Deck 5: Membrane Dynamics

Question 1

Voltage-gated (voltage-dependent)channels and antiport carriers are both types of

A) structural proteins.
B) enzymes.
C) transporters.
D) receptors.

Answer 1

C

Question 2

Water is a polar molecule,yet it easily moves through the nonpolar portions of cell membranes.Which transport process is responsible?

A) facilitated diffusion
B) simple diffusion
C) uniport
D) symport
E) antiport

Answer 2

B

Question 3

The means by which a cell transports large molecules out of the cell is called

A) phagocytosis.
B) endocytosis.
C) exocytosis.
D) diffusion.
E) active transport.

Answer 3

C

Question 4

Which of the following statements about the resting membrane potential is TRUE?

A) It is normally equal to zero volts.
B) The inside of the membrane is positively charged compared to the outside.
C) It results, in part, from the concentration gradients for Na⁺ and K^+.
D) It is due in part to the presence of extracellular proteins.

Question 5

Hyposmotic solutions

A) have higher concentrations of solutes than hyperosmotic solutions.
B) have lower concentrations of solutes than other hyposmotic solutions.
C) have the same concentration of solutes as hyperosmotic solutions.
D) have lower concentrations of solutes than hyperosmotic solutions.
E) None of the answers are correct.

Question 6

What are the two extracellular fluid compartments in the body?

A) intracellular and plasma
B) plasma and interstitial
C) interstitial and intracellular
D) plasma and the fluid portion of the blood
E) None of the answers are correct.

Question 7

Which body fluid compartment contains high levels of K⁺,large anions,and proteins?

A) plasma only
B) interstitial fluid only
C) intracellular fluid only
D) both plasma and intracellular fluid
E) both plasma and interstitial fluid

Question 8

The term cellular (metabolic)energy indicates any biological process requiring

A) energy in any form.
B) ATP.
C) thermal energy.
D) chemical energy.
E) thermal energy and chemical energy.

Question 9

Which body fluid compartment contains higher levels of Na⁺,Cl^-,and HCO₃^-?

A) plasma only
B) interstitial fluid only
C) intracellular fluid only
D) both plasma and intracellular fluid
E) both plasma and interstitial fluid

Question 10

Which of the following is a way for solutes in an aqueous solution to move from an area of high solute concentration to an area of low solute concentration?

A) only facilitated diffusion
B) only osmosis
C) only active transport
D) both facilitated diffusion and osmosis
E) None of the answers are correct.

Question 11

In an epithelium,the apical membrane is also known as the ________ membrane.

A) basolateral
B) mucosal
C) serosal
D) basement
E) nictitating

Question 12

Compared to the outside surface,the inside of a resting cell membrane is

A) positively charged.
B) negatively charged.
C) electrically neutral.
D) continuously reversing its electrical charge.
E) positively charged whenever the sodium-potassium pump is active.

Question 13

Permeability is a property of

A) membranes.
B) ions.
C) solutes.
D) solvents.
E) proteins.

Question 14

Saturation occurs when

A) molecules are moved by the use of vesicles.
B) the energy required to move molecules results from a high-energy bond.
C) a group of carrier proteins is operating at its maximum rate.
D) a preference of a carrier protein for a substance is demonstrated based on the differing affinities of the carrier for the substrates.
E) a carrier molecule has the ability to transport only one molecule or a group of closely related molecules.

Question 15

All of the following are types of mediated transport except one.Identify the exception.

A) facilitated diffusion
B) primary active transport
C) simple diffusion
D) secondary active transport

Question 16

Caveolae and clathrin-coated pits are both used in

A) endocytosis.
B) exocytosis.
C) phagocytosis.
D) All of the answers are correct.
E) None of the answers are correct.

Question 17

Which of the following statements about the Na⁺/K⁺ pump is FALSE?

A) It transports Na⁺ out of the cell and K⁺ into the cell.
B) It is present in neurons.
C) Its activity requires the expenditure of metabolic (cellular) energy.
D) It transports Na⁺ and K⁺ in a 1:1 ratio.

Question 18

As the charge on the membrane of a typical neuron approaches 0 from -70 mV,the cell is

A) only repolarizing.
B) only hyperpolarizing.
C) only depolarizing.
D) only becoming more difficult to stimulate.
E) hyperpolarizing and becoming more difficult to stimulate

Question 19

Bulk flow is fluid flow as a result of a(n)________ gradient.

A) concentration
B) electrical
C) pressure
D) Two of the answers are correct.
E) None of the answers are correct.

Question 20

The resting membrane potential in a typical nerve cell is approximately

A) +70 mV.
B) -70 mV.
C) +35 mV.
D) -35 mV.
E) 0 mV.

