Question 1

A transport system that moves one solute into the cell and another one out of the cell during a single cycle accompanied by the expenditure of energy through ATP hydrolysis could be called a(n)_______

Accepted Answer

A) active antiport 
B) active uniport 
C) passive antiport 
D) active symport 
E) passive symport

Question 2

What technique can clarify the dynamic events that occur as a protein functions by introducing into the protein chemical groups (called nitroxides)that contain an unpaired electron? The properties of these nitroxides are sensitive to the distance that separates them and the unpaired electron produces a characteristic spectrum that can be monitored by the technique in question.The technique yields information about the distance between selected protein residues.

Accepted Answer

A) site-directed mutagenesis 
B) site-directed amenuensis 
C) hydropathy plots 
D) electron paramagnetic resonance (EPR)spectroscopy 
E) infrared spectroscopy

Question 3

What is caused by the inability of Na+ ion channels to open for several milliseconds after their inactivation?

Accepted Answer

A) hyperpolarization 
B) depolarization 
C) termination 
D) a refractory period 
E) an action potential

Question 4

What is thought to be important in maintaining the native structure of the Kv channel membrane protein and promoting its function as a voltage-gated channel.

Accepted Answer

A) negatively charged cholesterol 
B) positively charged sphingolipids 
C) negatively charged phospholipids 
D) positively charged phospholipids 
E) negatively charged sphingolipids

Question 5

You are the biologist on an interstellar spacecraft and discover a life form.It appears similar to life forms on Earth.You extract a number of molecules from the organism and characterize them.From the described properties,what kind of molecules are they likely to be and where are they likely to be found?
A.an amphipathic molecule that has two long hydrocarbon chains and a polar oligosaccharide head group.
B.another amphipathic molecule with two hydrocarbon chains and a phosphate-containing head group.
C.a polymer made of amino acids with hydrophobic amino acids on its outer surface in the middle of the molecule and hydrophilic amino acids on its outer surface on each end of the molecule.

Accepted Answer

The answer of You are the biologist on an interstellar...

Question 6

A rat cell and a chimpanzee cell are fused together.Antibodies to chimpanzee membrane antigens are labeled with rhodamine (a red fluorescent molecule)and antibodies against rat antigens are labeled with fluorescein (a green fluorescent molecule).What do the cells look like immediately after fusion? What about 40 minutes later? If the temperature of the cell is increased,what should happen?

Accepted Answer

The answer of A rat cell and a chimpanzee cell...

Question 7

How do Na+ ions enter a neuron when an action potential is initiated?

Accepted Answer

A) the Na+/K+-ATPase 
B) a gated Na+ pump 
C) a voltage-gated Na+ channel 
D) the ligand-gated Na+ channel 
E) a voltage-gated Na+ facilitated transporter

Question 8

The ability,possessed by all organisms,to respond to external stimulation is known as _______.

Accepted Answer

A) excitation 
B) irritability 
C) irritation 
D) irrigation 
E) irrigatability

Question 9

On average,how many amino acids engaged in predominantly hydrophobic $\alpha$- helices does it take to cross the hydrophobic part of the membrane?

Accepted Answer

A) about 10 amino acids 
B) about 20 amino acids 
C) at least 40 amino acids 
D) about 2 - 3 amino acids 
E) None of these are correct.

Question 10

You modify the gene for an integral membrane protein so that the cytoplasmic portions of the protein are deleted.When the gene is inserted in cells,what happens to the mobility of this protein in the membrane?

Accepted Answer

A) They move much greater distances than the intact protein. 
B) They move much smaller distances than the intact protein. 
C) They do not move at all. 
D) They are not inserted into the membrane so nothing can be learned about their mobility. 
E) They flip to the opposite leaflet.

Question 11

In the figure below,why is the stealth liposome coated with polyethylene glycol? What directs the stealth liposome to its target body tissue? Where are lipid-soluble drugs and water-soluble drugs found in stealth liposomes?

Accepted Answer

The answer of In the figure below,why is the stealth...

Question 12

In the Na+/glucose cotransporter,_____ moving down its gradient drives the transport of _____ against its gradient.

Accepted Answer

A) Na+ ions,K+ ions 
B) Na+ ions,glucose 
C) glucose,Na+ ions 
D) glucose,K+ ions 
E) K+ ions,glucose

Question 13

Impulse propagation by a myelinated axon is called ________ conduction.

Accepted Answer

A) saltatory 
B) myelinated 
C) rapid fire 
D) jump stop 
E) leap frog

Question 14

Where cells are the most affected by CF? Describe two potential treatments for these symptoms.What are the advantages and disadvantages of lipid-based delivery of the normal CFTR gene?

Accepted Answer

The answer of Where cells are the most affected by...

Question 15

What word below characterizes the amino acids that are found in an $\alpha$-helical segment that spans a membrane?

