Question 1

When blood supplies oxygen and food to a cell surface and these molecules diffuse across,we might expect some "resting time." However,if we inspected most cell membranes in a living human body,we would find a nearly continuous flow of substances back-and-forth across the plasma membrane.Which of the following is not a reason why?

Accepted Answer

A)  Cell metabolism is constantly using up oxygen and raw materials; this lowers their concentration so more will diffuse into the cell.
B)  Cell metabolism is constantly producing waste molecules; this increases their concentration so more will diffuse out of the cell.
C)  Cells produce useful secretions; this increases their concentration and more will diffuse out of the cell.
D)  Cell metabolism constantly produces carbon dioxide in respiration; this increases its concentration so more will diffuse out of the cell.
E)  Cells are living entities and in order to live can never "rest."

Question 2

A cell placed in a hypotonic solution will

Accepted Answer

A)  lose water.
B)  gain water.
C)  neither gain nor lose water.
D)  lose water initially and then gain water.
E)  gain water initially and then lose water.

Question 3

If a cell lacks ATP,which of the following processes would cease to operate immediately?

Accepted Answer

A)  diffusion
B)  sodium/potassium pump
C)  facilitated diffusion
D)  osmosis
E)  tonicity

Question 4

A student sitting on the back row opened a bottle of foul-smelling perfume and dabbed it on her wrists.One by one (beginning from the back of the room) the students began to cough due to the foul smell.This phenomena was due to

Accepted Answer

A)  osmosis.
B)  molecules moving from an area of low concentration to high concentration.
C)  an allergic reaction.
D)  diffusion.
E)  active transport.

Question 5

List the three types of intercelluar junctions found in animal cells and indicate their function.

Accepted Answer

Adhesion junctions: form a sturdy but fl...

Question 6

The definition of osmosis is the

Accepted Answer

A)  the movement of solute molecules from a higher concentration to a lower concentration.
B)  diffusion of water across a selectively permeable membrane.
C)  likelihood that water will diffuse in a particular direction.
D)  lower concentration of a solute in a solution.
E)  movement of water toward a higher water concentration.

Question 7

A differentially permeable membrane separates a molasses solution from distilled water.Over time,the

Accepted Answer

A)  molasses will be found in the water.
B)  molasses will become more dilute.
C)  molasses solution will become more concentrated.
D)  molasses will be found in water and it will be more concentrated.
E)  solutions will remain the same.

Question 8

Permeability refers to

Accepted Answer

A)  the movement of molecules from an area of greater concentration to an area of lesser concentration.
B)  the extent to which a membrane allows a substance to pass through.
C)  the amount of solute in a solution.
D)  the state of being permanent.
E)  the ability to establish a permanent solute level in a solution.

Question 9

When water enters a plant cell

Accepted Answer

A)  it bursts.
B)  the vacuole becomes enlarged.
C)  the vacuole shrinks.
D)  it undergoes plasmolysis.
E)  it undergoes crenation.

Question 10

Which components of a cell membrane are used for cell-to-cell recognition?

Accepted Answer

A)  phospholipids
B)  channel proteins
C)  glycolipids
D)  glycoproteins
E)  cholesterol molecules

Question 11

Which of the following molecules add stiffness and strength to the plasma membrane?

Accepted Answer

A)  glycoproteins
B)  cholesterol
C)  phospholipids
D)  enzymatic proteins
E)  phosphate groups

Question 12

Oxygen diffuses into the capillaries of the lungs because there is

Accepted Answer

A)  a higher concentration of O2 in the alveoli than the capillaries.
B)  a higher concentration of O2 in the capillaries than the alveoli.
C)  a higher concentration of CO2 in the alveoli than the capillaries.
D)  a higher concentration of CO2 in capillaries than the alveoli.
E)  an equal concentration of O2 in the alveoli and the capillaries.

Question 13

Which statement is false concerning movement of molecules across the cell membrane?

