Question 1

Considering the characteristics of common fatty acids found in animals described in the text,which of the structures shown below would you consider the most rare fatty acid if found in animals?

Accepted Answer

A) Structure A 
B) Structure B 
C) Structure C 
D) Structure D 
E) All structures would be equally rare.

Question 2

Which of the following amino acids from an integral membrane protein would likely contact the membrane?

Accepted Answer

A) Asn 
B) Gln 
C) Glu 
D) Ala 
E) Asp

Question 3

The biconcave shape of erythrocytes which maximizes rapid diffusion of oxygen is primarily maintained by

Accepted Answer

A) the covalent attachment of organelles within the cell to the membrane. 
B) high levels of rigid cholesterol and saturated lipids that strengthen the membrane. 
C) a network of embedded spectrin that crosslink to other membrane proteins, 
D) a network of tightly-packed anion channel proteins. 
E) a relatively low concentration of integral membrane proteins allowing tighter packing of lipid molecules within the membrane.

Question 4

A researcher is developing a new drug for the treatment of influenza.Based on the information presented in the text about the influenza virus,which of the following drug reactions describes the action of this new drug?

Accepted Answer

A) A drug which specifically interrupts the conformational change that results from the pH change in the endosome. 
B) A drug which enhances the function of a normally quiescent enzyme responsible for cleavage of the carbohydrate component on glycophorin A proteins. 
C) A drug which readily binds the hemagglutinin tag and results in conformational change. 
D) All of the above are potential actions of this new drug. 
E) None of the above is a plausible reaction for this new drug.

Question 5

The protein that forms a transmembrane pore that allows growing polypeptides to pass through the RER membrane is called the ______.

Accepted Answer

A) signal recognition particle 
B) signal peptide 
C) docking protein 
D) translocon 
E) none of the above

Question 6

Identify the compound below:

Accepted Answer

A) a glycerolphospholipid 
B) sphingosine 
C) ceramide 
D) spingomylelin 
E) ganglioside

Question 7

Matching

-A steroid-derived hormone that must be activated by hydroxylation,______ regulates Ca2+ metabolism.

Accepted Answer

A)  amphiphiles 
B)  vitamin D 
C)  arachidonic acid 
D)  phosphatidylethanolamine 
E)  sterol
F) gangliosides
G) phosphatidylcholine
H) glycerophospholipids
I) sphingomyelins
J) cholesterol
K) triacylglycerols
L) plasmalogen
M) nonpolar

Question 8

Which of the following correctly describes the usefulness of SNAREs?
(I)They are essential for proper post-translation processing.
(II)They are a critical element in the function of the secretory pathway.
(III)They are effective at overcoming electrostatic repulsion between vesicle membranes.
(IV)They facilitate anchoring between vesicle membranes.

Accepted Answer

A) I,II,III,IV 
B) II,III 
C) III 
D) IV 
E) III,IV

Question 9

The _________,which is found embedded in the endoplasmic reticulum,is a _______ protein.

Accepted Answer

A) SRP receptor…signal 
B) ribosome…transmembrane pore 
C) translocon…transmembrane pore 
D) translocon…peripheral 
E) ribosome…signal

Question 10

Matching

-A glycerophospholipid in which the C1 substituent linkage forms a vinyl ether that is more easily oxidized than its ester counterpart is called a ______.

Accepted Answer

A)  amphiphiles 
B)  vitamin D 
C)  arachidonic acid 
D)  phosphatidylethanolamine 
E)  sterol
F) gangliosides
G) phosphatidylcholine
H) glycerophospholipids
I) sphingomyelins
J) cholesterol
K) triacylglycerols
L) plasmalogen
M) nonpolar

Question 11

Which of the following statements describes one reason that plant oils are generally healthier for human consumption than animal fats?

Accepted Answer

A) Plant oils usually contain more unsaturated fatty acids than animal fats. 
B) Plant oils usually contain more trans fatty acids than animal fats. 
C) Plant oils usually have a higher degree of saturation than animal fats. 
D) Plant oils are glycerol based rather than phospholipid based. 
E) Plant oils have shorter chain fatty acids than animal fats.

Question 12

I-cell disease results in psychomotor retardation,skeletal deformities and death.Which of the following is true regarding this disease?

Accepted Answer

A) The disease results in inclusion of glycosaminoglycans and glycolipids due the absence of an essential carbohydrate marker that directs the lysosomal hydrolases to the lysosome. 
B) The disease results in inclusion of glycolipids due mutations in the lysosomal hydrolases that render them inactive. 
C) The disease results in increased expression of SNARE proteins that result in vesicle fusion and exchange of glycosaminoglycans. 
D) The disease results from the lack of KDEL sequences which would normally signal their return to the ER following Golgi processing. 
E) All of the above are true.

