Question 1

Which of the following mutations would be most likely to interfere with the proper insertion of a protein in the plasma membrane?

Accepted Answer

A)  a polar amino acid to a non-polar amino acid within a transmembrane domain
B)  a non-polar amino acid to a polar amino acid within a transmembrane domain
C)  a polar amino acid to a non-polar amino acid within a cytoplasmic domain
D)  a non-polar amino acid to a polar amino acid within a cytoplasmic domainE) A) and B)
F) All of the above

Question 2

GABAA receptors play an essential role in neurotransmission in the central nervous system.In response to the appropriate signal,these receptors open up and allow Cl- to flow into the cell.Given this information,GABAA receptors can be classified as a

Accepted Answer

A)  gated ion channel.
B)  gated carrier protein.
C)  symporter.
D)  Cl- pump.E) A) and B)
F) All of the above

Question 3

Protein X contains four transmembrane domains,a short N-terminus and a long C-terminus.Following protein synthesis,the N-terminus of the protein faces the lumen (the inside) of the ER.After protein X is transported to the cell surface via exocytosis,you would expect the C-terminus of the protein X to be

Accepted Answer

A)  extracellular.
B)  cytoplasmic.
C)  in the lumen.
D)  in the lipid bilayer of the plasma membrane.E) B) and C)
F) B) and D) A

Question 4

Osmosis occurs as water can cross the lipid bilayer through __________________,specialized channels for water movement.

Accepted Answer

A)  proteins
B)  carbohydrates
C)  membrane pores
D)  aquaporinsE) C) and D)
F) A) and D)

Question 5

The cell's transactions with the environment mediated by its plasma membrane include all of the following except

Accepted Answer

A)  ingesting food as molecules and sometimes as entire cells.
B)  returning waste and other molecules back to the environment.
C)  responding to a host of chemical cues.
D)  directing the synthesis of various food-digesting proteins.
E)  passing of messages to other cells.F) A) and D)
G) A) and B)

Question 6

As a scientist you perform an experiment in which you create an artificial cell with a selectively permeable membrane through which only water can pass.You put a 5M solution of glucose into the cell and you place that into a beaker of 10M glucose.What observations do you expect to see?

Accepted Answer

A)  Water moves out of the cell.
B)  Glucose moves out of the cell.
C)  No net change in cell weight.
D)  Water moves into the cell.
E)  Glucose moves into the cell.F) C) and D)
G) A) and B)

Question 7

________ is the net movement of substances to regions of lower concentration.

Accepted Answer

A)  Osmosis
B)  Active transport
C)  Facilitation
D)  DiffusionE) All of the above
F) None of the above

Question 8

Carrier-mediated transport is also called

Accepted Answer

A)  facilitated diffusion.
B)  active transport.
C)  exocytosis.
D)  endocytosis.
E)  phagocytosis.F) C) and D)
G) B) and D)

Question 9

The accumulation of amino acids and sugars in animal cells occurs through

Accepted Answer

A)  ATP pumps.
B)  sodium-potassium pumps.
C)  glucose pumps.
D)  coupled transport.
E)  proton pumps.F) C) and D)
G) A) and D) D

Question 10

Which of the following statements about receptor-mediated endocytosis is false?

Accepted Answer

A)  Receptor-mediated endocytosis is a dynamic process.
B)  Receptor-mediated endocytosis indirectly helps to increase membrane fluidity by helping to transport cholesterol into the cell.
C)  Receptor-mediated endocytosis requires a clathrin coat.
D)  Receptor-mediated endocytosis is used to internalize molecules into the cytoplasm of the cell.E) A) and B)
F) All of the above

Question 11

The fluid nature of the membranes is attributed to a lateral movement of

Accepted Answer

A)  protein channels.
B)  phospholipid molecules.
C)  antigen molecules.
D)  pumps such as the proton pump.
E)  the entire lipid bilayer.F) A) and D)
G) A) and C)

Question 12

In a single sodium-potassium pump cycle,ATP is used up with the result that

Accepted Answer

A)  3 sodium ions leave and 2 potassium ions enter.
B)  1 sodium ion enters and 1 potassium ion leaves.
C)  1 sodium ion leaves and 1 potassium ion enters.
D)  3 sodium ions enter and 2 potassium ions leave.
E)  sodium and potassium ions enter and water leaves.F) A) and D)
G) A) and E)

Question 13

During neuronal signaling,a change in membrane potential will cause sodium channels to open and let Na+ ions diffuse down their concentration gradient into the cell.Which of the following helps establish the concentration gradient necessary for this process to occur?

