Test Bank Answers Lipids Chapter 19

General, Organic and Biological Chemistry, 4e (Smith)

Chapter 19 Lipids

1) Which is not an example of a lipid?

A) Phenol

B) Triacylglycerol

C) Cholesterol

D) Vitamin E

2) Which is a hydrolyzable lipid?

A) A triacylglycerol

B) A steroid

C) An eicosanoid

D) A fat-soluble vitamin

3) Which is a nonhydrolyzable lipid?

A) A triacylglycerol

B) A wax

C) An eicosanoid

D) A phospholipid

4) What functional group is contained in most hydrolyzable lipids?

A) Amide

B) Ether

C) Ester

D) Carboxylic acid

E) Alkene

5) The structure of lipids is ________.

A) dominated by ionic regions

B) dominated by hydrophilic regions

C) dominated by hydrophobic regions

D) equally dominated by hydrophilic and hydrophobic regions

6) What designation best describes linolenic acid, whose structure is shown below?

A) Omega-6 acid

B) Omega-3 acid

C) Omega-9 acid

D) Omega-1 acid

7) What designation best describes linoleic acid, whose structure is shown below?

A) Omega-6 acid

B) Omega-3 acid

C) Omega-9 acid

D) Omega-1 acid

8) Which compound has the highest melting point?

A) CH3(CH2)14COOH

B) CH3(CH2)10CH=CH(CH2)2COOH

C) CH3(CH2)2CH=CH(CH2)4CH=CH(CH2)4COOH

D) CH3(CH2)2CH=CH(CH2)2CH=CH(CH2)2CH=CH(CH2)2COOH

9) Which compound has the lowest melting point?

A) CH3(CH2)18COOH

B) CH3(CH2)5CH=CH(CH2)7COOH

C) CH3(CH2)7CH=CH(CH2)7COOH

D) CH3(CH2)4(CH=CHCH2)4(CH2)2COOH

10) The compound shown below is classified as what type of a lipid?

A) A fatty acid

B) A wax

C) An eicosanoid

D) A triglyceride

11) Waxes are formed from the reaction between which two types of compounds?

A) A fatty acid and an amide

B) A high molecular weight alcohol and an ester

C) A fatty acid and a high molecular weight alcohol

D) An ester and a fatty acid

12) Which type of fatty acid is most common in olive oil?

A) Saturated

B) Monounsaturated

C) Polyunsaturated

D) Trans

13) Unlike most oils, which type of fatty acid is most common in coconut oil?

A) Saturated

B) Monounsaturated

C) Polyunsaturated

D) Trans

14) Hydrolysis of triacylglycerols in the body occurs with the aid of which reagent?

A) Enzymes

B) Bases

C) Oxidizing agents

D) Sulfuric acid

15) Which is a trans fat?

A)

B)

C)

D)

16) Which lipid has the lowest melting point?

A)

B)

C)

D)

17) Which lipid has the lowest melting point?

A)

B)

C)

D)

18) Complete metabolism of a triacylglycerol yields which of the following?

A) Glycerol, fatty acids, and a great deal of energy

B) Fatty acids and a great deal of energy

C) Fatty acids, H2O, and a great deal of energy

D) CO2, H2O, and a great deal of energy

19) Which structural feature is not found in sphingomyelins?

A) An amide bond

B) A glycerol backbone

C) A phosphodiester

D) An alcohol

20) What process is used to move large polar molecules and ions, such as Cl– and HCO3–, through a cell membrane, traveling from the side of higher concentration to the side of lower concentration?

A) Facilitated transport

B) Diffusion

C) Active transport

D) Effusion

21) Which structure is the steroid skeleton?

A)

B)

C)

D)

22) Which statement is not true?

A) Cholesterol is the most prominent member of the steroid family.

B) Cholesterol is insoluble in the aqueous medium of the blood.

C) Cholesterol serves as the starting material for the synthesis of all other steroids.

D) Cholesterol is a vital component for healthy cell membranes.

E) Cholesterol cannot be synthesized in the body, and therefore is required in the diet.

23) Which is not an anabolic steroid?