Accepted Answer

A)  Water and gas molecules have no difficulty.
B)  Small uncharged molecules pass through easily.
C)  Large molecules do not pass through easily.
D)  Charged molecules do not pass through easily.
E)  Lipid molecules do not pass through easily.

Question 14

Kidney dialysis relies on diffusion of various dissolved waste molecules (solutes) across a non-living semipermeable membrane.If the concentration of solutes in the blood increases over time before dialysis is administered,what will happen to the rate of dialysis when it occurs?

Accepted Answer

A)  It will remain the same since there are no carrier molecules in a non-living membrane.
B)  The rate will slow down since the solute is more viscous.
C)  The rate will speed up since the concentration gradient is higher.
D)  It will remain the same since there is no active transport in a non-living membrane.
E)  The rate will depend on the amount of time given for diffusion to take place.

Question 15

Carrier molecules are required for

Accepted Answer

A)  osmosis.
B)  both osmosis AND diffusion.
C)  facilitated diffusion.
D)  active transport.
E)  both facilitated diffusion AND active transport.

Question 16

Red blood cells come in many blood types including A,B,AB,and type O (lacking proteins A and B) ,Rh positive,Rh negative (lacking Rh+) ,and many others.If blood is transfused,the recipient detects any new or foreign proteins.The blood type proteins are

Accepted Answer

A)  in the red blood cell nucleus.
B)  inside the red blood cell cytoplasm.
C)  on the outer surface of the red blood cell membrane.
D)  in the nuclear membrane.
E)  in the endoplasmic reticulum of the red blood cells.

Question 17

When a substance moves from an area of low concentration to an area of high concentration while using energy,the process is termed

Accepted Answer

A)  diffusion.
B)  osmosis.
C)  facilitated diffusion.
D)  pinocytosis.
E)  active transport.

Question 18

Which is a correct example of tonicity?

Accepted Answer

A)  Water is hypertonic to red blood cells.
B)  Turgor pressure is created when a plant cell swells in a hypotonic solution.
C)  Plasmolysis results from plant cells in hypotonic solutions.
D)  Crenated red blood cells result when they are placed in a hypotonic solution.
E)  If a cell is placed in a hypertonic solution,water enters the cell.

Question 19

A cell is placed in a solution of large nutrient molecules tagged with a red dye.Soon the cell is dark red,showing a concentration of the nutrient much higher than the external solution.We add a reagent that blocks the use of ATP.What result would you expect from this experiment?

Accepted Answer

A)  The nutrient would continue to rapidly enter the cell by diffusion because as a nutrient it is constantly being used in cell metabolism,so the cell will get redder.
B)  The color will remain the same since all future transfer will stop.
C)  The color will fade as the import of the nutrient stops and diffustion evens the concentrations as it moves the nutrient molecules out of the cell.
D)  The cell will continue to get darker since the import of the nutrient does not involve ATP.
E)  The cell will die without access to ATP.

Question 20

Of the following conditions,which is absolutely necessary for diffusion to take place?

Accepted Answer

A)  a differentially permeable membrane
B)  a true solution
C)  a concentration difference
D)  a non-permeable membrane
E)  a living cell

Exam 4: Membrane Structure and Function

Which statement is false concerning movement of molecules across the cell membrane?

Correct Answer
verified

If a cell lacks ATP,which of the following processes would cease to operate immediately?

Correct Answer
verified

When a substance moves from an area of low concentration to an area of high concentration while using energy,the process is termed

Correct Answer
verified

A cell is placed in a solution of large nutrient molecules tagged with a red dye.Soon the cell is dark red,showing a concentration of the nutrient much higher than the external solution.We add a reagent that blocks the use of ATP.What result would you expect from this experiment?

Correct Answer
verified

Oxygen diffuses into the capillaries of the lungs because there is

Correct Answer
verified

Kidney dialysis relies on diffusion of various dissolved waste molecules (solutes) across a non-living semipermeable membrane.If the concentration of solutes in the blood increases over time before dialysis is administered,what will happen to the rate of dialysis when it occurs?

