Deck 19: Lipids

Question 1

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

Answer 1

dominated by hydrophobic regions

Question 2

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

Answer 2

Omega-3 acid

Question 3

Which is a nonhydrolyzable lipid?

A)A triacylglycerol
B)A wax
C)An eicosanoid
D)A phospholipid

Answer 3

An eicosanoid

Question 4

Which lipid has the lowest melting point?

A)
B)
C)
D)

Question 5

Which structural feature is not found in sphingomyelins?

A)An amide bond
B)A glycerol backbone
C)A phosphodiester
D)An alcohol

Question 6

Which lipid has the lowest melting point?

A)
B)
C)
D)

Question 7

Which is a hydrolyzable lipid?

A)A triacylglycerol
B)A steroid
C)An eicosanoid
D)A fat-soluble vitamin

Question 8

Which is a trans fat?

A)
B)
C)
D)

Question 9

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

Question 10

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

Question 11

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

A)Saturated
B)Monounsaturated
C)Polyunsaturated
D)Trans

Question 12

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

Question 13

What functional group is contained in most hydrolyzable lipids?

A)Amide
B)Ether
C)Ester
D)Carboxylic acid
E)Alkene

Question 14

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

Question 15

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

Question 16

Which is not an example of a lipid?

A)Phenol
B)Triacylglycerol
C)Cholesterol
D)Vitamin E

Question 17

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

Question 18

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

A)Saturated
B)Monounsaturated
C)Polyunsaturated
D)Trans

Question 19

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

Question 20

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

A)Enzymes
B)Bases
C)Oxidizing agents
D)Sulfuric acid

Question 21

Which structure is a sphingomyelin?

A)
B)
C)
D)

Question 22

Which structure is the steroid skeleton?

A)
B)
C)
D)

Question 23

Which is a hydrolyzable lipid?

A)A leukotriene
B)Cholesterol
C)A phosphoacylglycerol
D)Vitamin A

Question 24

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

Question 25

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.

Question 26

Which of these groups of compounds are phospholipids?

A)Leukotrienes
B)Fatty acids
C)Sphingomyelins
D)Adrenal cortical steroids

Question 27

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.

Question 28

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

A)
B)
C)
D)None of these represents a phosphoacylglycerol.

Question 29

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.

Question 30

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

Question 31

Which is not a fat-soluble vitamin?

A)Vitamin A
B)Vitamin C
C)Vitamin E
D)Vitamin K

Question 32

Which structure is a prostaglandin?

A)
B)
C)
D)

Question 33

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.

Question 34

Prostaglandins and leukotrienes are two types of ________.

A)low-density lipoproteins
B)eicosanoids
C)fat-soluble vitamins
D)adrenal cortical steroids

Question 35

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

Question 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

Question 37

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.

Question 38

Which is not an anabolic steroid?

A)Nandrolone
B)Cortisone
C)Stanozolol
D)Tetrahydrogestrinone

Question 39

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.

Question 40

What is the main component of the cell membrane?

A)Triacylglycerols
B)Phospholipids
C)Steroids
D)Waxes
E)Prostaglandins

Question 41

What is the structure of arachidic acid?

A)
B)
C)
D)

Question 42

How many fatty acids are required to form a triacylglycerol?

A)1
B)2
C)3
D)4

Question 43

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.

Question 44

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.

Question 45

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.

Question 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

Question 47

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.

Question 48

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

Question 49

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

Question 50

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

Question 51

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

Question 52

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

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

Question 53

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

Question 54

What is the structure of myristic acid?

A)
B)
C)
D)

Question 55

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

Question 56

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

Question 57

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

Question 58

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.

Question 59

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)

Question 60

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

Question 61

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

Question 62

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.

Question 63

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

Question 64

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

Question 65

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

Question 66

The compound below is an example of a simple triacylglycerol.

Question 67

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

Question 68

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

Question 69

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

Question 70

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

Question 71

Hydrolysis of the triacylglycerol below provides the indicated products.

Question 72

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

Question 73

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

Question 74

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

Question 75

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.

Question 76

The compound below is a phospholipid classified as a lecithin.

Question 77

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

Question 78

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.

Question 79

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

Question 80

Hydrolysis of the triacylglycerol below provides the indicated products.