A) Nandrolone

B) Cortisone

C) Stanozolol

D) Tetrahydrogestrinone

24) Which statement correctly describes the hydroxyl (-OH) groups found in the steroid prednisone (structure shown)?

A) There is one primary alcohol group and one secondary alcohol group.

B) There is one secondary alcohol group and one tertiary alcohol group.

C) There is one primary alcohol group and one tertiary alcohol group.

D) There is one tertiary alcohol group and one carboxylic acid.

25) Which statement correctly describes the hydroxyl (-OH) group found in the steroid cholesterol?

A) It is a primary alcohol.

B) It is a secondary alcohol.

C) It is a tertiary alcohol.

D) It is the OH group of a carboxylic acid.

26) Which is not a fat-soluble vitamin?

A) Vitamin A

B) Vitamin C

C) Vitamin E

D) Vitamin K

27) Which vitamin is not strictly a vitamin because it can be synthesized in the body from cholesterol?

A) Vitamin A

B) Vitamin E

C) Vitamin K

D) Vitamin D

28) Which statement is not true?

A) Vitamin A is obtained from liver, oily fish, and dairy products.

B) Vitamin E is an oxidizing agent, oxidizing the unsaturated side chains in fatty acids.

C) A severe deficiency of vitamin K leads to excessive and sometimes fatal bleeding, because of inadequate blood clotting.

D) Vitamin D helps regulate both calcium and phosphorus metabolism.

29) Which is not true about prostaglandins?

A) Prostaglandins decrease gastric secretions.

B) Prostaglandins decrease inflammation.

C) Prostaglandins inhibit blood platelet aggregation.

D) Prostaglandins stimulate uterine contractions.

E) Prostaglandins relax the smooth muscles of the uterus.

30) Prostaglandins and leukotrienes are two types of ________.

A) low-density lipoproteins

B) eicosanoids

C) fat-soluble vitamins

D) adrenal cortical steroids

31) What is the main component of the cell membrane?

A) Triacylglycerols

B) Phospholipids

C) Steroids

D) Waxes

E) Prostaglandins

32) Which is a hydrolyzable lipid?

A) A leukotriene

B) Cholesterol

C) A phosphoacylglycerol

D) Vitamin A

33) Which of these groups of compounds are phospholipids?

A) Leukotrienes

B) Fatty acids

C) Sphingomyelins

D) Adrenal cortical steroids

34) Which structure is a prostaglandin?

A)

B)

C)

D)

35) Which structure is a sphingomyelin?

A)

B)

C)

D)

36) Lovastatin (structure shown) was the first statin drug to be marketed and used for lowering blood cholesterol. Which of the following functional groups is not present in lovastatin?

A) Ketone

B) Ester

C) Alcohol

D) Alkene

37) Testosterone (structure shown) is an androgen that control the development of secondary sex characteristics in males. Which of the following functional groups is not present in testosterone?

A) Ketone

B) Carboxylic acid

C) Alcohol

D) Alkene

38) Lovastatin (structure shown) was the first statin drug to be marketed and used for lowering blood cholesterol. How many chirality centers are present in lovastatin?

A) 4

B) 7

C) 8

D) 9

E) There are more than ten (10) chirality centers in lovastatin.

39) Simvastatin, also sold as Zocor (structure shown), is a drug used to reduce the level of cholesterol in the bloodstream. Which of the following functional groups is not present in simvastatin?

A) Ketone

B) Ester

C) Alcohol

D) Alkene

40) Which "cartoon" best represents the structure of a phosphoacylglycerol?

A)

B)

C)

D) None of these represents a phosphoacylglycerol.

41) What hydrolysis products are formed when the wax CH3(CH2)18COO(CH2)17CH3 is treated with aqueous sulfuric acid?

A) CH3(CH2)18CHO + CH3(CH2)16CH2OH

B) CH3(CH2)18COOH + CH3(CH2)16CH2OH

C) CH3(CH2)18COOH + CH3(CH2)16CH3

D) CH3(CH2)18COOH + CH3(CH2)16COOH

E) CH3(CH2)18CH2OH + CH3(CH2)16COOH

42) What wax is formed from palmitic acid [CH3(CH2)14COOH] and the alcohol CH3(CH2)21OH?

