaturated fatty acid.

Accepted Answer

A)  arachidonic acid 
B)  palmitoleic acid 
C)  stearic acid 
D)  oleic acid 
A)  arachidonic acid 
B)  palmitoleic acid 
C)  stearic acid 
D)  oleic acid

Question 7

In sphingomyelin, which type of bond exists between the -NH2 group of sphingosine and a fatty acid?

Accepted Answer

A)  an amide bond 
B)  an azide bond 
C)  a hydrogen bond 
D)  an anhydride bond 
A)  an amide bond 
B)  an azide bond 
C)  a hydrogen bond 
D)  an anhydride bond

Question 8

Examine the following triglyceride.   To which carbon of the glycerol molecule is stearic acid bound?

Accepted Answer

A)  top 
B)  central 
C)  bottom 
D)  Stearic acid is not present in this structure. 
A)  top 
B)  central 
C)  bottom 
D)  Stearic acid is not present in this structure.

Question 9

Which of the following is a function of lipids?

Accepted Answer

A)  They store energy within cells. 
B)  They serve as chemical messengers. 
C)  They serve as components of cell membranes. 
D)  All of these are functions of lipids. 
A)  They store energy within cells. 
B)  They serve as chemical messengers. 
C)  They serve as components of cell membranes. 
D)  All of these are functions of lipids.

Question 10

Which of the following is a triple-bond derivative of testosterone?

Accepted Answer

A)  norethindrone 
B)  norethynodrel 
C)  ethynodiol diacetate 
D)  all of these 
A)  norethindrone 
B)  norethynodrel 
C)  ethynodiol diacetate 
D)  all of these

Question 11

Which of the following is a physiological effect of anti-inflammatory drugs such as Vioxx and Celebrex?

Accepted Answer

A)  the enhanced production of lipids that form an atherosclerotic plaque 
B)  the inhibition of COX-1 activity 
C)  the inhibition of ulcer formation 
D)  none of these 
A)  the enhanced production of lipids that form an atherosclerotic plaque 
B)  the inhibition of COX-1 activity 
C)  the inhibition of ulcer formation 
D)  none of these

Question 12

Examine the following ball-and-stick model. Atoms other than carbon and hydrogen are labeled with the name of the element.   At what position does ketone form when this compound is converted to progesterone?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  In this conversion, a ketone is not formed. 
A)  1 
B)  2 
C)  3 
D)  4 
E)  In this conversion, a ketone is not formed.

Question 13

Which of the following lipoproteins are commonly called "good cholesterol"?

Accepted Answer

A)  chylomicrons 
B)  HDLs 
C)  LDLs 
D)  VLDLs 
A)  chylomicrons 
B)  HDLs 
C)  LDLs 
D)  VLDLs

Question 14

What is the minimum number of double bonds that must be present in a polyunsaturated fatty acid?

Accepted Answer

A)  2 
B)  3 
C)  4 
D)  5 
A)  2 
B)  3 
C)  4 
D)  5

Question 15

Which of the following reactions is the source of trans fatty acids found in certain processed foods?

Accepted Answer

A)  condensation 
B)  dehydration 
C)  hydrogenation 
D)  hydrolysis 
A)  condensation 
B)  dehydration 
C)  hydrogenation 
D)  hydrolysis

Question 16

Which of the following happens because of increased aldosterone secretion in the kidneys?

Accepted Answer

A)  the reabsorption of Na+ and Cl− in the kidney 
B)  the reabsorption of Na+ in the kidney and the loss of Cl− from the kidney 
C)  the loss of Na+ and Cl− from the kidney 
D)  the loss of Na+ from the kidney and the reabsorption of Cl− in the kidney 
A)  the reabsorption of Na+ and Cl− in the kidney 
B)  the reabsorption of Na+ in the kidney and the loss of Cl− from the kidney 
C)  the loss of Na+ and Cl− from the kidney 
D)  the loss of Na+ from the kidney and the reabsorption of Cl− in the kidney

Question 17

Examine the following ball-and-stick model. Atoms other than carbon and hydrogen are labeled with the name of the element.   Which of the following statements correctly characterizes this substance?

