Chem 1152 Chapter 28: Lipids

49. What type of lipid is represented below? a) A triacylglycerol b) A prostaglandin c) A wax d) A sphingolipid

c) A wax

39. Select the picture that best represents the structure of a lipid bilayer.

Lipid bilayer

47. What type of lipid is shown below? a) A fatty acid b) A thromboxane c) A fat d) A steroid

a) A fatty acid

52. What type of lipid is represented below? a) A phospholipid b) A phosphatidic acid c) A wax d) A triacylglycerol

a) A phospholipid

48. What type of lipid is represented below? a) A triacylglycerol b) A prostaglandin c) A wax d) A sphingolipid

a) A triacylglycerol

26. What is the defining characteristic of a lipid? a) All lipids are soluble in non-polar organic solvents. b) All lipids have structures based on a system of four fused carbon rings. c) All lipids have sulfur atoms in their structure. d) All lipids are esters.

a) All lipids are soluble in non-polar organic solvents.

31. Which of the following molecules is the parent molecule for steroids? a) Cholesterol b) Sphingosine c) Arachidonic acid d) Glucose

a) Cholesterol

30. What is the difference between saturated fatty acids and unsaturated fatty acids? a) Unsaturated fatty acids have double bonds, saturated fatty acids do not. b) Unsaturated fatty acids have an even number of carbons, saturated fatty acids have an odd number of carbons. c) Unsaturated fatty acids have cis double bonds, saturated fatty acids have trans double bonds. d) Unsaturated fatty acids are naturally occurring compounds, saturated fatty acids do not occur in nature and must be prepared synthetically.

a) Unsaturated fatty acids have double bonds, saturated fatty acids do not

44. Which of the following best describe the composition of lecithin? a) contains glycerol + 2 fatty acids + phosphoric acid + choline b) contains glycerol + 2 fatty acids + phosphoric acid c) contains glycerol + 3 fatty acids d) contains glycerol + 3 fatty acids

a) contains glycerol + 2 fatty acids + phosphoric acid + choline

41. Which of the following best describe the composition of sphingomyelin? a) contains sphingosine + 1 fatty acid + +Phosphoric acid + choline b) contains sphingosine + +Phosphoric acid + choline c) contains sphingosine + 1 fatty acid + galactose d) contains sphingosine + galactose

a) contains sphingosine + 1 fatty acid + +Phosphoric acid + choline

29. A sphingolipid always contains: a) sphingosine b) choline c) phosphatidic acid d) three fatty acids

a) sphingosine

51. Which statement is the most accurate? a) On average humans store about one week of energy as fat b) On average humans store about two to three weeks of energy as fat c) On average humans store about five to six weeks of energy as fat d) On average humans store about ten to twelve weeks of energy as fat

b) On average humans store about two to three weeks of energy as fat

37. Which of the following is not true of waxes? a) Some of them protect leaves and fruits. b) They tend to be soft because of the long carbon chains. c) They contain an ester bond. d) They are one of the most hydrophobic classes of lipids.

b) They tend to be soft because of the long carbon chains

25. For a compound to be classed as a lipid, it must: a) contain a glycerol unit b) be soluble in nonpolar solvents c) contain at least one fatty acid unit d) be soluble in water

b) be soluble in nonpolar solvents

33. The following is not involved in cholesterol transport. a) high density lipoprotein b) low density sterolprotein c) very low density lipoprotein d) low density lipoprotein

b) low density sterolprotein

50. Which statement is the most accurate? a) Fat molecules are approximately 25% carbon by mass b) Fat molecules are approximately 50% carbon by mass c) Fat molecules are approximately 75% carbon by mass d) Fat molecules are approximately 100% carbon by mass

c) Fat molecules are approximately 75% carbon by mass

34. Which of the following is not a characteristic of a cell membrane? a) The bilayer interior is formed from the hydrophobic regions of two adjoining layers of lipid molecules. b) The surface of the membrane is hydrophilic. c) Most of the membrane is composed of phospholipid. d) Proteins allow the transport of hydrophilic substances across the membrane.

c) Most of the membrane is composed of phospholipid.

40. What effect does the inclusion of cholesterol in a lipid bilayer membrane have on the properties of the membrane? a) The inclusion of cholesterol in the lipid bilayer allows the membrane to remain fluid and flexible at low temperatures. b) The inclusion of cholesterol in the lipid bilayer makes the membrane more permeable to polar molecules. c) The inclusion of cholesterol in the lipid bilayer adds rigidity to the membrane. d) The inclusion of cholesterol in the lipid bilayer blocks the transport of small polar molecules

c) The inclusion of cholesterol in the lipid bilayer adds rigidity to the membrane.

38. Which of the following is not true about phospholipids? a) They contain two fatty acid molecules. b) They have a hydrophobic region and a hydrophilic region. c) They contain three fatty acid molecules. d) They are found in cell membranes. Answer: c; Difficulty: Moderate; Reference: 28.5

c) They contain three fatty acid molecules.

42. Which of the following best describe the composition of cerebroside? a) contains sphingosine + 1 fatty acid + +Phosphoric acid + choline b) contains sphingosine + +Phosphoric acid + choline c) contains sphingosine + 1 fatty acid + galactose d) contains sphingosine + galactose

c) contains sphingosine + 1 fatty acid + galactose

27. A cephalin is also known as: a) sphingomyelin b) phosphatidyl serine c) phosphatidyl ethanolamine d) phosphatidyl choline

c) phosphatidyl ethanolamine

36. Which substance below is not a simple lipid? a) fat b) oil c) phospholipid d) wax

c) phospholipid

46. Which of the following compound lipids are not found in biological membranes? a) glycolipids b) cephalins c) steroids d) lecithins

c) steroids

53. Which is present in biological membranes? a) Phospholipids b) Sphingolipids c) Glycolipids d) Phospholipids, sphingolipids, and glycolipids are present in biological membranes

d) Phospholipids, sphingolipids, and glycolipids are present in biological membranes

45. Which of the following is not a type of compound lipid? a) Phospholipid b) Sphingolipid c) Glycolipid d) Steroid

d) Steroid

43. Which of the following best describe the composition of oil? a) contains 1 long chain fatty acid + a long chain alcohol b) contains 3 saturated fatty acid units c) contains 3 unsaturated fatty acid units d) contains glycerol +3 fatty acids

d) contains glycerol +3 fatty acids

35. Waxes are composed of: a) glycerol and three long-chain fatty acids. b) glycerol, two fatty acids and phosphoric acid. c) two fatty acids. d) one long chain fatty acid and one long chain alcohol

d) one long chain fatty acid and one long chain alcohol

28. Phosphatidyl choline is an example of a: a) glycolipid b) wax c) triacylglycerol d) phospholipid

d) phospholipid

32. Cholesterol is a: a) fat b) glycolipid c) phospholipid d) steroid

d) steroid