Lipids Chapter 23 Test Bank Answers

Package Title: Solomons Test Bank

Course Title: Solomons 12e

Chapter Number: 23

Question type: Multiple choice

1) What of the following will fill properly the blanks in the sentence.

Lipids are classified according to ___, and they include ___ structural types.

a) their structure; two

b) their melting temperature; fats and oils.

c) their melting point; triglycerides and phospholipids.

d) the physical operation done to isolate them; a variety of

e) their structure; only terpene and steroid.

Topic: General Lipid Types and Information

Section: 23.1

Difficulty Level: Easy

2) What of the following solvents would dissolve triacylglycerols?

a) Water and chloroform

b) Acetic acid and water

c) Chloroform and diethyl ether

d) Aqueous NaOH and acetic acid

e) They are soluble in water only

Topic: General Lipid Types and Information

Section: 23.1

Difficulty Level: Medium

3) What is a mixed triacylglycerol?

a) It is a lipid where a terpene is esterifying glycerol

b) It is a triester of glycerol where the acyl groups are identical

c) It is a triester formed by glycerol and acetic acid

d) It is a triester of glycerol where the fatty acids are not all identical

e) It is an ester between glycerol and cholesterol

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

4) A simple triacylglycerol is one that:

a) Upon hydrolysis produces glycerol and three different fatty acids.

b) Upon hydrolysis produces glycerol and at least two different fatty acids.

c) Upon saponification gives glycerol and three fatty acid salts.

d) Upon saponification gives three esters.

e) Upon hydrolysis produces glycerol and three mol of a fatty acid.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

5) What is likely to be a natural fatty acid?

I)

II)

III)

IV)

V)

a) Compounds I and IV

b) Only compound III

c) Compounds II and III

d) Compounds IV and V

e) Only compound II

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

6) Which of the following statements regarding triacylglycerols is not true?

a) They are synthesized in the body by adipocytes.

b) They have an odd number of carbon atoms.

c) They are solid if they do not have alkene groups.

d) Those which can be hydrogenated undergo a significant change in melting point upon hydrogenation.

e) They can be hydrolyzed to give glycerol and fatty acids.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

7) Which of the following statements regarding triacylglycerols is not true?

a) Some undergo autoxidation with oxygen from air.

b) They are solid if they do not have alkene groups.

c) They form lipid bilayers.

d) They form micelles in water.

e) Two of these choices are false statements.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

8) Which is an untrue statement concerning the fatty acid moieties of naturally occurring triacylglycerols?

a) Generally, they possess an even number of carbon atoms.

b) Most have unbranched carbon chains.

c) The double bonds, when present, all are in the cis configuration.

d) Where two or three double bonds are present in the same fatty acid moiety, they comprise a conjugated system.

e) The fatty acid moieties in a particular triacylglycerol usually are different.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

9) Which is not a correct statement concerning naturally occurring triacylglycerols?

a) The greater the degree of unsaturation, the higher the melting point.

b) Saponification yields glycerol and a mixture of carboxylic acid salts.

c) Solid triacylglycerols are termed "fats."

d) Regardless of the exact nature of the R groups, such compounds are water-insoluble.

e) Such compounds frequently are called "triglycerides."

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

10) Of the saturated fatty acids found in fats and oils, this one normally is the most abundant:

a) Capric acid

b) Lauric acid

c) Myristic acid

d) Palmitic acid

e) Stearic acid

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

11) Consider a micelle composed of the phosphatidyl choline, shown below. Which part(s) of the molecule would form the hydrophilic surface of the micelle?

a) 1 and 2

b) 2

c) 2 and 3

d) 1

e) 3

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

12) Which of these is a detergent?

a) CH₃(CH₂)₁₆COO^–Na⁺

b) [CH₃(CH₂)₁₄COO^–]₂Ca²⁺

c) CH₃(CH₂)₁₀CH₂SO₃^–Na⁺

d) HOCH₂CHOHCH₂OH

e) CH₃(CH₂)₁₄CH₂SH

Topic: Soaps, Detergents, and Micelles

Section: 23.2

Difficulty Level: Easy

13) What is an undesired effect of the partial hydrogenation of oils?

a) The oil gets very liquidly

b) The oil gets transformed into a brittle solid

c) The oil gets solid but the remaining double bonds are all in cis stereochemistry

d) Some double bonds are isomerized to trans stereochemistry

e) All the double bonds are hydrogenated and the fatty acids become fully saturated

Topic: Hydrogenation

Section: 23.2

Difficulty Level: Easy

14) What of the following structures is a biodegradable soap or detergent?

a) I, III and IV

b) Only I

c) II and III

d) III and IV

e) I and III

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

15) Which of the following would serve as the basis for a simple chemical test that would distinguish between stearic acid and oleic acid?

a) NaOH/H₂O

b) NaHCO₃/H₂O

c) HCl/H₂O

d) Ag(NH₃)₂⁺

e) Br₂/CCl₄

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

16) Which of the following would not be helpful in distinguishing between oleic acid, linoleic acid and linolenic acid?