Question 13

Transmembrane proteins
(I)are predominantly constructed of a single hydrophobic α-helix.
(II)are often constructed from bundles of hydrophobic $\alpha$-helices.
(III)are sometimes constructed from β-barrels with hydrophobic interiors and exteriors.
(IV)may have transmembrane helices identified by the free energy of transfer to water.

Accepted Answer

A) I,III,IV 
B) II,III 
C) II,III,IV 
D) I,IV 
E) II,IV

Question 14

Matching

-The myelin sheath contains high levels of ______.

Accepted Answer

A)  amphiphiles 
B)  vitamin D 
C)  arachidonic acid 
D)  phosphatidylethanolamine 
E)  sterol
F) gangliosides
G) phosphatidylcholine
H) glycerophospholipids
I) sphingomyelins
J) cholesterol
K) triacylglycerols
L) plasmalogen
M) nonpolar

Question 15

Which experiment listed below did NOT verify the fluid mosaic model of membranes?

Accepted Answer

A) observation of lateral movement of membrane across the cell while anchored to a microscope slide. 
B) monitoring the transverse diffusion of human proteins within a mouse cell membrane. 
C) membrane fusion between mouse and human cells. 
D) monitoring the lateral diffusion of fluorphores both bleached and unbleached. 
E) All of the above describe experiments that verified the fluid mosaic model of membranes.

Question 16

Cholesterol

Accepted Answer

A) incorporation into the membrane results in increased rigidity. 
B) functions as a precursor to cerebrosides. 
C) is synthesized in two-carbon units. 
D) is synthesized from steroid hormones. 
E) all of the above

Question 17

Which of the following structures correctly represents a glycerophospholipid?

Accepted Answer

A) Structure A 
B) Structure B 
C) Structure C 
D) Structure D 
E) None of the above

Question 18

While fatty acids are most often formed by the condensation of __-carbon units,isoprenoids are assembled from __-carbon units.

Accepted Answer

A) 5,3 
B) 4,2 
C) 2,3 
D) 2,5 
E) 3,4

Question 19

In bacteria,phospholipids are synthesized:

Accepted Answer

A) on the cytoplasmic face of cell membranes 
B) at the rough endoplasmic reticulum 
C) on the extracellular face of the cell membrane 
D) on site at the endoplasmic reticulum. 
E) nonenzymatically at the site of the membrane.

Question 20

Which of the following is (are)NOT found as covalently attached anchors in lipid-linked proteins?

Accepted Answer

A) isoprenoid groups 
B) fatty acids 
C) cholesterol and other sterols 
D) glycosylphosphatidyl inositol groups 
E) All of the above are found as covalently attached anchors in lipid-linked proteins.

Exam 9: Lipids and Biological Membranes

Considering the characteristics of common fatty acids found in animals described in the text,which of the structures shown below would you consider the most rare fatty acid if found in animals?

Which of the following amino acids from an integral membrane protein would likely contact the membrane?

The biconcave shape of erythrocytes which maximizes rapid diffusion of oxygen is primarily maintained by

A researcher is developing a new drug for the treatment of influenza.Based on the information presented in the text about the influenza virus,which of the following drug reactions describes the action of this new drug?

The protein that forms a transmembrane pore that allows growing polypeptides to pass through the RER membrane is called the ______.

Identify the compound below:

Matching -A steroid-derived hormone that must be activated by hydroxylation,______ regulates Ca²⁺ metabolism.

The ___,which is found embedded in the endoplasmic reticulum,is a _ protein.

Matching -A glycerophospholipid in which the C1 substituent linkage forms a vinyl ether that is more easily oxidized than its ester counterpart is called a ______.

Which of the following statements describes one reason that plant oils are generally healthier for human consumption than animal fats?

I-cell disease results in psychomotor retardation,skeletal deformities and death.Which of the following is true regarding this disease?

Matching -The myelin sheath contains high levels of ______.

Which experiment listed below did NOT verify the fluid mosaic model of membranes?

Cholesterol

Which of the following structures correctly represents a glycerophospholipid?

While fatty acids are most often formed by the condensation of -carbon units,isoprenoids are assembled from -carbon units.

In bacteria,phospholipids are synthesized:

Which of the following is (are) NOT found as covalently attached anchors in lipid-linked proteins?