BSC450 Ch8

What is the abbreviated nomenclature for octadecanoic acid with two double bonds?

18:2

Which statement concerning fatty acids is CORRECT?

A fatty acid is the precursor of prostaglandins.

What is the abbreviated nomenclature for a 14-carbon omega-3 fatty acid that contains no other double bonds? A) 14:1(Delta 11) B) 17:1(Delta 14) C) 14:1(Delta 3) D) 13:1(Delta 11) E) 14:0(Delta 11)

A) 14:1(Delta 11)

Which statement concerning fatty acids is CORRECT? A) A fatty acid is the precursor of prostaglandins. B) Phosphatidic acid is a common fatty acid. C) Fatty acids all contain one or more double bonds. D) Fatty acids are a constituent of sterols. E) Fatty acids are strongly hydrophilic.

A) A fatty acid is the precursor of prostaglandins.

Which statement about sterols is TRUE? A) All sterols share a fused-ring structure with four rings. B) Sterols are found in the membranes of all living cells. C) Sterols are soluble in water, but less so in organic solvents such as chloroform. D) Cholesterol is the principal sterol in fungi. E) The principal sterol of animal cells is ergosterol.

A) All sterols share a fused-ring structure with four rings.

Which statement describes a distinct difference between membrane lipids in archaea and membrane lipids in eukarya? A) Archaeal membrane lipids have alkyl acids that are ether-linked to glycerol at both ends. B) Eukaryotic membrane lipids consist of glycerol that is ester-linked to three fatty acids. C) Only eukaryotic membrane lipids are amphipathic. D) Archaeal membrane lipids always contain sphingosine. E) Eukaryotic membrane lipids always have a phosphate group attached to glycerol.

A) Archaeal membrane lipids have alkyl acids that are ether-linked to glycerol at both ends.

Which statement is TRUE of sphingolipids? A) Cerebrosides and gangliosides are sphingolipids. B) Phosphatidylcholine is a typical sphingolipid. C) They always contain glycerol and fatty acids. D) They contain two esterified fatty acids. E) They may be charged, but are never amphipathic.

A) Cerebrosides and gangliosides are sphingolipids.

Which statement BEST describes how the volatility of lipids is increased for analysis by gas chromatography? A) The lipids are transesterified to convert fatty acids into fatty acid methyl esters. B) The lipids are cleaved with phospholipase enzymes . C) The lipids are degraded by treatment with mild acid or base. D) The lipids are dissolved in chloroform. E) The lipids are desaturated by reaction with a platinum catalyst.

A) The lipids are transesterified to convert fatty acids into fatty acid methyl esters.

Which term BEST describes the cholesterol molecule? A) amphipathic B) nonpolar, charged C) nonpolar, uncharged D) polar, charged E) polar, uncharged

A) amphipathic

Sphingosine is NOT a component of: A) cardiolipin. B) ceramide. C) cerebrosides. D) gangliosides. E) sphingomyelin.

A) cardiolipin.

Bile acids are derived from which lipid? A) cholesterol B) sphingomyelin C) ceramide D) digalactosyldiacylglycerol E) phosphatidylcholine

A) cholesterol

Tay-Sachs disease is the result of a genetic defect in the metabolism of: A) gangliosides. B) phosphatidyl ethanolamine. C) sterols. D) triacylglycerols. E) vitamin D.

A) gangliosides.

Which technique would you NOT use to separate and/or analyze lipids in a laboratory? A) gel electrophoresis B) thin-layer chromatography C) adsorption chromatography D) mass spectrometry E) high-performance liquid chromatography (HPLC)

A) gel electrophoresis

Which molecules or substances contain, or are derived from, fatty acids?

All of these contain or are derived from fatty acids.

Which statement about sterols is TRUE?

All sterols share a fused-ring structure with four rings.

Which vitamin is NOT fat soluble? A) A B) C C) D D) E E) K

B) C

Which statement BEST describes why lipids typically float on water? A) Lipids are nonpolar, while water is polar. B) Lipids have lower specific gravities than water does. C) Lipids have higher melting temperature than water does. D) Lipids store more energy than water does. E) Lipids contain carbon, while water does not.

B) Lipids have lower specific gravities than water does.

Which statement is TRUE of lipids? A) Many contain fatty acids in ester or amide linkage. B) Most are simply polymers of isoprene. C) Testosterone is an important sphingolipid found in myelin. D) They are more soluble in water than in chloroform. E) They play only passive roles as energy-storage molecules.