Accepted Answer

A)  Na+/K+ channel
B)  voltage-gated Na+ channel
C)  Na+ symporter
D)  Na+/K+ pumpE) A) and B)
F) None of the above

Question 14

Cyclodextrins can be used to remove cholesterol from a membrane.Which of the following is the most likely effect of cyclodextrin treatment?

Accepted Answer

A)  an increase in transmembrane proteins
B)  a disruption of the bilayer
C)  an increase in membrane fluidity
D)  a disruption of lipid raftsE) B) and D)
F) None of the above

Question 15

Both active transport and facilitated transport utilize specific ______________ proteins embedded in the cell membrane.

Accepted Answer

A)  carrier
B)  cytoskeletal
C)  structural
D)  targetedE) A) and B)
F) B) and C)

Question 16

A type of transport of a solute across a membrane,up its concentration gradient,using protein carriers driven by the expenditure of chemical energy is known as

Accepted Answer

A)  osmosis.
B)  diffusion.
C)  facilitated transport.
D)  active transport.
E)  exocytosis.F) A) and E)
G) A) and C)

Question 17

The movement of substances to regions of lower concentration is called

Accepted Answer

A)  active transport.
B)  diffusion.
C)  osmosis.
D)  pumping.
E)  exocytosis.F) A) and E)
G) B) and D)

Question 18

One day during the summer you and some friends made ice cream using an electric ice cream maker.A few days later you noticed a yellow circle of dead grass where the ice cream freezer had been placed.What happened?

Accepted Answer

A)  The ice and salt mixture that spilled out when the freezer was moved froze the grass.
B)  The grass was frost bitten by the ice and salt mixture that spilled out when the freezer was moved.
C)  The ice and salt mixture was isosmotic to the grass cells and caused the yellow circle of dead grass.
D)  The ice and salt mixture was hyperosmotic to the grass cells and caused the yellow circle of dead grass.
E)  The ice and salt mixture was hypoosmotic to the grass cells and caused the yellow circle of dead grass.F) A) and E)
G) A) and B)

Question 19

On the outer surface of the plasma membrane there are marker molecules that identify the cell-type.Often these molecules are

Accepted Answer

A)  ATP.
B)  amino acids.
C)  nucleotides.
D)  carbohydrate chains.
E)  inorganic ions.F) D) and E)
G) B) and E) D

Question 20

Osmosis can only occur if water travels through the

Accepted Answer

A)  cell wall.
B)  semi-permeable membrane.
C)  vacuole.
D)  ER.
E)  cytoskeleton.F) A) and E)
G) A) and C)

Exam 5: Membranes

Which of the following mutations would be most likely to interfere with the proper insertion of a protein in the plasma membrane?

Correct Answer
verified

GABA_A receptors play an essential role in neurotransmission in the central nervous system.In response to the appropriate signal,these receptors open up and allow Cl^- to flow into the cell.Given this information,GABA_A receptors can be classified as a

Correct Answer
verified

Correct Answer
verified
A

Osmosis occurs as water can cross the lipid bilayer through __________________,specialized channels for water movement.

Correct Answer
verified

The cell's transactions with the environment mediated by its plasma membrane include all of the following except

Correct Answer
verified

As a scientist you perform an experiment in which you create an artificial cell with a selectively permeable membrane through which only water can pass.You put a 5M solution of glucose into the cell and you place that into a beaker of 10M glucose.What observations do you expect to see?

Correct Answer
verified

________ is the net movement of substances to regions of lower concentration.

Correct Answer
verified

Carrier-mediated transport is also called

Correct Answer
verified

The accumulation of amino acids and sugars in animal cells occurs through

Correct Answer
verified
D

Which of the following statements about receptor-mediated endocytosis is false?

Correct Answer
verified

The fluid nature of the membranes is attributed to a lateral movement of

Correct Answer
verified

In a single sodium-potassium pump cycle,ATP is used up with the result that

Correct Answer
verified

During neuronal signaling,a change in membrane potential will cause sodium channels to open and let Na⁺ ions diffuse down their concentration gradient into the cell.Which of the following helps establish the concentration gradient necessary for this process to occur?