a) Examine the stoichiometry of the reaction with Br₂, CCl₄

b) Examine the stoichiometry of complete catalytic hydrogenation.

c) Examine the products obtained after subjecting the sample to catalytic hydrogenation

d) Examine products obtained after subjecting the sample to: i) O₃, CH₂Cl₂; ii) Zn, CH₃CO₂H

e) Examine the molecular weight of the acids.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

17) Which of the following might be helpful in distinguishing between oleic acid and linoleic acid?

a) Examine the stoichiometry of the reaction with NaOH/H₂O

b) Examine the stoichiometry of complete catalytic hydrogenation.

c) Examine products obtained after subjecting the sample to catalytic hydrogenation

d) Examine products obtained after subjecting the sample to: i) O₃, CH₂Cl₂; ii) Zn, CH₃CO₂H

e) Two of these choices.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

18) Which fatty acid is not likely to occur commonly in natural sources?

a) CH₃(CH₂)₁₂COOH

b) CH₃(CH₂)₁₄COOH

c)

d)

e)

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

19) Which fatty acid is not likely to occur commonly in natural sources?

a) Tetradecanoic acid

b) Pentadecanoic acid

c) Hexadecanoic acid

d) (9Z,12Z)-octadeca-9,12-dienoic acid

e) (Z)-hexadeca-9-enoic acid

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

20) Which fatty acid is not likely to occur commonly in natural sources?

a) (Z)-11-Tetradecenoic acid

b) (Z)-9-Hexadecenoic acid

c) Hexadecanoic acid

d) (9Z,12Z)-9,12-octadecadienoic acid

e) (Z)-9-pentadecenoic acid

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

21) Which fatty acid is likely to occur commonly in natural sources?

a) II

b) I and IV

c) II and III

d) II, III and IV

e) V

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

22) Which of the following could be used to prepare myristic acid, CH₃(CH₂)₁₂COOH?

a) CH₃(CH₂)₁₁CH₂Br, CN^–, heat; then H₃O⁺, heat

b) CH₃(CH₂)₁₁CH₂Br, Mg, (C₂H₅)₂O; then CO₂; then H₃O⁺

c) CH₃(CH₂)₁₂CHO, Ag₂O, OH^–; then H₃O⁺

d) Two of these choices.

e) All of these choices.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

23) Which of the following could be used to prepare myristic acid, CH₃(CH₂)₁₂COOH?

a) CH₃(CH₂)₁₁CH₂Br, CN^–, heat; then H₃O⁺, heat

b) CH₃(CH₂)₁₁CH₂Br, Mg, (C₂H₅)₂O; then CO₂; then H₃O⁺

c) CH₃(CH₂)₁₃CHO, Ag₂O, OH^–; then H₃O⁺

d) Two of these choices.

e) All of these choices.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

24) Which of the following could be used to prepare stearic acid, CH₃(CH₂)₁₆COOH?

a) CH₃(CH₂)₁₅CH₂Br, CN^–, heat; then H₃O⁺, heat

b) CH₃(CH₂)₁₅CH₂Br, Mg, (C₂H₅)₂O; then HCHO; then H₃O⁺

c) CH₃(CH₂)₁₆CH₂Br, NaOH; then KMnO₄,OH^–, H₂O; then H₃O⁺

d) CH₃(CH₂)₁₅CH₂Br, CN^–, heat; then H₃O⁺, heat and CH₃(CH₂)₁₅CH₂Br, Mg, (C₂H₅)₂O; then HCHO; then H₃O⁺

e) CH₃(CH₂)₁₅CH₂Br, CN^–, heat; then H₃O⁺, heat and CH₃(CH₂)₁₆CH₂Br, NaOH; then KMnO₄,OH^–, H₂O; then H₃O⁺

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

25) How could you synthesize stearolic acid, CH₃(CH₂)₇CC(CH₂)₇COOH from oleic acid, CH₃(CH₂)₇CH=CH(CH₂)₇COOH?

a) Br₂, CCl₄; then 3 NaNH₂, heat; then H₃O⁺

b) Li, liq. NH₃; then H₃O⁺

c) H₂, Pd

d) Peracid; then H₃O⁺; then HA, H₂O, heat

e) Excess HCl; then KOH, C₂H₅OH, heat

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

26) Which of these reagents would not react with oleic acid?

a) H₂, Ni

b) PBr₃

c) CH₃MgI

d) NH₃/H₂O

e) NaBH₄

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

27) Which of these reagents would not react with oleic acid?

a) H₂, Ni

b) DIBAL-H (diisobutylaluminium hydride)

c) O₃/CH₂Cl₂

d) NH₃/H₂O

e) LAH (lithium aluminium hydride)

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

28) The ozonolysis of a fatty acid produces these fragments:

What is the identity of the fatty acid?

a) Stearic acid

b) Palmitoleic acid

c) Oleic acid

d) Linoleic acid

e) Linolenic acid

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

29) How many isomers, including stereoisomers, exist for the triacylglycerol which, on saponification, gives glycerol, 2 molar equivalents of palmitate and 1 molar equivalent of stearate?