B) Most are simply polymers of isoprene.

Which statement is NOT true? A) Phospholipase A1 hydrolyzes the fatty acid from the 1-position on the glycerol backbone. B) Phospholipase B1 hydrolyzes the fatty acid from the 2-position on the glycerol backbone. C) Phospholipase C hydrolyzes the complete phospho-head group from the glycerol backbone. D) Phospholipase D hydrolyzes just the head group from the phospho-glycerol backbone.

B) Phospholipase B1 hydrolyzes the fatty acid from the 2-position on the glycerol backbone.

Which statement is NOT true of sterols? A) Cholesterol is a sterol that is commonly found in mammals. B) Sterols are commonly found in bacterial membranes. C) Sterols are more common in plasma membranes than in intracellular membranes (mitochondria, lysosomes, etc.). D) Serols are precursors of steroid hormones. E) Sterols have a structure that includes four fused rings.

B) Sterols are commonly found in bacterial membranes.

Which feature allows certain lipid molecules to be used as colorful pigments in plants and animals? A) Their high oxygen content helps electrons circulate, which allows absorption of visible light. B) Their conjugated bond structures allow absorption of visible light. C) Their four-fused ring structure allows visible light reflection. D) Their hydrophobicity bends light around them. E) Their low specific gravities cause light to reflect from their surfaces.

B) Their conjugated bond structures allow absorption of visible light.

Fatty acids are attached to sphingosine by what type of chemical linkage? A) an ether linkage B) an amide linkage C) an ester linkage D) a peroxide linkage E) a alkyl linkage

B) an amide linkage

Which compound can be cleaved in half to generate a molecule important in vision? A) calcitol B) beta-carotene C) arachidonic acid D) tocopherol E) isoprene

B) beta-carotene

Fatty acids are a component of: A) carotenes. B) cerebrosides. C) sterols. D) vitamin D. E) vitamin K.

B) cerebrosides.

The steroid hormones testosterone and beta-estradiol are derived from which lipid molecule? A) phosphatidylcholine B) cholesterol C) lipoxin A D) arachidonic acid E) geraniol

B) cholesterol

What feature do Tay-Sachs disease, Fabry disease, and Niemann-Pick disease have in common? A) defects in enzymes responsible for synthesizing membrane lipids B) defects in enzymes responsible for breaking down membrane lipids in the lysosomes C) hyperactive membrane lipid degradation enzymes D) defects in enzymes responsible for cholesterol synthesis E) All of the answers are correct.

B) defects in enzymes responsible for breaking down membrane lipids in the lysosomes

Waxes are BEST described as: A) esters of glycerol and three fatty acids. B) esters of one long-chain fatty acid and one long-chain alcohol. C) polyunsaturated long-chain fatty acids. D) esters of two long-chain fatty acids. E) ethers of glycerol and short-chain alcohols.

B) esters of one long-chain fatty acid and one long-chain alcohol.

Biological waxes are all: A) triesters of glycerol and palmitic acid. B) esters of single fatty acids with long-chain alcohols. C) triesters of glycerol and three long chain saturated fatty acids. D) sphingolipids. E) None of the answers is correct.

B) esters of single fatty acids with long-chain alcohols.

A compound containing N-acetylneuraminic acid (sialic acid) is: A) cardiolipin. B) ganglioside GM2. C) phosphatidylcholine. D) platelet-activating factor. E) sphingomyelin.

B) ganglioside GM2.

Which molecule is MOST commonly used as a backbone the linkage of three fatty acids to form fats? A) glycogen B) glycerol C) sphingosine D) glucose E) phosphoglycerol

B) glycerol

Which types of membrane lipids are modified to determine blood type in humans? A) phosphatidylserines B) glycosphingolipids C) galactolipids D) plasmalogens E) sphingomyelins

B) glycosphingolipids

Which method can be used to visualize lipids that have been separated by thin-layer chromatography by reversibly reacting with double bonds in fatty acids? A) ethanol B) iodine fumes C) low-wavelength UV light D) rhodamine E) ethidium bromide

B) iodine fumes

Platelet-activating factor is much more water soluble than most other glycerophospholipids due to which feature? A) its ether-linked alkyl chain at the C-1 of glycerol B) its ester-linked acetic acid at the C-2 of glycerol C) its ethanolamine head group D) its lack of any long alkyl chains linked to glycerol E) the presence of sphingosine, rather than glycerol, as a lipid backbone

B) its ester-linked acetic acid at the C-2 of glycerol

Human adipocytes contain which enzyme that catalyzes the breakdown of triacylglycerols? A) glycerase B) lipase C) fatase D) esterase E) triacylase

B) lipase

The study and classification of the complete set of lipids produced in an organisms is called: A) proteomics. B) lipidomics. C) genomics. D) lipidification. E) fatification.

