Deck 23: Lipids

Question 1

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

Answer 1

Chloroform and diethyl ether

Question 2

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.

Answer 2

the physical operation done to isolate them; a variety of

Question 3

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.

Answer 3

Two of these choices are false statements.

Question 4

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

Question 5

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

Question 6

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

Question 7

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.

Question 8

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

Question 9

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

Question 10

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.

Question 11

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.

Question 12

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.

Question 13

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.

Question 14

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

Question 15

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.

Question 16

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

Question 17

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."

Question 18

What is likely to be a natural fatty acid?

A)Compounds I and IV
B)Only compound III
C)Compounds II and III
D)Compounds IV and V
E)Only compound II

Question 19

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

Question 20

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

Question 21

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)

Question 22

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.

Question 23

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

Question 24

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

Question 25

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.

Question 26

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

Question 27

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

Question 28

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)

Question 29

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

Question 30

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⁺

Question 31

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

A)CH₃(CH₂)₁₂COOH
B)CH₃(CH₂)₁₄COOH
C)
D)
E)

Question 32

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

Question 33

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

Question 34

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

Question 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

Question 36

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

A)
B)
C)
D)
E)

Question 37

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.

Question 38

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

Question 39

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.

Question 40

Which of these reagents would not react with oleic acid?

A)H₂,Ni
B)PBr₃
C)CH₃MgI
D)NH₃/H₂O
E)NaBH₄

Question 41

Which is the repeating unit of natural rubber?

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

Question 42

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

A)5 $\infty$ -Pregnane-3,20-dione
B)5 $\beta$ -Pregnane-3,20-dione
C)5 $\infty$ -Estrane-3,20-dione
D)5 $\beta$ -Estrane-3,20-dione
E)5 $\infty$ -Androstane-3,20-dione

Question 43

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

Question 44

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

Question 45

Which compound is a sesquiterpene?

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

Question 46

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

Question 47

Essential oils are constituted by

A)fatty acids and glycerol
B)triacylglycerol
C)terpenes only
D)glycerol
E)terpenoids and terpenes

Question 48

Which of these is a male sex hormone?

A)Estrone
B)Cholic acid
C)Testosterone
D)Cortisone
E)Estradiol

Question 49

In $\beta$ -carotene,how many tail-to-tail links of isoprene units are there?

A)1
B)2
C)3
D)4
E)More than 4

Question 50

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.

Question 51

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

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

Question 52

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

Question 53

Which reagent might be used to convert 5 $\infty$ -cholest-1-en-3-ol into 5 $\infty$ -cholestan-3-ol?

A)CrO₃/pyridine
B)KMnO₄/H₂O
C)CH₃MgI
D)H₂/Pt
E)Li/C₂H₅NH₂

Question 54

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

A)Monoterpenes
B)Sesquiterpenes
C)Diterpenes
D)Triterpenes
E)Tetraterpenes

Question 55

Which of the following is a female sex hormone?

A)Ergosterol
B)Estradiol
C)Cortisone
D)Androsterone
E)Cholic acid

Question 56

How many isoprene units are in vitamin A?

A)1
B)2
C)3
D)4
E)More than 4

Question 57

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

A)Ag(NH₃)₂⁺
B)CrO₃/H₂SO₄
C)Br₂/CCl₄
D)NaOH/H₂O
E)C₆H₅NHNH₂

Question 58

What product would be obtained by catalytic hydrogenation of 5-cholesten-3 $\beta$ -ol?

A)5 $\beta$ -Cholestan-3 $\beta$ -ol
B)5 $\beta$ -Cholestan-3 $\beta$ -ol.
C)5 $\infty$ -Cholestan-3 $\infty$ -ol
D)5 $\beta$ -Cholestan-3 $\infty$ -ol
E)5-Cholesten-3 $\beta$ ,6 $\infty$ -diol

Question 59

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.

Question 60

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

A)5 $\infty$ -Androstan-3 $\infty$ -ol
B)5 $\beta$ -Androstan-3 $\beta$ -ol
C)5 $\beta$ -Androstan-3 $\infty$ -ol
D)5 $\infty$ -Androstan-3 $\beta$ -ol
E)5 $\beta$ -Estan-3 $\beta$ -ol

Question 61

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.

Question 62

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.

Question 63

Which of the following is a phosphatidic acid?

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

Question 64

Which type of phosphatide has the structural unit:

A)Cephalins
B)Phosphatidyl serines
C)Plasmalogens
D)Lecithins
E)Both cephalins and plasmalogens

Question 65

How many stereogenic centers are there in cholesterol?

A)2
B)4
C)6
D)8
E)16

Question 66

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.

Question 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

Question 68

Which type of phosphatide contains the structural unit shown below?

A)Cephalins
B)Phosphatidyl serines
C)Plasmalogens
D)Lecithins
E)Both plasmalogens and lecithins

Question 69

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

Question 70

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

Question 71

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

Question 72

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

Question 73

Which of these is a wax?

A)
B)
C)
D)
E)CH₃(CH₂)₂₄CH₂OH

Question 74

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

Question 75

Which type of lipid gives these products on saponification? HOCH₂CHOHCH₂OH RCO₂¯ RCH₂CHO PO₄³¯ HOCH₂CH₂NH₂

A)Fat
B)Wax
C)Lecithin
D)Cephalin
E)Plasmalogen

Question 76

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.

Question 77

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

Question 78

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

A)17 $\infty$ ,21-Dihydroxypregna-1,4-diene-3,11,20-trione
B)17 $\beta$ ,21-Dihydroxypregna-1,4-diene-3,11,20-trione
C)17 $\infty$ ,19-Dihydroxypregna-1,4-diene-3,11,20-trione
D)17 $\beta$ ,19-Dihydroxypregna-1,4-diene-3,11,20-trione
E)17 $\infty$ ,21-Dihydroandrostan-1,4-diene-3,11,20-trione

Question 79

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

Question 80

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