Correct Answer
verified

Carrier molecules are required for

Correct Answer
verified

Red blood cells come in many blood types including A,B,AB,and type O (lacking proteins A and B) ,Rh positive,Rh negative (lacking Rh+) ,and many others.If blood is transfused,the recipient detects any new or foreign proteins.The blood type proteins are

Correct Answer
verified

The definition of osmosis is the

Correct Answer
verified

Which components of a cell membrane are used for cell-to-cell recognition?

Correct Answer
verified

A differentially permeable membrane separates a molasses solution from distilled water.Over time,the

Correct Answer
verified

Correct Answer
verified

Which is a correct example of tonicity?

Correct Answer
verified

Of the following conditions,which is absolutely necessary for diffusion to take place?

Correct Answer
verified

Which of the following molecules add stiffness and strength to the plasma membrane?

Correct Answer
verified

A cell placed in a hypotonic solution will

Correct Answer
verified

Permeability refers to

Correct Answer
verified

A student sitting on the back row opened a bottle of foul-smelling perfume and dabbed it on her wrists.One by one (beginning from the back of the room) the students began to cough due to the foul smell.This phenomena was due to

Correct Answer
verified

When water enters a plant cell

Correct Answer
verified

List the three types of intercelluar junctions found in animal cells and indicate their function.

Correct Answer
verified
Adhesion junctions: form a sturdy but fl...
View Answer

Exam 4: Membrane Structure and Function

Which statement is false concerning movement of molecules across the cell membrane?

Correct AnswerverifiedShow Answer

If a cell lacks ATP,which of the following processes would cease to operate immediately?

Correct AnswerverifiedShow Answer

When a substance moves from an area of low concentration to an area of high concentration while using energy,the process is termed

Correct AnswerverifiedShow Answer

A cell is placed in a solution of large nutrient molecules tagged with a red dye.Soon the cell is dark red,showing a concentration of the nutrient much higher than the external solution.We add a reagent that blocks the use of ATP.What result would you expect from this experiment?

Correct AnswerverifiedShow Answer

Oxygen diffuses into the capillaries of the lungs because there is

Correct AnswerverifiedShow Answer

Kidney dialysis relies on diffusion of various dissolved waste molecules (solutes) across a non-living semipermeable membrane.If the concentration of solutes in the blood increases over time before dialysis is administered,what will happen to the rate of dialysis when it occurs?

Correct AnswerverifiedShow Answer

Carrier molecules are required for

Correct AnswerverifiedShow Answer

Red blood cells come in many blood types including A,B,AB,and type O (lacking proteins A and B) ,Rh positive,Rh negative (lacking Rh+) ,and many others.If blood is transfused,the recipient detects any new or foreign proteins.The blood type proteins are

Correct AnswerverifiedShow Answer

The definition of osmosis is the

Correct AnswerverifiedShow Answer

Which components of a cell membrane are used for cell-to-cell recognition?

Correct AnswerverifiedShow Answer

A differentially permeable membrane separates a molasses solution from distilled water.Over time,the

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which is a correct example of tonicity?

Correct AnswerverifiedShow Answer

Of the following conditions,which is absolutely necessary for diffusion to take place?

Correct AnswerverifiedShow Answer

Which of the following molecules add stiffness and strength to the plasma membrane?

Correct AnswerverifiedShow Answer

A cell placed in a hypotonic solution will

Correct AnswerverifiedShow Answer

Permeability refers to

Correct AnswerverifiedShow Answer

A student sitting on the back row opened a bottle of foul-smelling perfume and dabbed it on her wrists.One by one (beginning from the back of the room) the students began to cough due to the foul smell.This phenomena was due to

Correct AnswerverifiedShow Answer

When water enters a plant cell

Correct AnswerverifiedShow Answer

List the three types of intercelluar junctions found in animal cells and indicate their function.

Correct AnswerverifiedAdhesion junctions: form a sturdy but fl...View AnswerShow Answer

Correct Answer
verified

Correct Answer
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Correct Answer
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verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Adhesion junctions: form a sturdy but fl...
View Answer