B) lipidomics.

Which factor is NOT a consequence of partial hydrogenation of vegetable oils? A) longer shelf life B) lower melting temperature C) reduction of some cis double bonds to single bonds D) conversion of some cis double bonds to trans double bonds E) increased risk of cardiovascular disease upon consumption by humans

B) lower melting temperature

If you wanted to analyze membrane lipids from a biological sample, which solvent would MOST effectively extract those lipids? A) benzene B) methanol C) water D) chloroform E) ethyl ether

B) methanol

In high-performance liquid chromatography of lipid mixtures using a column packed with a silica gel, which types of lipids will elute first? A) positively charged lipids B) neutral lipids C) negatively charged lipids D) polar lipids E) zwitterionic lipids

B) neutral lipids

Nonsteroidal anti-inflammatory drugs (NSAIDS) like aspirin and ibuprofen act by blocking production of: A) biological waxes B) prostaglandins C) sphingolipids D) vitamin D E) None of the answers is correct.

B) prostaglandins

Which eicosanoids contains a five-carbon ring as part of its structure? A) thromboxanes B) prostaglandins C) lipoxins D) leukotrienes E) arachidonates

B) prostaglandins

Which types of signaling lipids are produced by platelets to aid in the formation of blood clots? A) prostaglandins B) thromboxanes C) arachidonates D) lipoxins E) leukotrienes

B) thromboxanes

Which solvent is NOT used to dissolve lipids? A) ethyl ether B) water C) benzene D) methanol E) chloroform

B) water

Triacylglycerols are composed of:

Both glycerol backbone and three fatty acids

Which vitamin is NOT fat soluble?

C

What is the abbreviated nomenclature for octadecanoic acid with two double bonds? A) 16:1 B) 14:2 C) 18:2 D) 18:0 E) 18:1

C) 18:2

Which vitamin is derived from cholesterol? A) A B) B12 C) D D) E E) K

C) D

Which solvent is a commonly used to extract all the lipids from homogenized tissue samples and subsequent separation of the lipids from the proteins and sugars present in those samples? A) ethanol B) benzene C) a mixture of chloroform, methanol, and water D) water E) a mixture of chloroform and benzene

C) a mixture of chloroform, methanol, and water

Which term BEST describes the polarity of membrane lipids? A) ambidextrous B) completely nonpolar C) amphipathic D) completely polar E) amphibolic

C) amphipathic

Which type of chemical linkage is used to join fatty acids to glycerol? A) an ether linkage B) a peptide bond C) an ester linkage D) a double bond E) a peroxide bond

C) an ester linkage

Which types of membrane lipids make up 70% to 80% of the total membrane lipids in a vascular plant? A) phosphatidylserines B) glycosphingolipids C) galactolipids D) plasmalogens E) sphingomyelins

C) galactolipids

You are working in a laboratory trying to design a drug that specifically binds to the surface of certain cells. To which membrane lipid constituents should your drug bind in order to achieve this specificity? A) sphingomyelins B) phosphatidylcholines C) gangliosides D) triacylglycerols E) sterols

C) gangliosides

Commercial vegetable oils can be converted from liquid forms to solid forms and have their shelf lives increased due to which process? A) partial desaturation B) unsaturation C) partial hydrogenation D) hydrolysis E) complete esterification

C) partial hydrogenation

Which glycerophospholipid has a net charge of zero at pH 7? A) phosphatidylserine B) phasphatidic acid C) phosphatidylcholine D) phosphatidylglycerol E) phosphatidylinositol 4,5-bisphosphate

C) phosphatidylcholine

Which membrane lipid serves as a reservoir of messenger molecules for signal transduction? A) taruocholic acid (TA) B) phosphatidylserine (PS) C) phosphatidylinositol 4,5-bisphosphate (PIP2) D) thromboxane A2 (TXA2) E) sphingomyelin (SM)

C) phosphatidylinositol 4,5-bisphosphate (PIP2)

An example of a glycerophospholipid that is involved in cell signaling is: A) arachidonic acid. B) ceramide. C) phosphatidylinositol. D) testosterone. E) vitamin A (retinol).

C) phosphatidylinositol.