Accepted Answer

A)  It is a complex lipid. 
B)  It is a precursor of peptide hormones. 
C)  It is soluble in water. 
D)  It is present in cell membranes. 
E)  None of these statements are correct. 
A)  It is a complex lipid. 
B)  It is a precursor of peptide hormones. 
C)  It is soluble in water. 
D)  It is present in cell membranes. 
E)  None of these statements are correct.

Question 18

How does aspirin block the active site of cyclooxygenase enzymes?

Accepted Answer

A)  by adding an acetyl group to the enzyme's active site 
B)  by adding a methyl group to the enzyme's active site 
C)  by removing an anhydride group from the enzyme's active site 
D)  by removing a carbonyl group from the enzyme's active site 
A)  by adding an acetyl group to the enzyme's active site 
B)  by adding a methyl group to the enzyme's active site 
C)  by removing an anhydride group from the enzyme's active site 
D)  by removing a carbonyl group from the enzyme's active site

Question 19

Lecithin is a major component of egg yolk. What is the role of lecithin in egg yolk?

Accepted Answer

A)  It increases the protein content of yolk. 
B)  It acts as a natural emulsifying agent. 
C)  It decreases the trans fat content of yolk. 
D)  It acts as an excellent antioxidant. 
A)  It increases the protein content of yolk. 
B)  It acts as a natural emulsifying agent. 
C)  It decreases the trans fat content of yolk. 
D)  It acts as an excellent antioxidant.

Question 20

Which of the following alcohols can be found in glycerophospholipids?

Accepted Answer

A)  choline 
B)  serine 
C)  inositol 
D)  all of these 
A)  choline 
B)  serine 
C)  inositol 
D)  all of these

Exam 20: Lipids

Which of the following does not occur when progesterone is synthesized from cholesterol?

How are the hydrophilic heads and hydrophobic tails of complex lipids distributed in the lipid bilayer?

Which mechanism is involved in the transport of nonpolar molecules through a membrane?

Which of the following linkages can be found in sphingolipids?

To which class of inhibitors does RU486 belong?

Identify a polyunsaturated fatty acid.

In sphingomyelin, which type of bond exists between the -NH2 group of sphingosine and a fatty acid?

Examine the following triglyceride. To which carbon of the glycerol molecule is stearic acid bound?

Which of the following is a function of lipids?

Which of the following is a triple-bond derivative of testosterone?

Which of the following is a physiological effect of anti-inflammatory drugs such as Vioxx and Celebrex?

Examine the following ball-and-stick model. Atoms other than carbon and hydrogen are labeled with the name of the element. At what position does ketone form when this compound is converted to progesterone?

Which of the following lipoproteins are commonly called "good cholesterol"?

What is the minimum number of double bonds that must be present in a polyunsaturated fatty acid?

Which of the following reactions is the source of trans fatty acids found in certain processed foods?

Which of the following happens because of increased aldosterone secretion in the kidneys?

Examine the following ball-and-stick model. Atoms other than carbon and hydrogen are labeled with the name of the element. Which of the following statements correctly characterizes this substance?

How does aspirin block the active site of cyclooxygenase enzymes?

Lecithin is a major component of egg yolk. What is the role of lecithin in egg yolk?

Which of the following alcohols can be found in glycerophospholipids?

Matter, Energy, and Measurement

Atoms

Chemical Bonds

Chemical Reactions

Gases, Liquids, and Solids

Solutions and Colloids

Reaction Rates and Chemical Equilibrium

Acids and Bases

Nuclear Chemistry

Organic Chemistry

Alkanes

Alkenes, Alkynes, and Aromatic Compounds

Alcohols, Ethers, and Thiols

Chirality: the Handedness of Molecules

Amines

Aldehydes and Ketones

Carboxylic Acids

Carboxylic Anhydrides, Esters, and Amides

Carbohydrates

Proteins

Enzymes

Chemical Communications: Neurotransmitters and Hormones

Nucleotides, Nucleic Acids, and Heredity

Gene Expression and Protein Synthesis

Bioenergetics: How the Body Converts Food to Energy

Specific Catabolic Pathways: Carbohydrate, Lipid, and Protein Metabolism

Biosynthetic Pathways

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Body Fluids

Filters

In sphingomyelin, which type of bond exists between the -NH₂ group of sphingosine and a fatty acid?