Accepted Answer

A) exclusively circular 
B) predominantly hydrophilic 
C) predominantly hydrophobic 
D) predominantly antiparallel 
E) totally parallel

Question 16

You are studying a transport molecule.It appears to bind temporarily to the molecule to be transported.During normal transport,no energy is expended.The addition of a particular molecule that closely resembles the normally transported molecule inhibits transport.An increase in the concentration of the normally transported molecule in the presence of a constant concentration of the inhibitor increases the rate of transport.What kind of transport is described and what is the inhibiting molecule?

Accepted Answer

The answer of You are studying a transport molecule.It appears...

Question 17

How was it proved that the cystic fibrosis transmembrane conductance regulator (CFTR)was actually a chloride transporter?

Accepted Answer

The answer of How was it proved that the cystic...

Question 18

In the figure below,what color should the fused mouse and human cell be 40 minutes after the fusion has occurred?

Accepted Answer

The answer of In the figure below,what color should the...

Question 19

_________ is the movement of a substance from an area of high concentration to an area of lower concentration.

Accepted Answer

A) Denaturation 
B) Osmosis 
C) Diffusion 
D) Transport 
E) Defusion

Question 20

An important aspect of transport by facilitated transporters and pumps is ________.

Accepted Answer

A) conformational shifts 
B) rigidity 
C) softness 
D) $\alpha$-helix 
E) $\beta$-pleated sheet

Exam 4: The Structure and Function of the Plasma Membrane

A transport system that moves one solute into the cell and another one out of the cell during a single cycle accompanied by the expenditure of energy through ATP hydrolysis could be called a(n) _______

What is caused by the inability of Na+ ion channels to open for several milliseconds after their inactivation?

What is thought to be important in maintaining the native structure of the Kv channel membrane protein and promoting its function as a voltage-gated channel.

How do Na+ ions enter a neuron when an action potential is initiated?

The ability,possessed by all organisms,to respond to external stimulation is known as _______.

On average,how many amino acids engaged in predominantly hydrophobic $\alpha$ - helices does it take to cross the hydrophobic part of the membrane?

You modify the gene for an integral membrane protein so that the cytoplasmic portions of the protein are deleted.When the gene is inserted in cells,what happens to the mobility of this protein in the membrane?

In the figure below,why is the stealth liposome coated with polyethylene glycol? What directs the stealth liposome to its target body tissue? Where are lipid-soluble drugs and water-soluble drugs found in stealth liposomes?

In the Na+/glucose cotransporter,_ moving down its gradient drives the transport of _ against its gradient.

Impulse propagation by a myelinated axon is called ________ conduction.

Where cells are the most affected by CF? Describe two potential treatments for these symptoms.What are the advantages and disadvantages of lipid-based delivery of the normal CFTR gene?

What word below characterizes the amino acids that are found in an $\alpha$ -helical segment that spans a membrane?

How was it proved that the cystic fibrosis transmembrane conductance regulator (CFTR)was actually a chloride transporter?

In the figure below,what color should the fused mouse and human cell be 40 minutes after the fusion has occurred?

_________ is the movement of a substance from an area of high concentration to an area of lower concentration.

An important aspect of transport by facilitated transporters and pumps is ________.

Exam 4: The Structure and Function of the Plasma Membrane

A transport system that moves one solute into the cell and another one out of the cell during a single cycle accompanied by the expenditure of energy through ATP hydrolysis could be called a(n) _______

What is caused by the inability of Na+ ion channels to open for several milliseconds after their inactivation?

What is thought to be important in maintaining the native structure of the Kv channel membrane protein and promoting its function as a voltage-gated channel.

How do Na+ ions enter a neuron when an action potential is initiated?

The ability,possessed by all organisms,to respond to external stimulation is known as _______.

On average,how many amino acids engaged in predominantly hydrophobic α\alphaα - helices does it take to cross the hydrophobic part of the membrane?

You modify the gene for an integral membrane protein so that the cytoplasmic portions of the protein are deleted.When the gene is inserted in cells,what happens to the mobility of this protein in the membrane?

In the figure below,why is the stealth liposome coated with polyethylene glycol? What directs the stealth liposome to its target body tissue? Where are lipid-soluble drugs and water-soluble drugs found in stealth liposomes?

In the Na+/glucose cotransporter,_____ moving down its gradient drives the transport of _____ against its gradient.

Impulse propagation by a myelinated axon is called ________ conduction.

Where cells are the most affected by CF? Describe two potential treatments for these symptoms.What are the advantages and disadvantages of lipid-based delivery of the normal CFTR gene?

What word below characterizes the amino acids that are found in an α\alphaα -helical segment that spans a membrane?

How was it proved that the cystic fibrosis transmembrane conductance regulator (CFTR)was actually a chloride transporter?

In the figure below,what color should the fused mouse and human cell be 40 minutes after the fusion has occurred?

_________ is the movement of a substance from an area of high concentration to an area of lower concentration.

An important aspect of transport by facilitated transporters and pumps is ________.

On average,how many amino acids engaged in predominantly hydrophobic $\alpha$ - helices does it take to cross the hydrophobic part of the membrane?

In the Na+/glucose cotransporter,_ moving down its gradient drives the transport of _ against its gradient.

What word below characterizes the amino acids that are found in an $\alpha$ -helical segment that spans a membrane?