A) CH3(CH2)21COO(CH2)14CH3

B) CH3(CH2)14COO(CH2)14CH3

C) CH3(CH2)14COO(CH2)21CH3

D) CH3(CH2)21COO(CH2)21CH3

43) What is the structure of myristic acid?

A)

B)

C)

D)

44) What is the structure of arachidic acid?

A)

B)

C)

D)

45) The compound shown below is best classified as what type of lipid?

A) A triacylglycerol

B) A soap

C) A fatty acid

D) A wax

46) The compound shown below is best classified as what type of lipid?

A) A triacylglycerol

B) A soap

C) A fatty acid

D) A wax

47) The compound shown below is best classified as what type of lipid?

A) A triacylglycerol

B) A soap

C) A fatty acid

D) A wax

48) How many triacylglycerols can be prepared from two different fatty acids?

A) 2

B) 4

C) 6

D) 8

49) How many fatty acids are required to form a triacylglycerol?

A) 1

B) 2

C) 3

D) 4

50) Which statement concerning lipid functions is incorrect?

A) Steroid hormones act as messenger molecules and regulate biochemical processes.

B) Phospholipids, glycolipids, and cholesterol provide structure for cell membranes.

C) Triacylglycerols are used for long term energy storage.

D) Plants and animals use waxes for insulation.

51) Fats and oils are structurally both triacylglycerols, but fats are solids at room temperature and oils are liquids at room temperature. Which statement best describes the reason for their difference in physical state?

A) Fats are simple triacylglycerols and oils are mixed triacylglycerols.

B) Oils are simple triacylglycerols and fats are mixed triacylglycerols.

C) Oils contain longer fatty acid chains than fats do, and therefore have higher melting points than fats.

D) Fats contain a higher percentage of saturated fatty acids than oils do, and therefore have higher melting points than oils.

52) The block diagram for a phosphoacylglycerol (glycerophospholipid) is shown below. Phosphoacylglycerols can interact with both water and other lipids, and therefore are well suited for their role in the lipid bilayer of cell membranes. Which statement best explains this behavior?

A) They contain a phosphodiester.

B) They contain both a hydrophobic region as well as a hydrophilic region.

C) They contain both saturated fatty acids as well as unsaturated fatty acids.

D) They contain both single bonds as well as double bonds.

53) Cetyl palmitate is a component of spermaceti wax isolated from the heads of sperm whales, and is used in cosmetics. In which solvent would cetyl palmitate be expected to have the greatest solubility?  

A) Acetic acid

B) Ethanol

C) Hexane

D) Water

54) Glycerol, shown below, is a component of triacylglycerols. In which solvent would glycerol be expected to have the greatest solubility?

A) Octane

B) Benzene

C) Hexane

D) Water

55) The contents on a box of cupcakes lists partially hydrogenated soybean oil. Partial hydrogenation of soybean oil has what effect?

A) It produces fatty acid salts.

B) It decreases the percent of unsaturation that is present.

C) It hydrolyzes the triacylglycerol.

D) It increases the number of fatty acids present.

56) Stearin is a triglyceride derived from three units of stearic acid, an 18-carbon fatty acid. Which of the structures below represents stearin?

A)

B)

C)

D)

57) Tamoxifen is a widely used anti-estrogen drug used to treat tumors of the breast. Tamoxifen would be considered a hydrophilic molecule, having limited solubility in water and blood, and high solubility in fat. 

58) The fatty acid shown below will be a solid at room temperature.

59) The fatty acid shown below will be a solid at room temperature.

60) Fats contain a larger percentage of unsaturation in their structures than oils do.

61) Trans double bonds can be formed when triacylglycerols are partially hydrogenated.

62) The compound below is an example of a simple triacylglycerol.

63) The three-dimensional structure of a trans triacylglycerol shows its similarity to saturated triacylglycerols.

64) Hydrolysis of the triacylglycerol below provides the indicated products.

65) Hydrolysis of the triacylglycerol below provides the indicated products.

66) Although biofuels are prepared from renewable resources such as vegetable oils and animal fats, they still burn to form CO2, a gas that contributes to global warming.

67) Soap is prepared by the acid hydrolysis (saponification) of a triacylglycerol.

