Question 1

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 2

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 3

Sphingolipids
I.contain a glycerol core with a phosphocholine headgroup.
II.contain a modified sphingosine.
III.often function as receptor components of membranes.
IV.function as a precursor to sterols.

Accepted Answer

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

Question 4

Which of the following classes of proteins associates with the membrane bilayer with the lowest energy and would therefore be most difficult to separate from the membrane?

Accepted Answer

A) extrinsic proteins 
B) lipid-linked proteins 
C) transmembrane proteins 
D) peripheral proteins 
E) hydrophilic proteins

Question 5

Adipocytes

Accepted Answer

A) are specialized cells for the synthesis of triglycerides. 
B) are specialized cells for short term energy storage. 
C) provide compartments for efficient membrane bilayer synthesis. 
D) exist primarily in a thin layer surrounding major muscle groups as a rapid high energy source. 
E) All of the above characterize adipocytes.

Question 6

Lung surfactants function to decrease the likelihood of collapse of the alveoli when air is expired.Based on your knowledge of lipids and amphipathic molecules, which of the following explains the mechanism by which the dipalmitoyl phosphatidylcholine (DPPC)can accomplish this task?

Accepted Answer

A) The hydrophilic head groups are bulky and expand the surface area of the alveoli. 
B) The inclusion of saturated fatty acids on the glycerophospholipid allows close packing of tail groups which are fully extended and prevent collapse upon expiration. 
C) The hydrophobic portion of the DPPC repel air, forcing the alveoli space open. 
D) The choline portion of the molecule is bulky, thus increasing surface area of alveoli. 
E) None of the above explain the mechanism.

Question 7

Matching
-Eicosanoids are 20-carbon compounds derived from ______.

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

The signal peptide sequence
I.is often used to direct proteins to the lysosome for incorporation into the lysosome.
II.is usually not used for small eukaryotic proteins.
III.of some transmembrane proteins is embedded into the membrane as an anchor.
IV.is usually cleaved off the completed protein.

Accepted Answer

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

Question 9

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 10

Matching
-A derivative of______ is the major lipid in lung surfactant.

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

The _________ model describes the cell membrane as an assortment of integral proteins suspended freely in a lipid bilayer.

Accepted Answer

A) FRAP 
B) cellular fusion 
C) transverse diffusion 
D) lateral diffusion 
E) fluid mosaic

Question 12

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 13

Rank the melting points of the following fatty acids from highest to lowest: 
(1)cis-oleic(18:1)
(2)trans-oleic (18:1)
(3)linoleic (18:2) 
(4)steraic (18:0)
(5)palmitic (16:0)

Accepted Answer

A) 1 > 2 > 3 > 5 > 4 
B) 4 > 5 > 2 > 1 > 3 
C) 4 > 5 > 3 > 2 > 1 
D) 5 > 4 > 2 > 1 > 3 
E) none of the above

Question 14

Transmembrane proteins
I.are predominantly constructed of a single hydrophobic α-helix.
II.are often constructed from bundles of hydrophobic $\beta$-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 15

Which of the following points to the correct location of attachment for a fatty acid which would yield a ceramide?

Accepted Answer

A) Location A 
B) Location B 
C) Location C 
D) Location B or C 
E) The correct location is not shown

Question 16

A researcher has designed a new drug that will block the release of certain neurotransmitters from the synaptic cleft.Which of the following reactions must be blocked by this new drug?

Accepted Answer

A) The drug binds the receptors in the postsynaptic membrane and blocks neurotransmitter binding. 
B) The drug binds the presynaptic membrane greatly facilitating the rate of transverse diffusion, thus changing the composition of the membrane. 
C) The drug enhances activity of SNARE proteins, thus facilitating fusion. 
D) All of the above are plausible actions of this new drug. 
E) None of the above is a plausible action of this new drug.

Question 17

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 18

Triglycerides contain more metabolic energy per unit weight than glycogen because:
I.Glycogen has greater polarity than fatty acids.
II.Fatty acids predominate in an anhydrous form
III.Fatty acids are less oxidized than carbohydrates.
IV.Triglycerides have a higher average molecular mass.

Accepted Answer

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

Question 19

Which of the structures below is an example of an $\omega$-3 polyunsaturated fatty acid?

Accepted Answer

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

Question 20

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

Exam 9: Lipids and Biological Membranes

Which of the following structures correctly represents a glycerophospholipid?