a) 1

b) 2

c) 3

d) 4

e) 6

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

30) The final product of the following reaction sequence would be:

a) V

b) IV

c) I

d) II

e) III

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

31) What would be the product of the following reaction sequence?

a) CH₃(CH₂)₅CH=CH(CH₂)₁₄CH₃

b) CH₃(CH₂)₅COOCH₂(CH₂)₁₄CH₃ and CH₃(CH₂)₅CH=CH(CH₂)₇COOCH₂(CH₂)₁₄CH₃

c) CH₃(CH₂)₁₄COOCH₂(CH₂)₁₄CH₃

d) CH₃(CH₂)₁₃CHClCOOCH₂(CH₂)₁₄CH₃

e) CH₃(CH₂)₅CH=CH(CH₂)₇COOCH₂(CH₂)₁₄CH₃

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

32) The product of the following reaction sequence may be described as?

a) Alkoxyalkane

b) Alkyl alkanoate

c) Alkyl alkenoate

d) Acyl glycerol

e) Acyl Alkane

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

33) Which fatty acid is responsible for the putrid odor of rancid butter?

a) Valeric acid

b) Myristic acid

c) Stearic acid

d) Oleic acid

e) Butyric acid

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

34) The product of the following reaction sequence is nervonic acid. What is the structure of nervonic acid?

a)

b)

c)

d)

e)

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Hard

35) What would be the product, X, of the following reaction sequence?

a)

b)

c) CH₃(CH₂)₁₁CH₂NH₂

d) CH₃(CH₂)₁₂CONH₂

e) CH₃(CH₂)₁₂COBr

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Hard

36) In the vulcanization of rubber,

a) natural rubber is heated with sulfur.

b) reaction occurs at allylic positions.

c) cross-linking results in a hardening of the rubber.

d) disulfide bridges are formed.

e) All of these choices.

Topic: Rubber

Section: 23.3

Difficulty Level: Easy

37) Essential oils are constituted by

a) fatty acids and glycerol

b) triacylglycerol

c) terpenes only

d) glycerol

e) terpenoids and terpenes

Topic: Essential Oils

Section: 23.3

Difficulty Level: Easy

38) Which compound is a sesquiterpene?

a) I

b) II

c) III

d) IV

e) V

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

39) Which structure represents a terpene likely to be found in nature?

a) II

b) I

c) IV

d) III

e) V

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

40) To which class of terpenes does the terpene shown below, bisabolene, belong?

a) Monoterpenes

b) Sesquiterpenes

c) Diterpenes

d) Triterpenes

e) Tetraterpenes

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

41) How many isoprene units are in vitamin A?

a) 1

b) 2

c) 3

d) 4

e) More than 4

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

42) Which compound below does not obey the isoprene rule?

a) V

b) II

c) IV

d) I

e) III

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

43) Which of the following compounds would be most likely to be found in nature? (Hint: recall the isoprene rule.)

a) I

b) II

c) IV

d) III

e) V

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

44) Which is the proper representation of three successive isoprene units in natural rubber?

a) I

b) II

c) III

d) IV

e) V

Topic: Rubber

Section: 23.3

Difficulty Level: Medium

45) A sample is know to be either  or -pinene. What chemical method would you use to determine which one is the sample?

a) Oxidation with CrO₃, -pinene will produce formaldehyde

b) Ozonolysis; -pinene will show a monocyclic product, not present for -pinene.

c) Addition of Br₂ to the double bond. Observe disappearance of the color.

d) Acid hydrolysis would generate different products for each of the pinene.

e) Hydrogenation would give different products for each of the pinene.

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

49) In -carotene, how many tail-to-tail links of isoprene units are there?

a) 1

b) 2

c) 3

d) 4

e) More than 4

Topic: Terpenes

Section: 23.3

Difficulty Level: Hard

46) Which reagent might be used to convert 5-cholest-1-en-3-ol into 5-cholestan-3-ol?

a) CrO₃/pyridine

b) KMnO₄/H₂O

c) CH₃MgI

d) H₂/Pt

e) Li/C₂H₅NH₂

Topic: Steroids

Section: 23.4

Difficulty Level: Easy

47) Which of the following is a female sex hormone?

a) Ergosterol

b) Estradiol

c) Cortisone

d) Androsterone

e) Cholic acid

Topic: Steroids

Section: 23.4

Difficulty Level: Easy

48) The synthesis of cortisone required placing a ketone function at the 11-position of a steroid. Where is position 11?

a) I

b) II

c) III

d) IV

e) V

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

49) Which is an untrue statement concerning cholesterol?

a) Cholesterol decolorizes a solution of Br₂ in CCl₄.

b) Cholesterol reacts with 2,4-dinitrophenylhydrazine.

c) Cholesterol is optically active.

d) Cholesterol is water-insoluble.

e) Cholesterol reacts with H₂/Pd

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

50) The reaction of cholesterol with dilute aqueous KMnO₄ at 0–5 °C produces which of these compounds (A and B rings only shown)?