Question 21

Match the transport process to its description.
A.active transport
B.passive transport
the movement of molecules from an area of high concentration to an area of low concentration

Question 22

Match the membrane protein with its function.
A.transfer signals from the extracellular environment to the cytoplasm of the cell
B.form cell-to-cell connections
C.bind to molecules to facilitate entry to or exit from the cell
D.ligands bind to these proteins and are changed by the protein
enzymes

Question 23

Match the transport process to its description.
A.simple diffusion
B.facilitated diffusion
C.both
D.neither
the use of ATP to move molecules

Question 24

Match the transport process to its description.
A.active transport
B.passive transport
tends to create an equilibrium state

Question 25

Passive transport refers to a process that requires

A) no energy at all.
B) no cellular energy.
C) no pressure gradient.
D) no concentration gradient.
E) no electrical gradient.

Question 26

Match the transport process to its description.
A.simple diffusion
B.facilitated diffusion
C.both
D.neither
the movement of molecules from an area of high concentration to an area of low concentration

Question 27

Match the transport process to its description.
A.simple diffusion
B.facilitated diffusion
C.both
D.neither
conform(s)to the properties of specificity,competition,and saturation

Question 28

Match the transport process to its description.
A.active transport
B.passive transport
the movement of molecules via proteins embedded in the cell membrane; requires ATP

Question 29

Match the membrane protein with its function.
A.transfer signals from the extracellular environment to the cytoplasm of the cell
B.form cell-to-cell connections
C.bind to molecules to facilitate entry to or exit from the cell
D.ligands bind to these proteins and are changed by the protein
structural proteins

Question 30

The ion that plays a key role in initiating electrical signals in neurons is

A) K⁺.
B) Na⁺.
C) Cl^-.
D) Ca²⁺.

Question 31

Gated channels for sodium ions may include

A) mechanical gates, which respond to pressure.
B) chemical gates, which respond to ligands.
C) voltage gates, which respond to electrical signals.
D) All of the answers are correct.
E) None of the answers are correct.

Question 32

Match the membrane protein with its function.
A.transfer signals from the extracellular environment to the cytoplasm of the cell
B.form cell-to-cell connections
C.bind to molecules to facilitate entry to or exit from the cell
D.ligands bind to these proteins and are changed by the protein
transporters

Question 33

Match the membrane protein with its function.
A.transfer signals from the extracellular environment to the cytoplasm of the cell
B.form cell-to-cell connections
C.bind to molecules to facilitate entry to or exit from the cell
D.ligands bind to these proteins and are changed by the protein
receptors

Question 34

Which of the following is NOT true of diffusion in the human body?

A) Diffusion occurs faster at higher temperatures.
B) Smaller molecules take longer to diffuse than larger ones.
C) Net movement of molecules occurs until the osmolarity is equal.
D) Diffusion is rapid over short distances and slower over longer distances.

Question 35

Match the type of transport with its description.
A.secretion
B.paracellular transport
C.transcellular transport
D.absorption
between adjacent cells

Question 36

Which of the following is NOT involved in creating the resting potential of a neuron?

A) diffusion of potassium ions out of the cell
B) diffusion of sodium ions into the cell
C) resting membrane permeability for sodium ions greater than potassium ions
D) resting membrane permeability for potassium ions greater than sodium ions

Question 37

Match the transport process to its description.
A.active transport
B.passive transport
the movement of molecules against the concentration gradient

Question 38

Match the transport process to its description.
A.simple diffusion
B.facilitated diffusion
C.both
D.neither
a form of mediated transport

Question 39

Match the type of transport with its description.
A.secretion
B.paracellular transport
C.transcellular transport
D.absorption
from an organ's lumen to the extracellular fluid

Question 40

When a neuron changes its ion permeability from the resting state,

A) a variety of gated ion channels may open or close.
B) Na⁺ channels may open, allowing Na⁺ to enter the cell.
C) K⁺ channels must open, allowing K⁺ to enter the cell.
D) only a variety of gated ion channels may open or close and Na⁺ channels may open, allowing Na⁺ to enter the cell.
E) a variety of gated ion channels may open or close, Na⁺ channels may open, allowing Na⁺ to enter the cell, and K⁺ channels must open, allowing K⁺ to enter the cell.

Question 41

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
to -50 mV from resting potential

Question 42

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
to +30 mV from resting potential

Question 43

Match the type of transport with its description.
A.secretion
B.paracellular transport
C.transcellular transport
D.absorption
in one side of a cell and out the other

Question 44

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
any value other than 0 mV,regardless of relationship to resting potential

Question 45

Match the potential or potential change with the causative circumstances.Assume ion movements are net movements.Answers may be used more than once or not at all.
A.resting membrane potential
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
Na⁺ enters the cell

Question 46

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
to -70 mV from -50 mV

Question 47

Match the potential or potential change with the causative circumstances.Assume ion movements are net movements.Answers may be used more than once or not at all.
A.resting membrane potential
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
membrane potential is 0 mV

Question 48

The membrane proteins that catalyze reactions that take place on the external or internal surface of the cell are ________.

Question 49

The three types of gated channels are ________,________,and ________.

Question 50

Match the potential or potential change with the causative circumstances.Assume ion movements are net movements.Answers may be used more than once or not at all.
A.resting membrane potential
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
K⁺ leaves the cell

Question 51

Match the potential or potential change with the causative circumstances.Assume ion movements are net movements.Answers may be used more than once or not at all.
A.resting membrane potential
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
Cl^- enters the cell

Question 52

The membrane proteins that bind to a ligand and act in the body's chemical signaling system are ________.

