Passive Transport & Diffusion

Question 1

cells are ____ systems

Answer 1

open

Question 2

____ ________ serve as barriers & gatekeepers

Answer 2

cell membranes

Question 3

the ______ ____ of the membrane is the main barrier to movement across the membrane

Answer 3

hydrophobic core

Question 4

the ability of a substance to cross a cell membrane depends on ________ _______ and ________ _______ _______

Answer 4

phospholipid permeability; integral membrane proteins

Question 5

diffusion of substances across a membrane

Answer 5

passive transport (simple diffusion)

Question 6

diffusion of a solute across a membrane w/ the help of a transport protein

Answer 6

facilitated diffusion

Question 7

movement of a solute from a region of low concentration to high concentration; requires energy input & a transport protein

Answer 7

active transport

Question 8

the process of random movement toward equilibrium

Answer 8

diffusion

Question 9

______ occurs when particles continue to move, but there is not net change in distribution

Answer 9

equilibrium

Question 10

diffusion always occurs from a region of ____ concentration to a region of ___ concentration

Answer 10

high; low

Question 11

diffusion leads to a ________ distribution of solutes

Answer 11

uniform

Question 12

_______ transport does not require energy

Answer 12

passive