a) I

b) II

c) III

d) IV

e) V

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

51) In the biosynthesis of vitamin D₂, which alkane bond of ergosterol is cleaved?

a) I

b) II

c) III

d) IV

e) V

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

52) Which of these is a correct systematic name for progesterone?

a) 2-Estrene-4,20-dione

b) 5-Androstene-4,19-dione

c) 4-Pregnene-3,20-dione

d) 5-Cholestene-5,19-dione

e) 4-Cholene-3,20-dione

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

53) What product would you expect when progesterone is treated with one molar equivalent of hydrogen in the presence of a platinum catalyst?

a) 5-Pregnane-3,20-dione

b) 5-Pregnane-3,20-dione

c) 5-Estrane-3,20-dione

d) 5-Estrane-3,20-dione

e) 5-Androstane-3,20-dione

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

54) Which is the correct systematic name for the steroid shown below?

a) 5-Androstan-3-ol

b) 5-Androstan-3-ol

c) 5-Androstan-3-ol

d) 5-Androstan-3-ol

e) 5-Estan-3-ol

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

55) How many stereogenic centers are there in cholesterol?

a) 2

b) 4

c) 6

d) 8

e) 16

Topic: Steroids

Section: 23.4

Difficulty Level: Hard

56) Estrone can be separated from testosterone by

a) Treatment of the mixture with aqueous NaOH and extraction with ethyl ether. Estrone is extracted in the ether phase.

b) Treatment of the mixture with NaOH and extraction with ethyl ether. Testosterone is extracted in the ether phase.

c) Treatment of the mixture with NaOH and extraction with ethyl ether. Estrone and testosterone are extracted in the ether phase.

d) Treatment of the mixture with NaHCO₃ and extraction with ethyl ether. Testosterone is extracted in the ether phase.

e) Treatment of the mixture with NaHCO₃ and extraction with ethyl ether. Estrone is extracted in the ether phase.

Topic: Steroids

Section: 23.4

Difficulty Level: Hard

57) Shown below is the formula for the antiinflammatory drug called prednisone. What is a correct systematic name for prednisone?

a) 17,21-Dihydroxypregna-1,4-diene-3,11,20-trione

b) 17,21-Dihydroxypregna-1,4-diene-3,11,20-trione

c) 17,19-Dihydroxypregna-1,4-diene-3,11,20-trione

d) 17,19-Dihydroxypregna-1,4-diene-3,11,20-trione

e) 17,21-Dihydroandrostan-1,4-diene-3,11,20-trione

Topic: Steroids

Section: 23.4

Difficulty Level: Hard

58) Which of the following characteristics are found in the class of C₂₀ carboxylic acids called prostaglandins?

a) A five membered ring

b) One or more double bonds

c) Several oxygen containing groups

d) Two of the above

e) All of these choices

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Easy

59) Some prostaglandins induce inflammation. Aspirin is an anti-inflammatory drug because:

a) Apparently it acetylates the enzyme cyclooxygenase.

b) It reacts with arachidonic acid preventing the synthesis of inflammatory prostaglandins.

c) It blocks the synthesis of the catalytic enzyme leading to inflammatory prostaglandins.

d) It reacts with inflammatory prostaglandins preventing them for being active.

e) It renders the arachidonic acid inactive in the synthesis of prostaglandins.

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Medium

60) What of the following is a (are) correct structure(s) for prostaglandin(s)?

a) I and II

b) I, III and IV

c) III

d) II

e) I and IV

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Medium

61) Which of the following is a phosphatidic acid?

a) I

b) II

c) III

d) IV

e) V

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

62) Which type of lipid gives these products on saponification?

HOCH₂CHOHCH₂OH RCO₂¯ R'CO₂¯ PO₄³¯ HOCH₂CH₂NH₂

a) Fat

b) Wax

c) Lecithin

d) Cephalin

e) Plasmalogen

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

63) Which type of phosphatide has the structural unit:

a) Cephalins

b) Phosphatidyl serines

c) Plasmalogens

d) Lecithins

e) Both cephalins and plasmalogens

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

64) Which of these lipids yields choline upon hydrolysis?

a) A lecithin only

b) A sphingomyelin and a cerebroside

c) A cephalin and a lecithin

d) A cerebroside and a cephalin

e) A lecithin and a sphingomyelin

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

65) Choline cannot be found as a product of hydrolysis of any representative of this class of lipids.

a) Cerebrosides

b) Phosphatidylserine

c) Plasmalogens

d) Waxes

e) None of these choices yield choline upon hydrolysis

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

66) d-Galactose is an example of a class of compounds that can be formed during the hydrolysis of:

a) Sphingomyelins

b) Cerebrosides

c) Plasmalogens

d) Waxes

e) Both plasmalogens and waxes

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

67) Which of these lipids does not yield glycerol upon hydrolysis?

a) A lecithin

b) A sphingolipid

c) A cephalin

d) A triacylglycerol

e) A plasmalogen

Topic: General Lipid Types and Information

Section: 23.2 and 23.6

Difficulty Level: Medium

68) Which of these lipids yields glycerol upon hydrolysis?

a) A lecithin

b) A phosphatidylserine

c) A cephalin

d) A triacylglycerol

e) All of these choices.

