Physiology - Ch. 5 Membrane Dynamics

3) Which body fluid compartment contains higher levels of Na+, Cl-, and HCO3-? A) plasma B) interstitial fluid C) intracellular fluid D) A and C E) A and B

A and B

22) Caveolae and clathrin-coated pits are both used in A) endocytosis. B) exocytosis. C) phagocytosis. D) all of the above E) none of the above

Endocytosis

79) Water will always move from __________ areas to __________ areas, if there are no impermeable barriers. A) hyperosmotic, hyposmotic B) hyposmotic, hyperosmotic C) hyposmotic, isosmotic D) hyperosmotic, isosmotic

Hyposmotic, hyperosmotic

21) 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.

Negatively charged

28) 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) A and B E) A, B, and C

A and B

12) 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.

A group of carrier proteins is operating at its maximum rate

10) The term cellular (metabolic) energy indicates any biological process requiring A) energy in any form. B) ATP. C) thermal energy. D) chemical energy. E) C and D

ATP

78) 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) energy is required for active transport but not for facilitated diffusion

ATP is necessary for active transport, but not for facilitated diffusion

119) The concentration of calcium inside a cell is 0.3%. The concentration of calcium outside the cell is 0.1%. How could the cell transport even more calcium to the inside? A) passive transport B) active transport C) osmosis D) exocytosis E) all of the above

Active transport

27) 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 above E) none of the above

All of the above

81) Which of the following molecules can move across the phospholipid bilayer by simple diffusion? A) lipids B) steroids C) water D) A and C E) all of the above

All of the above

85) Cations will __________ anions. A) attract B) repel C) not react with

Attract

72) 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.

Can change which substances pass through by changing its lipid and protein content

75) 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.

Chemical disequilibrium

76) 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.

Chemical disequilibrium

23) As the charge on the membrane of a typical neuron approaches 0 from -70 mV, the cell is A) repolarizing. B) hyperpolarizing. C) depolarizing. D) becoming more difficult to stimulate. E) B and D

Depolarizing

77) 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.

Diffusion is rapid over short distances but much slower over long distances

86) The cell membrane acts as a good A) electrical insulator. B) electrical conductor. C) electrical gradient. D) source of ions.

Electrical insulator

74) Pinocytosis and potocytosis are types of A) endocytosis. B) exocytosis. C) phagocytosis. D) A and B E) B and C

Endocytosis

13) 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.

Exocytosis

14) 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) facilitated diffusion B) osmosis C) active transport D) A and B E) none of the above

Facilitated Diffusion

117) If a 10% sucrose solution is separated from a 20% sucrose solution by a membrane impermeable to sucrose, in which direction will net movement of water occur? A) from the 10% sucrose solution to the 20% sucrose solution B) from the 20% sucrose solution to the 10% sucrose solution C) There will be no net movement of water in this case. D) A and B E) none of the above

From the 10% sucrose solution to the 20% sucrose solution

118) If a 10% sucrose solution is separated from a 20% sucrose solution by a membrane permeable to sucrose, in which direction will net diffusion of sucrose take place? A) from the 10% sucrose solution to the 20% sucrose solution B) from the 20% sucrose solution to the 10% sucrose solution C) There will be no diffusion in this case. D) A and B E) neither A nor B

From the 20% sucrose solution to the 10% sucrose solution

16) 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 above

Have a lower concentration of solutes than hyperosmotic solutions

80) 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.

Hydrophilic and lipophobic

2) Which body fluid compartment contains high levels of K+, large anions, and proteins? A) plasma B) interstitial fluid C) intracellular fluid D) A and C E) A and B

Intracellular fluid

18) 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.

It results, in part, from the concentration gradients for Na+ and K+

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.

It transports Na+ and K+ in a 1:1 ratio

9) Permeability is a property of A) membranes. B) ions. C) solutes. D) solvents. E) proteins.

Membranes

15) In an epithelium, the apical membrane is also known as the __________ membrane. A) basolateral B) mucosal C) serosal D) basement E) nictitating

Mucosal

24) The ion that plays a key role in initiating electrical signals in neurons is A) K+. B) Na+. C) Cl-. D) Ca2+.

Na+

4) A living body is electrically A) neutral. B) positive. C) negative

Neutral

26) 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.

No cellular energy

11) 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 above

Plasma and interstitial

7) Bulk flow is fluid flow as a result of a __________ gradient. A) concentration B) electrical C) pressure D) two of the above E) none of the above

Pressure

73) 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.

Proportional to concentration gradient, surface area, and membrane permeability

83) Cations will __________ each other. A) attract B) repel C) not react with

Repel

84) Anions will __________ each other. A) attract B) repel C) not react with

Repel

25) 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 E) The interior of the cell membrane has an excess of negatively charged protein

Resting membrane permeability for sodium ions greater than potassium ions

6) 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

Simple diffusion

8) 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

Simple diffusion

5) Which of the following does NOT influence membrane permeability? A) the size of the diffusing molecule B) the thickness of the lipid bilayer C) the lipid solubility of the diffusing molecule D) the composition of the lipid bilayer

The thickness of the lipid bilayer

82) A cell that is permeable to Solute X is placed into solution containing a higher concentration of X. Diffusion occurs until equilibrium is attained. At this time A) there is no further movement of Solute X across the membrane. B) there is no further change in concentration of Solute X. C) both A and B D) neither A nor B

There is no further change in concentration of Solute X

1) Using CO2 as an example, which of the following summarizes the Law of Mass Balance? A) total load of CO2 in body = intake + metabolism + production - excretion B) total load of CO2 in body = intake + production - excretion - metabolism C) total load of CO2 in body = intake - production - excretion - metabolism D) total load of CO2 in body = intake + production - excretion + metabolism E) total load of CO2 in body = intake - production - excretion + meta

Total load of CO2 in body = intake + production - excretion - metabolism

19) Voltage-gated (voltage-dependent) channels and antiport carriers are both types of A) structural proteins. B) enzymes. C) transporters. D) receptors.

Transporters

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.

-70 mV