Question 53

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
to -90 mV from resting potential

Question 54

The membrane proteins that provide for support of the cell membrane and allow for cells to connect to each other are ________.

Question 55

Membrane protein pores that can be opened and closed are called ________ channels.

Question 56

Match the type of transport with its description.
A.secretion
B.paracellular transport
C.transcellular transport
D.absorption
movement from the extracellular fluid into the lumen of an organ

Question 57

The membrane proteins that change shape and bind with specific molecules to transport them across the cell membrane are ________.

Question 58

This type of membrane protein extends all the way through the cell membrane into both the extra- and intracellular fluids: ________.

Question 59

Match the terms to changes presented,assuming a resting membrane potential of -70 mV.Answers may be used once,more than once,or not at all.
A.electrical polarization
B.hyperpolarization
C.depolarization
D.repolarization
E.more than one of the answers
to -70 mV from -90 mV

Question 60

Carrier proteins operating at their maximum rate are said to be ________.

Question 61

At rest,nerve cells have an unequal distribution of ions on either side of the cell membrane,producing the ________.

Question 62

Sodium ions are more concentrated in the extracellular fluid than in the intracellular fluid.This is an example of

A) electrical disequilibrium.
B) osmotic equilibrium.
C) chemical disequilibrium.
D) failed homeostasis.

Question 63

The walls of the ________ separate the two extracellular fluid compartments.

Question 64

At rest,nerve cells have a voltage of ________ mV.

Question 65

Which of the following would increase the rate of diffusion across a cell membrane?

A) a decrease in the surface area of the membrane
B) a decrease in the concentration gradient
C) a decrease in membrane permeability
D) a decrease in membrane thickness

Question 66

A cell membrane that is selectively permeable

A) randomly chooses which substances will pass through.
B) can change which substances pass through by changing its lipid and protein content.
C) is impermeable to all substances but water.
D) will only allow substances in or out if their concentration in the cell is above or below a certain point.

Question 67

Pinocytosis and potocytosis are types of

A) endocytosis.
B) exocytosis.
C) phagocytosis.
D) endocytosis and exocytosis.
E) exocytosis and phagocytosis.

Question 68

Membrane protein pores that are essentially always open are called ________ or ________ channels.

Question 69

Substances that readily dissolve in water and do not readily dissolve in lipids are

A) hydrophobic and lipophobic.
B) hydrophilic and lipophobic.
C) hydrophobic and lipophilic.
D) hydrophilic and lipophilic.

Question 70

Water will always move from ________ areas to ________ areas,if there are no impermeable barriers.

A) hyperosmotic, hyposmotic
B) hyposmotic, hyperosmotic
C) isosmotic, hyposmotic
D) hyperosmotic, isosmotic

Question 71

A pump that helps maintain an electrical gradient,such as the Na⁺-K⁺-ATPase is a(n)________ pump.

Question 72

Channel proteins that allow water to pass are called ________.

Question 73

Which property of diffusion best helps explain the necessity of the circulatory system in multicellular organisms?

A) Molecules move from an area of higher concentration to an area of lower concentration.
B) Diffusion can take place in an open system or across a partition that separates two systems.
C) Diffusion is rapid over short distances but much slower over long distances.
D) Diffusion rate is inversely related to molecule size.

Question 74

Facilitated diffusion and active transport differ in that

A) facilitated diffusion uses cell membrane proteins to move substances, whereas active transport does not.
B) facilitated diffusion uses a substrate to bind to a protein carrier, whereas active transport does not.
C) ATP is necessary for active transport, but not for facilitated diffusion.
D) facilitated diffusion moves water across the cell membrane, whereas active transport does not.
E) potential energy is required for active transport but not for facilitated diffusion.

Question 75

The ability of a carrier molecule to transport only one specific molecule or a group of closely related molecules is called ________.

Question 76

Fick's law of diffusion states that the rate of diffusion across a membrane is

A) proportional to surface area and membrane thickness, but inversely proportional to concentration gradient.
B) proportional to concentration gradient, surface area, and membrane permeability.
C) proportional to membrane permeability, but inversely proportional to concentration gradient and surface area.
D) proportional to membrane thickness and surface area.

Question 77

The two extracellular compartments in the body are ________ and ________.

Question 78

The Na⁺-K⁺-ATPase pumps (this number of)________ Na⁺ ions ________ (into/out of)the cell and (this number of)________ K⁺ ions ________ (into/out of)the cell.

Question 79

Which of the following is a unique characteristic of glucose as a solute in biological systems?

A) It enters the interstitial fluid before going into the cell.
B) It is freely penetrating and can pass in and out of the cells at any time.
C) 100% of it is absorbed into the cell from the extracellular fluid.
D) It is converted into dextrose inside the cell.

Question 80

The inside of a resting cell is slightly negative relative to the outside.This is an example of

A) electrical disequilibrium.
B) osmotic equilibrium.
C) chemical disequilibrium.
D) failed homeostasis.