Topic: General Lipid Types and Information

Section: 23.2 and 23.6

Difficulty Level: Medium

69) Which type of lipid gives these products on saponification?

HOCH₂CHOHCH₂OH RCO₂¯ RCH₂CHO PO₄³¯ HOCH₂CH₂NH₂

a) Fat

b) Wax

c) Lecithin

d) Cephalin

e) Plasmalogen

Topic: General Lipid Types and Information

Section: 23.7

Difficulty Level: Medium

70) Which of these is a wax?

a)

b)

c)

d)

e) CH₃(CH₂)₂₄CH₂OH

Topic: General Lipid Types and Information

Section: 23.7

Difficulty Level: Medium

71) Which of these is most likely to have properties resembling natural waxes?

a) I

b) II

c) III

d) IV

e) V

Topic: General Lipid Types and Information

Section: 23.7

Difficulty Level: Medium

72) One of the products of hydrolysis of a wax gave the following ¹H NMR spectrum, ppm (integral): 3.62(2); 1.58(2), 1.45(2); 1.27(50); 0.88(3). The molecular weight is 410.8 amu.

What is the compound?

a) CH₃(CH₂)₅CH₂OH

b) CH₃(CH₂)₂₅CH₂OH

c) CH₃(CH₂)₂₅CH₂CH₂OH

d) (CH₃)₂CH(CH₂)₂₄CH₂OH

e) CH₃(CH₂)₂₅ CH₂CO₂H

Topic: General Lipid Types and Information

Section: 23.7

Difficulty Level: Hard

73) Choline cannot be found as a product of hydrolysis of any representative of this class of lipids.

a) Sphingomyelins

b) Lecithins

c) Plasmalogens

d) Waxes

e) Both plasmalogens and waxes

Topic: General Lipid Types and Information

Section: 23.6 and 23.7

Difficulty Level: Medium

Question type: fill-in-the-blank

74) Unlike carbohydrates and proteins, which are defined in terms of their structures, lipids are defined in terms of ___.

Topic: Lipids

Section: 23.2

Difficulty Level: Easy

75) Saturated fatty acids pack efficiently. Therefore the corresponding triacylglycerols tend to be ___ at room temperature and are called ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

76) Unsaturated fatty acids have a bend in the carbon chain that interferes with packing. Therefore the corresponding triacylglycerols are generally ___ at room temperature and are called ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

77) The primary function of triacylglycerols (triglycerides) in animals is ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

78) Salts of long-chain fatty acids are known as ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

Question type: Essay

79) Explain how soap removes dirt from clothes.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

Question type: fill-in-the-blank

80) The characteristic odor of rancid butter is attributed to ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

81) In naturally occurring polyunsaturated fatty acids, the relative position of double bonds is rarely ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

82) There is growing evidence that “trans” fats are associated with an increased risk of ___, and the FDA now requires “trans fat” information to be provided on nutrition labels.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

83) In naturally occurring polyunsaturated fatty acids, the stereochemistry of the double bonds is rarely ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

84) Prolonged heating of naturally occurring polyunsaturated fats may cause the stereochemistry of the double bonds to change from ___.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

85) How would you convert oleic acid into these substances?

A) methyl oleate

B) methyl stearate

C) nonanal

D) 9-octadecynoic acid

E) 2-bromostearic acid

Topic: Fatty Acids and Triacylglycerols

Section: 23.2

Difficulty Level: Hard

86) Draw the structure for the product of the reaction presented on the scheme.

Topic: Fatty Acids and Triacylglycerols

Section: 23.2

Difficulty Level: Medium

87) Draw the structure for the product of the reaction presented on the scheme.

Topic: Fatty Acids and Triacylglycerols

Section: 23.2

Difficulty Level: Medium

88) Olestra, a synthetic fat substitute, contributes nothing to the caloric value of foods prepared with it, because it passes through the body without being digested. Why are the lipases, responsible for facilitating normal fat hydrolysis, unable to facilitate the hydrolysis of olestra?

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

89) How could you synthesize stearolic acid, CH₃(CH₂)₇C≡C(CH₂)₇COOH from oleic acid, CH₃(CH₂)₇CH=CH(CH₂)₇COOH? Specify stoichiometric details, providing a brief explanation of your rationale.

Oleic acid needs to be protected in the first step with methanol; the reaction is catalyzed with acid. Then bromine addition will generate a dibromine intermediate product that can be dehydrohalogenated using at least two equivalents of a strong base such as KOH. Finally, the methyl protecting group is cleaved with HCl.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

90) Suggest a reasonable synthetic strategy for the synthesis of N,N-dimethylstearamide, CH₃(CH₂)₁₆CON(CH₃)₂ from oleic acid, cis-9-octadecenoic acid

i) H₂, Ni; ii) PBr₃; iii) (CH₃)₂NH

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

91) One of the intermediates in a prostaglandin synthesis is shown below.