Sphingolipids I.contain a glycerol core with a phosphocholine headgroup. II.contain a modified sphingosine. III.often function as receptor components of membranes. IV.function as a precursor to sterols.

Which of the following classes of proteins associates with the membrane bilayer with the lowest energy and would therefore be most difficult to separate from the membrane?

Adipocytes

Lung surfactants function to decrease the likelihood of collapse of the alveoli when air is expired.Based on your knowledge of lipids and amphipathic molecules, which of the following explains the mechanism by which the dipalmitoyl phosphatidylcholine (DPPC) can accomplish this task?

Matching -Eicosanoids are 20-carbon compounds derived from ______.

The signal peptide sequence I.is often used to direct proteins to the lysosome for incorporation into the lysosome. II.is usually not used for small eukaryotic proteins. III.of some transmembrane proteins is embedded into the membrane as an anchor. IV.is usually cleaved off the completed protein.

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?

Matching -A derivative of______ is the major lipid in lung surfactant.

The _________ model describes the cell membrane as an assortment of integral proteins suspended freely in a lipid bilayer.

In bacteria, phospholipids are synthesized:

Rank the melting points of the following fatty acids from highest to lowest: (1) cis-oleic(18:1) (2) trans-oleic (18:1) (3) linoleic (18:2) (4) steraic (18:0) (5) palmitic (16:0)

Which of the following points to the correct location of attachment for a fatty acid which would yield a ceramide?

A researcher has designed a new drug that will block the release of certain neurotransmitters from the synaptic cleft.Which of the following reactions must be blocked by this new drug?

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

Triglycerides contain more metabolic energy per unit weight than glycogen because: I.Glycogen has greater polarity than fatty acids. II.Fatty acids predominate in an anhydrous form III.Fatty acids are less oxidized than carbohydrates. IV.Triglycerides have a higher average molecular mass.

Which of the structures below is an example of an $\omega$ -3 polyunsaturated fatty acid? $Which of the structures below is an example of an \omega -3 polyunsaturated fatty acid? A) Structure A B) Structure B C) Structure C D) Structure D E) None of the above$

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

Exam 9: Lipids and Biological Membranes

Which of the following structures correctly represents a glycerophospholipid?

Sphingolipids I.contain a glycerol core with a phosphocholine headgroup. II.contain a modified sphingosine. III.often function as receptor components of membranes. IV.function as a precursor to sterols.

Which of the following classes of proteins associates with the membrane bilayer with the lowest energy and would therefore be most difficult to separate from the membrane?

Adipocytes

Lung surfactants function to decrease the likelihood of collapse of the alveoli when air is expired.Based on your knowledge of lipids and amphipathic molecules, which of the following explains the mechanism by which the dipalmitoyl phosphatidylcholine (DPPC) can accomplish this task?

Matching -Eicosanoids are 20-carbon compounds derived from ______.

The signal peptide sequence I.is often used to direct proteins to the lysosome for incorporation into the lysosome. II.is usually not used for small eukaryotic proteins. III.of some transmembrane proteins is embedded into the membrane as an anchor. IV.is usually cleaved off the completed protein.

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?

Matching -A derivative of______ is the major lipid in lung surfactant.

The _________ model describes the cell membrane as an assortment of integral proteins suspended freely in a lipid bilayer.

In bacteria, phospholipids are synthesized:

Rank the melting points of the following fatty acids from highest to lowest: (1) cis-oleic(18:1) (2) trans-oleic (18:1) (3) linoleic (18:2) (4) steraic (18:0) (5) palmitic (16:0)

Which of the following points to the correct location of attachment for a fatty acid which would yield a ceramide?

A researcher has designed a new drug that will block the release of certain neurotransmitters from the synaptic cleft.Which of the following reactions must be blocked by this new drug?

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

Triglycerides contain more metabolic energy per unit weight than glycogen because: I.Glycogen has greater polarity than fatty acids. II.Fatty acids predominate in an anhydrous form III.Fatty acids are less oxidized than carbohydrates. IV.Triglycerides have a higher average molecular mass.

Which of the structures below is an example of an ω\omegaω -3 polyunsaturated fatty acid?

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

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

Which of the structures below is an example of an $\omega$ -3 polyunsaturated fatty acid? $Which of the structures below is an example of an \omega -3 polyunsaturated fatty acid? A) Structure A B) Structure B C) Structure C D) Structure D E) None of the above$

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