68) The compound below is a phospholipid classified as a lecithin.

69) The compound below is the amino alcohol known as sphingosine, which forms the backbone of sphingomyelins.

70) The coating that surrounds and insulates nerve cells, the myelin sheath, is particularly rich in sphingomyelins, and is vital for proper nerve function.

71) A sphingomyelin has three nonpolar side chain tails and one polar head.

72) When phospholipids are mixed with water, they assemble in an arrangement called a lipid bilayer, with the ionic heads oriented on the inside and the nonpolar tails on the outside.

73) Some lipids and proteins on the cell membrane surface are bonded to carbohydrates, forming glycolipids and glycoproteins.

74) In order for cholesterol to be transported from where it is synthesized in the liver to the tissues, it combines with phospholipids and proteins to form small water-soluble spherical particles called lipozymes.

75) High-density lipoproteins (HDLs) transport cholesterol from where it is synthesized, to the tissues.

76) Aldosterone regulates blood pressure and volume by controlling the concentration of Na+ and K+ in body fluids.

77) Vitamins are organic compounds required in small quantities for normal metabolism.

78) Prostaglandins are a group of carboxylic acids that contain a five-membered ring, and are responsible for inflammation.

79) Eicosanoids are a group of biologically active compounds containing 20 carbon atoms derived from the fatty acid arachidonic acid.

80) The compound below is a mixed triacylglycerol formed from lauric, myristic, and linoleic acids.

81) The compound below is a mixed triacylglycerol formed from oleic, stearic, and palmitic acids.

82) Phosphoacylglycerols are less soluble in water than triacylglycerols.

83) The triacylglycerol shown below is expected to be a liquid at room temperature.

84) The triacylglycerol shown below is expected to be a liquid at room temperature.

85) Triacylglycerols form lipid bilayers.

86) There are twenty-one (21) tetrahedral carbons in Vitamin D4 (structure shown).

87) There are six (6) trigonal planar carbons in Vitamin D4 (structure shown).

88) There is only one polar bond in Vitamin D4 (structure shown).

89) There are ten (10) tetrahedral carbons in Vitamin A (structure shown).

90) There are eight (8) trigonal planar carbons in Vitamin A (structure shown).

91) There are two polar bonds in Vitamin A (structure shown).

92) Zileuton (Zyflo) treats the cause of asthma, not just its symptoms, by blocking the synthesis of leukotriene C4.

93) Aspirin and celecoxib act as anti-inflammatory agents by inactivating both the COX-1 and COX-2 enzymes.

94) An individual can survive on a completely fat-free diet.

95) The structure shown below is an example of a trans fatty acid.

96) Lipids are defined as biomolecules that contain fatty acids as part of their structure.

97) Lipids come in a wide variety of structures and have many different functions.

98) Lipids are soluble in organic solvents and aqueous solutions.

99) Saturated fatty acids have no double bonds in their long hydrocarbon chains.

100) The most common unsaturated fatty acids are palmitic and stearic acid.

101) Unsaturated fatty acids are sometimes classified as omega-n acids, where n is the carbon at which the first double bond occurs in the carbon chain, beginning at the end of the chain that contains the CH3 group.

102) The molecule below is an omega–9 fatty acid.

103) The molecule below is an omega–9 fatty acid.

CH3(CH2)9CH=CH(CH2)7COOH

104) Cell membranes are made up of a structure called a(n) ________.

105) As the number of double bonds in a fatty acid increases, the melting point ________.

106) ________ are the simplest hydrolyzable lipids.

107) Triacylglycerols, or triglycerides, are triesters formed from glycerol and three ________ molecules.

108) Triacylglycerols are stored in ________ cells below the skin and concentrated in some regions of the body.

109) Two common types of phospholipids are ________ and ________.

110) The ________ is the aqueous medium inside the cell, separated from water outside the cell by the cell membrane.

111) Estradiol and estrone are two estrogen hormones synthesized in the ________.

112) There are ________ chirality centers in prednisone (structure shown).

113) There are ________ chirality centers in Vitamin A (structure shown).

114) Lipids known as ________ provide a protective coating for plants and animals.

115) The name of the wax formed in the reaction between palmitic acid and cetyl alcohol is ________.