Question 1

Transport of glucose from the intestine into the intestinal cells is accomplished by a(n) ________. This is an example of ___________.

Accepted Answer

A)  uniporter; passive transport 
B)  uniporter; primary active transport 
C)  symporter; primary active transport 
D)  symporter; secondary active transport 
E)  antiporter; secondary active transport 
A)  uniporter; passive transport 
B)  uniporter; primary active transport 
C)  symporter; primary active transport 
D)  symporter; secondary active transport 
E)  antiporter; secondary active transport D

Question 2

At the neuromuscular synapse, acetylcholine is stored in vesicles in the ___ while acetylcholine receptors are found on the ___.

Accepted Answer

nerve cell, muscle cell

Question 3

Which type of ion channel is blocked by lidocaine, a local anesthetic?

Accepted Answer

A)  K+ 
B)  Na+ 
C)  pre-synaptic Ca2+ 
D)  post-synaptic Ca2+ 
E)  none of the above 
A)  K+ 
B)  Na+ 
C)  pre-synaptic Ca2+ 
D)  post-synaptic Ca2+ 
E)  none of the above B

Question 4

Which of the following statements regarding membrane transporters is true?

Accepted Answer

A)  a porin is always open but only transports solutes in one direction 
B)  an ion channel selective for K+ will also allow Na+ through since both are small enough to fit through the channel 
C)  amphotericin is able to assemble inside a membrane in such a manner to form a channel through which K+ and Na+ flow, thus disrupting the ion gradient 
D)  K+ channels can work in both directions, allowing the neuronal action potential to move in multiple directions 
E)  none of the above 
A)  a porin is always open but only transports solutes in one direction 
B)  an ion channel selective for K+ will also allow Na+ through since both are small enough to fit through the channel 
C)  amphotericin is able to assemble inside a membrane in such a manner to form a channel through which K+ and Na+ flow, thus disrupting the ion gradient 
D)  K+ channels can work in both directions, allowing the neuronal action potential to move in multiple directions 
E)  none of the above

Question 5

Which of the following occurs during the fusion of a synaptic vesicle and cell membrane?

Accepted Answer

A)  SNARE complexes dissociate to allow membrane fusion to occur 
B)  addition of triacylglycerols to the membrane allows the bilayer to bow inward 
C)  selective removal of acyl chains from membrane phospholipids allows the bilayer to bow outward 
D)  the composition of the two membranes has no effect upon the rate of fusion 
E)  none of the above 
A)  SNARE complexes dissociate to allow membrane fusion to occur 
B)  addition of triacylglycerols to the membrane allows the bilayer to bow inward 
C)  selective removal of acyl chains from membrane phospholipids allows the bilayer to bow outward 
D)  the composition of the two membranes has no effect upon the rate of fusion 
E)  none of the above

Question 6

Pinocytosis is a specific type of exocytosis where small amounts of intracellular material are sequestered in a vesicle followed by membrane fusion and transport of the material to the outside of the cell.

Accepted Answer

A) True 
 B)False

Question 7

Which of the following will cause the opening or closing of a gated ion channel?

Accepted Answer

A)  pH change 
B)  phosphorylation 
C)  voltage change 
D)  ligand binding 
E)  all of the above 
A)  pH change 
B)  phosphorylation 
C)  voltage change 
D)  ligand binding 
E)  all of the above

Question 8

The P-glycoprotein is an example of a(n) _____ which has been linked to drug resistance in the treatment of _____.

Accepted Answer

A)  ABC transporter; bacterial infections 
B)  ABC transporter; cancer 
C)  Na,K-ATPase; viral infections 
D)  Na,K-ATPase; parasitic infections 
E)  none of the above 
A)  ABC transporter; bacterial infections 
B)  ABC transporter; cancer 
C)  Na,K-ATPase; viral infections 
D)  Na,K-ATPase; parasitic infections 
E)  none of the above

Question 9

Which of the following is true regarding SNARE complex formation?