Which technique is NOT commonly used to analyze lipid composition? A) selective extraction using apolar solvents B) adsorption chromatography C) x-ray crystallography D) hydrolysis using enzymes with specificity for certain linkages E) mass spectroscopy

C) x-ray crystallography

Which statement is TRUE of sphingolipids?

Cerebrosides and gangliosides are sphingolipids.

Which vitamin is derived from cholesterol?

D

Which statement is TRUE about fatty acids? A) Fatty acids with longer chains have higher melting points. B) Fatty acids with longer chains have lower solubility in water. C) Fatty acids with more double bonds have higher melting points. D) Fatty acids with longer chains have higher melting points and lower solubility in water. E) None of the statements is true.

D) Fatty acids with longer chains have higher melting points and lower solubility in water.

_____ is NOT a biological use of waxes. A) Energy storage B) Lubrication C) Structure D) Insulation E) Waterproofing

D) Insulation

_____ contain(s) an ether-linked alkyl group. A) Cerebrosides B) Gangliosides C) Phosphatidyl serine D) Platelet-activating factor E) Sphingomyelin

D) Platelet-activating factor

Which statement about membrane lipids is TRUE? A) Glycerophospholipids are found only in the membranes of plant cells. B) Glycerophospholipids contain fatty acids linked to glycerol through amide bonds. C) Lecithin (phosphatidylcholine), which is used as an emulsifier in margarine and chocolate, is a sphingolipid. D) Some sphingolipids include oligosaccharides in their structure. E) Triacylglycerols are the principal components of erythrocyte membranes.

D) Some sphingolipids include oligosaccharides in their structure.

Advantages to using triacylglycerols, rather than polysaccharaides, to store energy include which reason(s)? A) The carbon atoms of triacylglycerols are more reduced. B) Triacylglycerols contain more oxygen than polysaccharides and therefore are more efficient to oxidize. C) Since triacylglycerols are hydrophobic, excess water does not need to be stored along with them. D) The carbon atoms of triacylglycerols are more reduced, and since triacylglycerols are hydrophobic, excess water does not need to be stored along with them. E) Triacylglycerols contain more oxygen than polysaccharides and therefore are more efficient to oxidize, and since triacylglycerols are hydrophobic, excess water does not need to be stored along with them.

D) The carbon atoms of triacylglycerols are more reduced, and since triacylglycerols are hydrophobic, excess water does not need to be stored along with them.

Which drug is NOT lipid based? A) prednisone B) warfarin C) erythromycin D) aspirin E) lovastatin

D) aspirin

Triacylglycerols are composed of: A) a glycerol backbone. B) three fatty acids. C) amide linkages between the fatty acids and the glycerol. D) both a glycerol backbone and three fatty acids. E) a glycerol backbone, three fatty acids, and amide linkages between the fatty acids and the glycerol.

D) both a glycerol backbone and three fatty acids.

A patient you are treating appears to be deficient in vitamin D. You have previously prescribed vitamin D supplements, but they do not appear to be working. Which organs and/or tissues should you check to make sure that the enzymes they produce are functioning appropriately? A) the liver B) the kidneys C) the pancreas D) both a the liver and the kidneys E) the liver, the kidneys, and the pancreas

D) both a the liver and the kidneys

Nonsteroidal antiinflammatory drugs (NSAIDs) inhibit the synthesis of which signaling lipids from arachidonic acid? A) prostaglandins B) thromboxanes C) leukotrienes D) both prostaglandins and thromboxanes E) both thromboxanes and leukotrienes

D) both prostaglandins and thromboxanes

Which technique separates lipids based on their affinity for a silica gel material? A) thin-layer chromatography B) adsorption chromatography C) mass spectrometry D) both thin-layer and absorption chromatography E) both thin-layer chromatography and mass spectrometry

D) both thin-layer and absorption chromatography

Which technique used to analyze lipids is the fastest but may not be the most accurate? A) thin-layer chromatography B) high-performance chromatography C) nuclear magnetic resonance D) direct mass spectrometry E) gas chromatography

D) direct mass spectrometry

Which health effect is NOT associated with consumption of trans fats? A) lowering of HDL cholesterol B) increased inflammatory response in the body C) raising of LDL cholesterol D) increased joint flexibility due to additional membrane fluidity E) increased risk of heart disease

