chapter 4 questions

facilitated diffusion differs from simple diffusion in what way? a. the rate of facilitated diffusion depends on the number of carriers in the membrane b. transport does not require energy c. the rate of facilitated diffusion is dependent on the concentration gradient of the transported molecule d. the direction of transport is against the electrochemical gradient

a

at an ion's equilibrium potential, the chemical driving force on that ion is __________________ the electrical driving force. a. greater than b. equal to c. less than

b

if a sodium ion is attracted to the inside of a cell, _____________________ a. there must be more sodium ions inside the cell than outside b. the extracellular fluid must be more negative than the intracellular fluid c. there must be a next excess of negative charges inside the cell with respect to the outside d. none of the above

c

Oxygen diffuses from blood into cells down its concentration gradient. As cells become more active and oxidative phosphorylation increases in the cell, which of the following occurs? a. concentration gradient for oxygen decreases and oxygen movement into the cell decreases b. concentration gradient for oxygen increases and oxygen movement into the cell decreases c. concentration gradient for oxygen decreases and oxygen movement into the cell increases d. the concentration gradient for oxygen increases and oxygen movement into the cell increases

d

the rate of diffusion, or flux, of particles across a membrane is dependent upon __________________ a. the surface area of the membrane b. the membrane permeability c. the steepness of the concentration gradient across the membrane d. all of the above

d

transport processes that can be saturated include ___________________ a. secondary active transport b. movement of ions through some channels c. facilitated diffusion d. primary active transport e. all of the above

e

transport processes that require an energy source include ________________ a. primary active transport b. secondary active transport c. facilitated diffusion d. movement of ions through channel pores e. answers a and b f. answers a, b, and c

e

which of the following statements about facilitated diffusion is (are) true? a. The net diffusion of solutes utilizing facilitated diffusion can never be zero. b. The rate of facilitated diffusion is directly dependent on the affinity of the solute for the carrier protein. c. The rate of facilitated diffusion is directly dependent on the concentration gradient of the solute across the membrane. d. a and b e. b and c f. all of the answers above are correct

e

which of the following transport mechanisms may be utilized to move glucose across cell membrane? a. primary active transport b. secondary active transport c. facilitated diffusion d. simple diffusion e. b and c f. a, b, and c

e

an increase in which of the following would increase the rate of diffusion of oxygen molecules across pulmonary cell membranes? a. membrane thickness b. membrane surface area c. the oxygen concentration inside the lung d. temperature e. a and b f. b, c, and d

f

Comparing intracellular to extracellular fluid, the intracellular fluid has a ________ charge relative to the outside of a cell due to the presence of more ________ in that solution

negative, anion

proteins that perform primary active transport are both transport proteins and enzymes t/f

t

the direction molecules are transported across the cell membrane refers to the net movement of those molecules t/f

t