Which reaction might be employed to make this molecule from 1,1-dimethoxy-3-nitropropane and an appropriate -unsaturated aldehyde? Show the structural details of the reagents as well as any catalysts that might be needed.

Topic: Synthesis

Section: 23.2

Difficulty Level: Medium

92) Draw the structures of three soaps or detergents, in which the alkyl portion is CH₃(CH₂)₁₂ and the functional group is:

sodium carboxylate,

sodium alkanesulfonate and

sodium alkyl sulfate

Explain why these substances may be useful as “dirt removers.”

Each of these substances has a polar “head” and a non-polar “tail.” This allows them to form micelles when mixed with water. These micelle clusters are dispersed throughout the aqueous phase, with the polar heads on the outside and the non-polar ends on the inside of the spherical clusters. When these micelles come into contact with the non-polar, oily surface of “dirt,”the dirt gets attracted to the non-polar center of the micelle, where it is then “trapped.” Upon rinsing, the micelles, along with the trapped dirt, get washed away.

Topic: Soaps and Synthetic Detergents

Section: 23.2

Difficulty Level: Medium

93) Fats can be either optically active or inactive, depending on their structure. Draw the structure of an optically active fat that yields 2 equiv. of stearic acid and 1 equiv. of oleic acid on hydrolysis. Draw the structure of an optically inactive fat that yields the same products.

Topic: Fats

Section: 23.2

Difficulty Level: Medium

94) Draw the structure of the products you would expect to obtain from reaction of glyceryl trioleate with the following:

a) excess Br₂ in CCl₄ e) LiAlH₄, then H₃O⁺

b) H₂/Pd f) CH₃MgBr, then H₃O⁺

c) NaOH/H₂O

d) O₃, then Zn/CH₃COOH

Topic: Fats

Section: 23.2

Difficulty Level: Hard

95) Show all isoprene units in the following structures:

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

96) Draw the most stable chair conformation of dihydrocarvone.

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

97) Show the location of the isoprene units in these terpenes.

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

98) What products would be obtained from the ozonolysis of zingiberine, found in the oil of ginger?

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

99) Identify the bonds that link the isoprene units in -farnesene, shown below. How are these units linked: head to head, tail to head or tail to tail?

-farnesene

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

100) Indicate by asterisks the chiral centers present in each of three terpenes shown below:

Topic: Terpenes

Section: 23.3

Difficulty Level: Medium

101) Draw the most stable chair conformation of menthol and label each substituent as axial or equatorial.

All substituents are equatorial.

Topic: Terpenes

Section: 23.3

Difficulty Level: Hard

102) Suggest a mechanism by which ψ-ionone is transformed into β-ionone on treatment with acid.

Topic: Terpenes

Section: 23.3

Difficulty Level: Hard

103) Draw the structures of the following compounds and show the positions of the isoprene units:

a) farnesol

b) retinal

c) squalene

d) β-carotene

Topic: Terpenes

Section: 23.3

Difficulty Level: Hard

104) Draw the structures of these molecules:

a) glyceryl trimyristate

b) methyl oleate

c) α-pinene

d) dihydrocarvone

Topic: Structure

Section: 23.2 and 23.3

Difficulty Level: Medium

105) There are three major classes of sex hormones:

a. female sex hormones [or ____________]

b. male sex hormones [or ____________]

c. pregnancy hormones [or ______________]

Topic: Steroid Hormones

Section: 23.4

Difficulty Level: Easy

106) Show the products you would expect to obtain from reaction of cholic acid with these reagents:

a) C₂H₅OH, HCl

b) PCC, CH₂Cl₂

c) BH₃ in THF, then H₃O⁺

c) No reaction.

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

107) Draw the product(s) of the reactions:

a) cholesterol + Ac₂O c) cholesterol + CH₃COOOH

b) testosterone + LiAlH₄ d) androsterone + CrO₃

Topic: Steroids

Section: 23.4

Difficulty Level: Hard

108) What products would you expect from reaction of estradiol with these reagents?

a) NaH, then CH₃I c) Br₂, FeBr₃

b) CH₃COCl, pyridine d) PCC in CH₂Cl₂

Topic: Steroids

Section: 23.4

Difficulty Level: Hard

109) How many chiral centers does prostaglandin E2 have? Assign R,S configurations to these centers.

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Medium

110) Draw representative structures for:

a) a fat b) a prostaglandin c) a steroid d) a terpene

Topic: General

Section: 23.2, 23.3, 23.4 and 23.5

Difficulty Level: Hard

111) Sphingolipids, proteins, and polysaccharides make up ___, the protective coating around nerve fibers.

Topic: Fats and Oils

Section: 23.6

Difficulty Level: Easy

112) Myelin, the protective coating around nerve fibers, is made up of ___.

Topic: Fats and Oils

Section: 23.6

Difficulty Level: Easy

113) How do sphingolipids differ from phospholipids?

Topic: Fats and Oils

Section: 23.6

Difficulty Level: Easy

114) How are soaps and phosphatides similar in their interaction with water?