Accepted Answer

A)  prior to membrane association, SNARE proteins are in an unfolded state 
B)  two proteins of the SNARE complex come from the membrane and one from the synaptic vesicle 
C)  formation of a four-helix complex is critical for membrane association of the vesicle 
D)  formation of the SNARE complex is thermodynamically favorable, as is membrane fusion 
E)  all of the above 
A)  prior to membrane association, SNARE proteins are in an unfolded state 
B)  two proteins of the SNARE complex come from the membrane and one from the synaptic vesicle 
C)  formation of a four-helix complex is critical for membrane association of the vesicle 
D)  formation of the SNARE complex is thermodynamically favorable, as is membrane fusion 
E)  all of the above

Question 10

Exosomes often contain ___ And ___

Accepted Answer

The answer of Exosomes often contain ___ And ___...

Question 11

During receptor-mediated endocytosis, the movement of the receptor-ligand complex requires the presence of ___ that functions by mediating ___.

Accepted Answer

coat proteins, pinch

Question 12

Which of the following is true regarding the glucose transporter?

Accepted Answer

A)  in addition to glucose, it will transport any other monosaccharide with six carbons 
B)  binding of glucose causes a conformational change so that the transporter is never open on both sides of the membrane 
C)  ATP hydrolysis prevents the transporter from working in reverse 
D)  it is able to transport glucose into a cell against a concentration gradient 
E)  none of the above 
A)  in addition to glucose, it will transport any other monosaccharide with six carbons 
B)  binding of glucose causes a conformational change so that the transporter is never open on both sides of the membrane 
C)  ATP hydrolysis prevents the transporter from working in reverse 
D)  it is able to transport glucose into a cell against a concentration gradient 
E)  none of the above

Question 13

Which of the following would be the first to occur following opening of Ca2+ channels during acetylcholine-mediated neurotransmission to a muscle cell?

Accepted Answer

A)  binding of SNARE complex to synaptic vesicles and pre-synaptic membrane 
B)  binding of acetylcholine to muscle cell receptors 
C)  reuptake of acetylcholine by the nerve cell 
D)  hydrolysis of acetylcholine by acetylcholinesterase 
E)  release of acetylcholine by the nerve cell 
A)  binding of SNARE complex to synaptic vesicles and pre-synaptic membrane 
B)  binding of acetylcholine to muscle cell receptors 
C)  reuptake of acetylcholine by the nerve cell 
D)  hydrolysis of acetylcholine by acetylcholinesterase 
E)  release of acetylcholine by the nerve cell

Question 14

What is the [Na+]in/[Na+]out ratio created by depolarization in a nerve cell if the final potential is +50 mV at 37 $\degree$C?

Accepted Answer

A)  6.4  *  106 
B)  6.5 
C)  1.5 
D)  0.15 
E)  1.6  *  10-7 
A)  6.4  *  106 
B)  6.5 
C)  1.5 
D)  0.15 
E)  1.6  *  10-7

Question 15

Which amino acid in the aquaporin channel hydrogen bonds with water to prevent the movement of protons?

Accepted Answer

A)  Asn 
B)  Leu 
C)  Phe 
D)  Val 
E)  Ile 
A)  Asn 
B)  Leu 
C)  Phe 
D)  Val 
E)  Ile

Question 16

Serotonin reuptake occurs by a(n) _____.

Accepted Answer

A)  uniporter 
B)  antiporter using Na+ 
C)  antiporter using Ca2+ 
D)  symporter using Na+ 
E)  symporter using Ca2+ 
A)  uniporter 
B)  antiporter using Na+ 
C)  antiporter using Ca2+ 
D)  symporter using Na+ 
E)  symporter using Ca2+

Question 17

After depolarization of a nerve cell, what event restores the resting potential?

Accepted Answer

A)  K+ efflux 
B)  K+ influx 
C)  Na+ efflux 
D)  Na+ influx 
E)  Cl- efflux 
A)  K+ efflux 
B)  K+ influx 
C)  Na+ efflux 
D)  Na+ influx 
E)  Cl- efflux

Question 18

For a cell with [Na+]out = 150 mM and [Na+]in = 15 mM at 37 $\degree$C, what is the free energy for movement of sodium ions from outside the cell to inside if the potential across the membrane is -60 mV?

