Question 1

Which technique would you NOT use to separate and/or analyze lipids in a laboratory?

Accepted Answer

A)  gel electrophoresis 
B)  thin-layer chromatography 
C)  adsorption chromatography 
D)  mass spectrometry 
E)  high-performance liquid chromatography (HPL
C)  
A)  gel electrophoresis 
B)  thin-layer chromatography 
C)  adsorption chromatography 
D)  mass spectrometry 
E)  high-performance liquid chromatography (HPL
C)

Question 2

Which statement about membrane lipids is TRUE?

Accepted Answer

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. 
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.

Question 3

You are working in a lab studying a bacterial organism, but you are continually having problems with contamination from fungal growth. What might you add to your growth media to address this contamination issue and why?

Accepted Answer

To address the issue of fungal contamina

Question 4

Show the structure of isoprene; explain what is meant by isoprenoid compounds and give an example.

Accepted Answer

Isoprene is a naturally occurring organi

Question 5

Which eicosanoids contains a five-carbon ring as part of its structure?

Accepted Answer

A)  thromboxanes 
B)  prostaglandins 
C)  lipoxins 
D)  leukotrienes 
E)  arachidonates 
A)  thromboxanes 
B)  prostaglandins 
C)  lipoxins 
D)  leukotrienes 
E)  arachidonates

Question 6

Which technique separates lipids based on their affinity for a silica gel material?

Accepted Answer

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 
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

Question 7

Phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to form which signaling molecule that triggers Ca2+ release from the endoplasmic reticulum?

Accepted Answer

A)  diacylglycerolphosphate (DAGP) 
B)  inositol 5-monophosphate (IP1) 
C)  diacylglycerol (DAG) 
D)  inositol 1,4,5-triphosphate (IP3) 
E)  inositol 4,5-bisphosphate (IP2) 
A)  diacylglycerolphosphate (DAGP) 
B)  inositol 5-monophosphate (IP1) 
C)  diacylglycerol (DAG) 
D)  inositol 1,4,5-triphosphate (IP3) 
E)  inositol 4,5-bisphosphate (IP2)

Question 8

In high-performance liquid chromatography of lipid mixtures using a column packed with a silica gel, which types of lipids will elute first?

Accepted Answer

A)  positively charged lipids 
B)  neutral lipids 
C)  negatively charged lipids 
D)  polar lipids 
E)  zwitterionic lipids 
A)  positively charged lipids 
B)  neutral lipids 
C)  negatively charged lipids 
D)  polar lipids 
E)  zwitterionic lipids

Question 9

Specific hydrolysis of phosphatidylcholine can be achieved by which technique?

Accepted Answer

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 
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

Question 10

Which type of chemical linkage is used to join fatty acids to glycerol?

Accepted Answer

A)  an ether linkage 
B)  a peptide bond 
C)  an ester linkage 
D)  a double bond 
E)  a peroxide bond 
A)  an ether linkage 
B)  a peptide bond 
C)  an ester linkage 
D)  a double bond 
E)  a peroxide bond

Question 11

Which statement about sterols is TRUE?

Accepted Answer

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. 
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.

Question 12

Describe the differences between the glycosphingolipids corresponding to the A, B, and O human blood group antigens.

Accepted Answer

The A blood group antigen is characteriz

Question 13

Advantages to using triacylglycerols, rather than polysaccharaides, to store energy include which reason(s)?

Accepted Answer

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. 
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.

Question 14

Which molecule is MOST commonly used as a backbone the linkage of three fatty acids to form fats?

Accepted Answer

A)  glycogen 
B)  glycerol 
C)  sphingosine 
D)  glucose 
E)  phosphoglycerol 
A)  glycogen 
B)  glycerol 
C)  sphingosine 
D)  glucose 
E)  phosphoglycerol

Question 15

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

Accepted Answer

A)  arachidonic acid. 
B)  ceramide. 
C)  phosphatidylinositol. 
D)  testosterone. 
E)  vitamin A (retinol). 
A)  arachidonic acid. 
B)  ceramide. 
C)  phosphatidylinositol. 
D)  testosterone. 
E)  vitamin A (retinol).

Question 16

Which statement BEST describes how the volatility of lipids is increased for analysis by gas chromatography?

Accepted Answer

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. 
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.

Question 17

Show the basic structure of all glycerophospholipids.

Accepted Answer

Glycerophospholipids, also known as phos

Question 18

Which statement concerning fatty acids is CORRECT?

Accepted Answer

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. 
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.

Question 19

Which types of lipids would NOT have their fatty acids completely hydrolyzed by treatment with acid or alkali?

Accepted Answer

A)  triacylglycerols 
B)  galactolipids 
C)  sphingomyelins 
D)  plasmalogens 
E)  phosphatidylcholines 
A)  triacylglycerols 
B)  galactolipids 
C)  sphingomyelins 
D)  plasmalogens 
E)  phosphatidylcholines

Question 20

Which types of membrane lipids are modified to determine blood type in humans?

Accepted Answer

A)  phosphatidylserines 
B)  glycosphingolipids 
C)  galactolipids 
D)  plasmalogens 
E)  sphingomyelins 
A)  phosphatidylserines 
B)  glycosphingolipids 
C)  galactolipids 
D)  plasmalogens 
E)  sphingomyelins

Exam 10: Lipids

Which technique would you NOT use to separate and/or analyze lipids in a laboratory?

Which statement about membrane lipids is TRUE?

You are working in a lab studying a bacterial organism, but you are continually having problems with contamination from fungal growth. What might you add to your growth media to address this contamination issue and why?

Show the structure of isoprene; explain what is meant by isoprenoid compounds and give an example.

Which eicosanoids contains a five-carbon ring as part of its structure?

Which technique separates lipids based on their affinity for a silica gel material?

Phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to form which signaling molecule that triggers Ca2+ release from the endoplasmic reticulum?

In high-performance liquid chromatography of lipid mixtures using a column packed with a silica gel, which types of lipids will elute first?

Specific hydrolysis of phosphatidylcholine can be achieved by which technique?

Which type of chemical linkage is used to join fatty acids to glycerol?

Which statement about sterols is TRUE?

Describe the differences between the glycosphingolipids corresponding to the A, B, and O human blood group antigens.

Advantages to using triacylglycerols, rather than polysaccharaides, to store energy include which reason(s)?

Which molecule is MOST commonly used as a backbone the linkage of three fatty acids to form fats?

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

Which statement BEST describes how the volatility of lipids is increased for analysis by gas chromatography?

Show the basic structure of all glycerophospholipids.

Which statement concerning fatty acids is CORRECT?

Which types of lipids would NOT have their fatty acids completely hydrolyzed by treatment with acid or alkali?

Which types of membrane lipids are modified to determine blood type in humans?

The Foundations of Biochemistry

Water

Amino Acids, Peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Enzymes

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

DNA-Based Information Technologies

Biological Membranes and Transport

Biosignaling

Bioenergetics and Biochemical Reaction Types

Glycolysis, Gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, Nucleotides, and Related Molecules

Hormonal Regulation and Integration of Mammalian Metabolism

Genes and Chromosomes

DNA Metabolism

RNA Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

Phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP₂) to form which signaling molecule that triggers Ca²⁺ release from the endoplasmic reticulum?