Topic: Fats and Oils

Section: 23.2 and 23.6

Difficulty Level: Medium

115) Most waxes, commonly found as protective coatings on skin, fur, hair, leaves, fruits, etc., are ___.

Topic: Fats and Oils

Section: 23.7

Difficulty Level: Easy

116) Explain why it is not possible to measure a melting point for oils.

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

117) Explain why oils are liquid at room temperature while fats are solid.

Topic: Fats and Oils

Section: 23.7

Difficulty Level: Medium

118) The ¹H NMR spectrum shown is for trimyristine. Draw the structure of trimyristine and assign the signals in the spectrum to the different types of protons. Chemical shifts in ppm and integral ratios (in parentheses) are: 5.26 (1H); 4.22 (2H); 2.30 (2H); 1.61 (2H); 1.26 (20H); 0.88 (3H).

Assign. Shift(ppm)

A 5.26

B + C 4.22

D 2.30

E 1.61

F 1.26

G 0.88

Topic: Fats and Oils

Section: 23.7

Difficulty Level: Hard

119) Which fatty acid is likely to occur commonly in natural sources?

a) Tetradecanoic acid

b) (Z)-hexadeca-9-enoic acid

c) Hexadecanoic acid

d) (9Z,12Z)-octadeca-9,12-dienoic acid

e) All choices are correct

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

120) Which fatty acid is likely to occur commonly in natural sources?

a) (Z)-11-Tetradecenoic acid

b) (Z)-9-Hexadecenoic acid

c) Hexadecanoic acid

d) (9Z,12Z)-9,12-octadecadienoic acid

e) All choices are correct

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

121) Which fatty acid is NOT likely to occur commonly in natural sources?

a) I, II, III, IV

b) I and IV

c) II and III

d) II, III and IV

e) V

Topic: Fats and Oils

Section: Section: 23.2

Difficulty Level: Medium

122) Which of the following is NOT correct structure(s) for prostaglandin(s)?

a) II and III

b) I, III and IV

c) III

d) II

e) I and IV

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Medium

123) Which of these lipids yields glycerol upon hydrolysis?

a) A lecithin

b) A plasmalogen

c) A cephalin

d) A triacylglycerol

e) All of these choices are correct

Topic: General Lipid Types and Information

Section: 23.2 and 23.6

Difficulty Level: Medium

124) Which of these lipids does NOT yield glycerol upon hydrolysis?

a) A lecithin

b) A phosphatidylserine

c) A cephalin

d) A triacylglycerol

e) A sphingolipid

Topic: General Lipid Types and Information

Section: 23.2 and 23.6

Difficulty Level: Medium

125) Which of these is a triacylglycerol?

a)

b)

c)

d)

e) CH₃(CH₂)₂₄CH₂OH

Topic: General Lipid Types and Information

Section: 23.7

Difficulty Level: Medium

126) What of the following statements are true:

a) Fatty acids are linear and contain an even number of carbons.

b) Triacylglycerols contain ether functionalities.

c) Triacylglycerols are formed by long chain alcohols and glycerol.

d) Triacylglycerols containing unsaturated fatty acids have high melting temperature.

e) Two of these statements are true.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

127) Which of the following statements regarding triacylglycerols is not true?

a) They undergo alkaline hydrolysis to yield soaps.

b) They are liquid if they have alkene groups.

c) They are solid if they do not have one or more alkene groups.

d) They are soluble in water.

e) Some can be hydrogenated.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

128) Which of the following statements regarding triacylglycerols is true?

a) They form micelles when mixed with water.

b) They are liquid if they are unsaturated.

c) They are solid if they have alkyne bonds.

d) They can be used to wash dirty dishes

e) They are soluble in water.

Topic: General Lipid Types and Information

Section: 23.2

Difficulty Level: Easy

129) How could you convert an unsaturated fatty acid into a saturated fatty acid?

a) KMnO₄, OH^–, heat

b) OH^–, H₂O, heat; then H₃O⁺

c) H₂, Ni, pressure

d) H₃O⁺, H₂O, heat

e) O₃; then Zn, HOAc

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Easy

130) Rank the following fatty acids according to increasing melting point.

I: CH₃(CH₂)₁₆CO₂H

II: CH₃(CH₂)₇CH=CH(CH₂)₇CO₂H (cis)

III: CH₃(CH₂)₇CH=CH(CH₂)₇CO₂H (trans)

IV: HO₂C(CH₂)₇CH=CHCH₂CH=CH(CH₂)₇CH₃ (cis, cis)

a) I < II < III < IV

b) IV < III < II < I

c) II < IV < III < I

d) IV < II < III < I

e) IV < I < III < II

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

131) What of the following salts are useful for washing fatty stains in hard water?

a) II and V

b) I, II and V

c) I, III and IV

d) I, II, III, and IV

e) I, II, III, IV and V

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

132) Which of these reagents would not react with stearic acid?

a) H₂, Ni

b) SOCl₂

c) CH₃MgI

d) NH₃/H₂O

e) LAH (lithium aluminum hydride)

Topic: Fats and Oils

Section: 23.2

Difficulty Level: Medium

133) Which of the following statements regarding lipids is not true?

a) Lipids are soluble in non-polar organic solvents.

b) All lipids have the same functional groups.

c) Lipids include waxes, steroids, and triacylglycerols.

d) Lipids have little in common except their solubility.

e) Many lipids have biological roles.

