Question 1

The membrane-spanning portion of a transmembrane protein is almost always a β-strand.

Accepted Answer

A) True 
 B)False

Question 2

Margarines made from plant oils are healthier, since they are hydrogenated for spreadability.

Accepted Answer

A) True 
 B)False

Question 3

Which statement is false about lipid rafts?

Accepted Answer

A)  Membrane proteins help maintain the integrity of membrane rafts. 
B)  They are distributed non-uniformly on the mammal cell surfaces. 
C)  They occur mostly on the outer mitochondrial membrane. 
D)  They are patches of cholesterol associated with sphingolipids. 
A)  Membrane proteins help maintain the integrity of membrane rafts. 
B)  They are distributed non-uniformly on the mammal cell surfaces. 
C)  They occur mostly on the outer mitochondrial membrane. 
D)  They are patches of cholesterol associated with sphingolipids.

Question 4

Which statement is not true about G proteins?

Accepted Answer

A)  They are integral membrane proteins. 
B)  They are multisubunit proteins consisting of α, β and γ subunits. 
C)  They are slowly inactivated by their own GTPase activity. 
D)  They act as transducers for hormones. 
A)  They are integral membrane proteins. 
B)  They are multisubunit proteins consisting of α, β and γ subunits. 
C)  They are slowly inactivated by their own GTPase activity. 
D)  They act as transducers for hormones.

Question 5

Match each technique with its purpose." A) separate groups of neutrallipids
B) diacylglycerolseparation based on chain length and degree of unsaturation
C) Lateral movement of proteins in cell membranes
D) Separate fatty acid esters
E) Separate neutrallipids and phospholipids
-cell fusion

Accepted Answer

The answer of Match each technique with its purpose." A)...

Question 6

Tay-Sachs disease results from

Accepted Answer

A)  a deficiency of GM2. 
B)  defective lysosomes. 
C)  malfunction of cerebroside metabolism. 
D)  the accumulation of GM2. 
A)  a deficiency of GM2. 
B)  defective lysosomes. 
C)  malfunction of cerebroside metabolism. 
D)  the accumulation of GM2.

Question 7

The constant Ktr is the concentration of the molecule being transported at which the transport protein is half-saturated.

Accepted Answer

A) True 
 B)False

Question 8

Isoprenoids are lipids which neither contain nor are derived from fatty acids and include

Accepted Answer

A)  steroids. 
B)  waxes. 
C)  terpenes. 
D)  A and C only 
E)  A, B, and C 
A)  steroids. 
B)  waxes. 
C)  terpenes. 
D)  A and C only 
E)  A, B, and C

Question 9

Bactoprenol synthesis is inhibited by the antibiotic bacitracin. Therefore, it can be used to treat yeast infections.

Accepted Answer

A) True 
 B)False

Question 10

Match each lipid with the appropriate function. A) constricts blood vessels
B) synthesis of bacterial cell wall
C) smooth muscle contraction
D) leaf coatings
E) blood clotting
-leukotriene D4

Accepted Answer

Question 11

Determination of the tertiary structure of a membrane protein finds that the outer surface is composed primarily of hydrophobic residues. Which conclusion is most likely from this observation?

Accepted Answer

A)  It is a lipid-anchored membrane protein. 
B)  It is an integral protein. 
C)  The protein must be involved in passive transport. 
D)  The protein can undergo transverse diffusion. 
A)  It is a lipid-anchored membrane protein. 
B)  It is an integral protein. 
C)  The protein must be involved in passive transport. 
D)  The protein can undergo transverse diffusion.

Question 12

Like plasmologens, sphingolipids are found in relative abundance in

Accepted Answer

A)  bacteria. 
B)  plant cells. 
C)  nerve cells. 
D)  intestinal cells. 
E)  All of the above 
A)  bacteria. 
B)  plant cells. 
C)  nerve cells. 
D)  intestinal cells. 
E)  All of the above

Question 13

Match each lipid with the appropriate function. A) constricts blood vessels
B) synthesis of bacterial cell wall
C) smooth muscle contraction
D) leaf coatings
E) blood clotting
-wax

Accepted Answer

The answer of Match each lipid with the appropriate function....

Question 14

A fatty acid designated w-3

Accepted Answer

A)  has three double bonds. 
B)  is saturated. 
C)  has a double bond three carbons from the end of the chain. 
D)  has a double bond three carbons from the a-carbon. 
A)  has three double bonds. 
B)  is saturated. 
C)  has a double bond three carbons from the end of the chain. 
D)  has a double bond three carbons from the a-carbon.

Question 15

Triacylglycerols are not found in cell membranes because they are

Accepted Answer

A)  amphipathic. 
B)  not amphipathic. 
C)  not abundant in cells. 
D)  charged at biological pH. 
A)  amphipathic. 
B)  not amphipathic. 
C)  not abundant in cells. 
D)  charged at biological pH.