Correct Answer
verified

Cyclodextrins can be used to remove cholesterol from a membrane.Which of the following is the most likely effect of cyclodextrin treatment?

Correct Answer
verified

Both active transport and facilitated transport utilize specific ______________ proteins embedded in the cell membrane.

Correct Answer
verified

A type of transport of a solute across a membrane,up its concentration gradient,using protein carriers driven by the expenditure of chemical energy is known as

Correct Answer
verified

The movement of substances to regions of lower concentration is called

Correct Answer
verified

One day during the summer you and some friends made ice cream using an electric ice cream maker.A few days later you noticed a yellow circle of dead grass where the ice cream freezer had been placed.What happened?

Correct Answer
verified

On the outer surface of the plasma membrane there are marker molecules that identify the cell-type.Often these molecules are

Correct Answer
verified
D

Osmosis can only occur if water travels through the

Correct Answer
verified

Exam 5: Membranes

Which of the following mutations would be most likely to interfere with the proper insertion of a protein in the plasma membrane?

Correct AnswerverifiedShow Answer

GABAA receptors play an essential role in neurotransmission in the central nervous system.In response to the appropriate signal,these receptors open up and allow Cl- to flow into the cell.Given this information,GABAA receptors can be classified as a

Correct AnswerverifiedShow Answer

Correct AnswerverifiedA

Osmosis occurs as water can cross the lipid bilayer through __________________,specialized channels for water movement.

Correct AnswerverifiedShow Answer

The cell's transactions with the environment mediated by its plasma membrane include all of the following except

Correct AnswerverifiedShow Answer

As a scientist you perform an experiment in which you create an artificial cell with a selectively permeable membrane through which only water can pass.You put a 5M solution of glucose into the cell and you place that into a beaker of 10M glucose.What observations do you expect to see?

Correct AnswerverifiedShow Answer

________ is the net movement of substances to regions of lower concentration.

Correct AnswerverifiedShow Answer

Carrier-mediated transport is also called

Correct AnswerverifiedShow Answer

The accumulation of amino acids and sugars in animal cells occurs through

Correct AnswerverifiedD

Which of the following statements about receptor-mediated endocytosis is false?

Correct AnswerverifiedShow Answer

The fluid nature of the membranes is attributed to a lateral movement of

Correct AnswerverifiedShow Answer

In a single sodium-potassium pump cycle,ATP is used up with the result that

Correct AnswerverifiedShow Answer

During neuronal signaling,a change in membrane potential will cause sodium channels to open and let Na+ ions diffuse down their concentration gradient into the cell.Which of the following helps establish the concentration gradient necessary for this process to occur?

Correct AnswerverifiedShow Answer

Cyclodextrins can be used to remove cholesterol from a membrane.Which of the following is the most likely effect of cyclodextrin treatment?

Correct AnswerverifiedShow Answer

Both active transport and facilitated transport utilize specific ______________ proteins embedded in the cell membrane.

Correct AnswerverifiedShow Answer

A type of transport of a solute across a membrane,up its concentration gradient,using protein carriers driven by the expenditure of chemical energy is known as

Correct AnswerverifiedShow Answer

The movement of substances to regions of lower concentration is called

Correct AnswerverifiedShow Answer

One day during the summer you and some friends made ice cream using an electric ice cream maker.A few days later you noticed a yellow circle of dead grass where the ice cream freezer had been placed.What happened?

Correct AnswerverifiedShow Answer

On the outer surface of the plasma membrane there are marker molecules that identify the cell-type.Often these molecules are

Correct AnswerverifiedD

Osmosis can only occur if water travels through the

Correct AnswerverifiedShow Answer

Correct Answer
verified

GABA_A receptors play an essential role in neurotransmission in the central nervous system.In response to the appropriate signal,these receptors open up and allow Cl^- to flow into the cell.Given this information,GABA_A receptors can be classified as a

Correct Answer
verified

Correct Answer
verified
A

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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D

Correct Answer
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Correct Answer
verified

Correct Answer
verified

During neuronal signaling,a change in membrane potential will cause sodium channels to open and let Na⁺ ions diffuse down their concentration gradient into the cell.Which of the following helps establish the concentration gradient necessary for this process to occur?

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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D

Correct Answer
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