Topic: General Lipid Types and Information

Section: 23.1 and 23.2

Difficulty Level: Easy

134) Which is the repeating unit of natural rubber?

a) I

b) II

c) III

d) IV

e) V

Topic: Rubber

Section: 23.3

Difficulty Level: Medium

135) Which of these is a male sex hormone?

a) Estrone

b) Cholic acid

c) Testosterone

d) Cortisone

e) Estradiol

Topic: Steroids

Section: 23.4

Difficulty Level: Easy

136) Which reagent might serve as the basis for a simple chemical test that would distinguish between 5-cholest-1-en-3-one and 5-cholestan-3-one?

a) Ag(NH₃)₂⁺

b) CrO₃/H₂SO₄

c) Br₂/CCl₄

d) NaOH/H₂O

e) C₆H₅NHNH₂

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

137) What product would be obtained by catalytic hydrogenation of 5-cholesten-3-ol?

a) 5-Cholestan-3-ol

b) 5-Cholestan-3-ol

c) 5-Cholestan-3-ol

d) 5-Cholestan-3-ol

e) 5-Cholesten-3,6-diol

Topic: Steroids

Section: 23.4

Difficulty Level: Medium

138) The biosynthesis of one series of prostaglandins begins with which of these fatty acids?

a) Palmitic acid

b) Stearic acid

c) Oleic acid

d) Linoleic acid

e) Arachidonic acid

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Easy

139) The compounds I and II are:

a) Prostaglandins.

b) Terpenoids.

c) I is a prostaglandin; II is not a prostaglandin.

d) I is an E type prostaglandin; II is an F type prostaglandin.

e) Both are fatty acids.

Topic: Prostaglandins

Section: 23.5

Difficulty Level: Medium

140) Which type of lipid gives the following products on saponification?

HOCH₂CHOHCH₂OH RCO₂¯ R'CO₂¯ PO₄³¯ [HOCH₂CH₂N(CH₃)₃]⁺OH^–

a) Fat

b) Wax

c) Lecithin

d) Cephalin

e) Plasmalogen

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

141) Which type of phosphatide contains the structural unit shown below?

a) Cephalins

b) Phosphatidyl serines

c) Plasmalogens

d) Lecithins

e) Both plasmalogens and lecithins

Topic: General Lipid Types and Information

Section: 23.6

Difficulty Level: Medium

142) A compound “Z” (C₁₀H₁₆), has _max at 184 nm in its UV spectrum. Catalytic hydrogenation of Z affords a mixture of diastereomers, which upon separation are identified to be cis-1-isopropyl-4-methylcyclohexane and trans-1-isopropyl-4-methylcyclohexane. Upon ozonolysis, Z yields formaldehyde and 3-acetyl-6-oxoheptanal. Suggest a structure for Z that is consistent with all of the above data, clearly explaining your rationale.

- IHD for Z: (C₁₀H₂₂ - C₁₀H₁₆)/2 = 3

- Hydrogenation affords 1-isopropyl-4-methylcyclohexane: so, Z must have the

same carbon skeleton, along with 2 pi bonds, i.e., 1 ring and 2  bonds (so that

IHD =3)

- Examination of the above carbon skeleton suggests that the pi bonds cannot

constitute an alkyne, so that the pi bonds must be present as 2 double bonds.

- _max at 184 nm in its UV spectrum suggests that these  bonds are not

conjugated.

- The stereochemistry of the hydrogenation products suggests that there must be a

bond at C-4 and a chiral center at C-1: hydrogenation eliminates the

asymmetry (and therefore chirality) at C-4. Hydrogenation from both faces of

the  bond at C-4 would lead to cis- and trans- orientation of the methyl and

isopropyl groups on the cyclohexane ring.

- The ozonolysis products suggest the position of the 2 double bonds: since there

are only 2 products, one bond must be within the ring, the other outside the ring.

Topic: Analysis and Structure Elucidation

Section: 23.2

Difficulty Level: Hard

143) Terpenes are built up from two or more five-carbon units known as ___.

Topic: Terpenes

Section: 23.3

Difficulty Level: Easy

144) When natural rubber is heated with sulfur, a reaction takes place that produces ___ between the polymer chains. This process is known as ___.

Topic: Terpenes

Section: 23.3

Difficulty Level: Easy

145) Diethylstilbestrol (DES) exhibits estradiol-like activity even though it is structurally unrelated to steroids. Once used widely as an additive in animal feed, DES has been implicated as a causative agent in several types of cancer. Show how DES can be drawn so that it is sterically similar to estradiol.

Topic: Steroids

Section: 23.4

Difficulty Level: Medium