D) increased joint flexibility due to additional membrane fluidity

Phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to form which signaling molecule that triggers Ca2+ release from the endoplasmic reticulum? A) diacylglycerolphosphate (DAGP) B) inositol 5-monophosphate (IP1) C) diacylglycerol (DAG) D) inositol 1,4,5-triphosphate (IP3) E) inositol 4,5-bisphosphate (IP2)

D) inositol 1,4,5-triphosphate (IP3)

Which types of lipids would NOT have their fatty acids completely hydrolyzed by treatment with acid or alkali? A) triacylglycerols B) galactolipids C) sphingomyelins D) plasmalogens E) phosphatidylcholines

D) plasmalogens

If a patient you are treating has asthmatic attacks due to the overproduction of leukotrienes, which drug would you prescribe to help treat that condition? A) testosterone B) ibuprofen C) aspirin D) prednisone E) warfarin

D) prednisone

Specific hydrolysis of phosphatidylcholine can be achieved by which technique? A) treatment of the lipid with phospholipase C B) treatment of the lipid with mild acid C) dissolving the lipid in chloroform D) treatment of the lipid with both phospholipase C and mild acid E) both treatment of the lipid with phospholipase C and dissolving the lipid in chloroform

D) treatment of the lipid with both phospholipase C and mild acid

Which molecules or substances contain, or are derived from, fatty acids? A) beeswax B) prostaglandins C) sphingolipids D) triacylglycerols E) All of these contain or are derived from fatty acids.

E) All of these contain or are derived from fatty acids.

Humans make which omega-3 polyunsaturated fatty acid from alpha-linolenic acid (ALA)? A) eicosapentaenoic acid (EPA) B) arachidonic acid (ARA) C) docosahexaenoic acid (DHA) D) both eicosapentaenoic acid (EPA) and arachidonic acid (ARA) E) both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

E) both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

Which phospholipid head group is positively charged at pH 7? A) serine B) ethanolamine C) choline D) both serine and ethanolamine E) both ethanolamine and choline

E) both ethanolamine and choline

When a tissue sample is homogenized in a extractant composed of chloroform, methanol, and water, followed by addition of more water to separate the liquid phases, which molecules will remain in the methanol/water phase? A) lipids B) proteins C) sugars D) both lipids and proteins E) both proteins and sugars

E) both proteins and sugars

Which compound is NOT a glycerophospholipid? A) phosphatidylcholine B) phosphatidylethanolamine C) phosphatidylserine D) cardiolipin E) ceramide

E) ceramide

Identify the molecule(s) derived from sterols. A) arachidonic acid B) gangliosides C) phosphatidylglycerol D) prostaglandins E) cortisol

E) cortisol

Overproduction of which types of signaling lipids causes asthmatic attacks? A) prostaglandins B) thromboxanes C) arachidonates D) lipoxins E) leukotrienes

E) leukotrienes

Which lipid compound is NOT at least partially made from the condensation of isoprene units? A) sterols B) limonene C) beta-carotene D) vitamin E E) phosphatidylinositol

E) phosphatidylinositol

Which compound is NOT a type of membrane lipid? A) sphingolipid B) glycerophospholipid C) sulfolipid D) sterol E) triacylglycerolipid

E) triacylglycerolipid

Which statement is TRUE of lipids?

Most are simply polymers of isoprene.

Which statement is NOT true?

Phospholipase B1 hydrolyzes the fatty acid from the 2-position on the glycerol backbone.

_____ contain(s) an ether-linked alkyl group.

Platelet-activating factor

Which statement about membrane lipids is TRUE?

Some sphingolipids include oligosaccharides in their structure.

Which statement is NOT true of sterols?

Sterols are commonly found in bacterial membranes.

Which term BEST describes the cholesterol molecule?

amphipathic

Sphingosine is NOT a component of:

cardiolipin

Which compound is NOT a glycerophospholipid?

ceramide

Fatty acids are a component of:

cerebrosides

Identify the molecule(s) derived from sterols.

cortisol

Biological waxes are all:

esters of single fatty acids with long-chain alcohols

A compound containing N-acetylneuraminic acid (sialic acid) is:

ganglioside GM2.

Tay-Sachs disease is the result of a genetic defect in the metabolism of:

gangliosides.

Which factor is NOT a consequence of partial hydrogenation of vegetable oils?

lower melting temperature

An example of a glycerophospholipid that is involved in cell signaling is:

phosphatidylinositol.

Nonsteroidal anti-inflammatory drugs (NSAIDS) like aspirin and ibuprofen act by blocking production of:

prostaglandins

Which technique is NOT commonly used to analyze lipid composition?

x-ray crystallography