Accepted Answer

A)  11.7 kJ/mol 
B)  0.145 kJ/mol 
C)  -0.145 kJ/mol 
D)  -11.7 kJ/mol 
E)  cannot be calculated from given information 
A)  11.7 kJ/mol 
B)  0.145 kJ/mol 
C)  -0.145 kJ/mol 
D)  -11.7 kJ/mol 
E)  cannot be calculated from given information

Question 19

Inside a nerve cell at rest, [Na+] is _____ and [K+] _____ relative to the concentrations seen outside the cell.

Accepted Answer

A)  high; high 
B)  high; low 
C)  low; high 
D)  low; low 
E)  low; equal 
A)  high; high 
B)  high; low 
C)  low; high 
D)  low; low 
E)  low; equal

Question 20

What is the membrane potential created by a sodium gradient where [Na+]out = 145 mM and [Na+]in = 12mM at 37 $\degree$C?

Accepted Answer

A)  67 mV 
B)  7.9 mV 
C)  -7.9 mV 
D)  -29 mV 
E)  -67 mV 
A)  67 mV 
B)  7.9 mV 
C)  -7.9 mV 
D)  -29 mV 
E)  -67 mV

Exam 9: Membrane Transport

Transport of glucose from the intestine into the intestinal cells is accomplished by a(n) ________. This is an example of ___________.

At the neuromuscular synapse, acetylcholine is stored in vesicles in the ___ while acetylcholine receptors are found on the ___.

Which type of ion channel is blocked by lidocaine, a local anesthetic?

Which of the following statements regarding membrane transporters is true?

Which of the following occurs during the fusion of a synaptic vesicle and cell membrane?

Pinocytosis is a specific type of exocytosis where small amounts of intracellular material are sequestered in a vesicle followed by membrane fusion and transport of the material to the outside of the cell.

Which of the following will cause the opening or closing of a gated ion channel?

The P-glycoprotein is an example of a(n) _____ which has been linked to drug resistance in the treatment of _____.

Which of the following is true regarding SNARE complex formation?

Exosomes often contain ___ And ___

During receptor-mediated endocytosis, the movement of the receptor-ligand complex requires the presence of ___ that functions by mediating ___.

Which of the following is true regarding the glucose transporter?

Which of the following would be the first to occur following opening of Ca2+ channels during acetylcholine-mediated neurotransmission to a muscle cell?

What is the [Na+]in/[Na+]out ratio created by depolarization in a nerve cell if the final potential is +50 mV at 37 °\degree° C?

Which amino acid in the aquaporin channel hydrogen bonds with water to prevent the movement of protons?

Serotonin reuptake occurs by a(n) _____.

After depolarization of a nerve cell, what event restores the resting potential?

For a cell with [Na+]out = 150 mM and [Na+]in = 15 mM at 37 °\degree° C, what is the free energy for movement of sodium ions from outside the cell to inside if the potential across the membrane is -60 mV?

Inside a nerve cell at rest, [Na+] is _____ and [K+] _____ relative to the concentrations seen outside the cell.

What is the membrane potential created by a sodium gradient where [Na+]out = 145 mM and [Na+]in = 12mM at 37 °\degree° C?

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Transport of glucose from the intestine into the intestinal cells is accomplished by a(n) . This is an example of ___.

At the neuromuscular synapse, acetylcholine is stored in vesicles in the _ while acetylcholine receptors are found on the _.

The P-glycoprotein is an example of a(n) _ which has been linked to drug resistance in the treatment of _.

Exosomes often contain _ And _

During receptor-mediated endocytosis, the movement of the receptor-ligand complex requires the presence of _ that functions by mediating _.

Which of the following would be the first to occur following opening of Ca²⁺ channels during acetylcholine-mediated neurotransmission to a muscle cell?

What is the [Na⁺]_in/[Na⁺]_out ratio created by depolarization in a nerve cell if the final potential is +50 mV at 37 $\degree$ C?

For a cell with [Na⁺]_out = 150 mM and [Na⁺]_in = 15 mM at 37 $\degree$ C, what is the free energy for movement of sodium ions from outside the cell to inside if the potential across the membrane is -60 mV?

Inside a nerve cell at rest, [Na⁺] is _ and [K⁺] _ relative to the concentrations seen outside the cell.

What is the membrane potential created by a sodium gradient where [Na⁺]_out = 145 mM and [Na⁺]_in = 12mM at 37 $\degree$ C?