Question 16

A deficiency in the synthesis of sphingomyelins or cerebrosides will most likely result in the improper formation of

Accepted Answer

A)  cell surfaces. 
B)  cell to cell communication. 
C)  nerve cells. 
D)  blood groups. 
E)  All of the above 
A)  cell surfaces. 
B)  cell to cell communication. 
C)  nerve cells. 
D)  blood groups. 
E)  All of the above

Question 17

If the concentration of a solute is the same both inside and outside the cell, what might you expect with regard to its transport by a membrane protein?

Accepted Answer

A)  Since there is no concentration gradient, no transport either in or out of the cell is possible. 
B)  Movement of the solute across the membrane could occur and cause accumulated on one side of the membrane by an active transport protein. 
C)  The transport protein has been saturated. 
D)  The solute must be phosphorylated with a phosphate group from ATP before further transport can occur. 
A)  Since there is no concentration gradient, no transport either in or out of the cell is possible. 
B)  Movement of the solute across the membrane could occur and cause accumulated on one side of the membrane by an active transport protein. 
C)  The transport protein has been saturated. 
D)  The solute must be phosphorylated with a phosphate group from ATP before further transport can occur.

Question 18

You have purified a cell membrane and wish to isolate a transport protein from it. Which treatment might you select?

Accepted Answer

A)  Add a detergent. 
B)  Change the ionic strength. 
C)  React with a protease. 
D)  Add phenylisothiocyanate PIT
C) . 
A)  Add a detergent. 
B)  Change the ionic strength. 
C)  React with a protease. 
D)  Add phenylisothiocyanate PIT
C) .

Question 19

Match each technique with its purpose." A) separate groups of neutrallipids
B) diacylglycerolseparation based on chain length and degree of unsaturation
C) Lateral movement of proteins in cell membranes
D) Separate fatty acid esters
E) Separate neutrallipids and phospholipids
-HPLC

Accepted Answer

The answer of Match each technique with its purpose." A)...

Question 20

Dietary triacylglycerols are digested as a result of

Accepted Answer

A)  lipase action. 
B)  bile salts. 
C)  micelle formation. 
D)  diffusion and absorption by intestinal cells. 
E)  All of the above 
A)  lipase action. 
B)  bile salts. 
C)  micelle formation. 
D)  diffusion and absorption by intestinal cells. 
E)  All of the above

Exam 9: Lipids and Membranes

The membrane-spanning portion of a transmembrane protein is almost always a β-strand.

Margarines made from plant oils are healthier, since they are hydrogenated for spreadability.

Which statement is false about lipid rafts?

Which statement is not true about G proteins?

Match each technique with its purpose." A) separate groups of neutrallipids B) diacylglycerolseparation based on chain length and degree of unsaturation C) Lateral movement of proteins in cell membranes D) Separate fatty acid esters E) Separate neutrallipids and phospholipids -cell fusion

Tay-Sachs disease results from

The constant Ktr is the concentration of the molecule being transported at which the transport protein is half-saturated.

Isoprenoids are lipids which neither contain nor are derived from fatty acids and include

Bactoprenol synthesis is inhibited by the antibiotic bacitracin. Therefore, it can be used to treat yeast infections.

Match each lipid with the appropriate function. A) constricts blood vessels B) synthesis of bacterial cell wall C) smooth muscle contraction D) leaf coatings E) blood clotting -leukotriene D4

Determination of the tertiary structure of a membrane protein finds that the outer surface is composed primarily of hydrophobic residues. Which conclusion is most likely from this observation?

Like plasmologens, sphingolipids are found in relative abundance in

Match each lipid with the appropriate function. A) constricts blood vessels B) synthesis of bacterial cell wall C) smooth muscle contraction D) leaf coatings E) blood clotting -wax

A fatty acid designated w-3

Triacylglycerols are not found in cell membranes because they are

A deficiency in the synthesis of sphingomyelins or cerebrosides will most likely result in the improper formation of

If the concentration of a solute is the same both inside and outside the cell, what might you expect with regard to its transport by a membrane protein?

You have purified a cell membrane and wish to isolate a transport protein from it. Which treatment might you select?

Match each technique with its purpose." A) separate groups of neutrallipids B) diacylglycerolseparation based on chain length and degree of unsaturation C) Lateral movement of proteins in cell membranes D) Separate fatty acid esters E) Separate neutrallipids and phospholipids -HPLC

Dietary triacylglycerols are digested as a result of

Introduction to Biochemistry

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Coenzymes and Vitamins

Carbohydrates

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

Dna Replication, Repair, and Recombination

Transcription and Rna Processing

Protein Synthesis

Recombinant Dna Technology

Filters

The constant K_tris the concentration of the molecule being transported at which the transport protein is half-saturated.

Match each lipid with the appropriate function. A) constricts blood vessels B) synthesis of bacterial cell wall C) smooth muscle contraction D) leaf coatings E) blood clotting -leukotriene D₄