Anatomy & Physiology Ch. 3 ( Cell Transport)

Front 1

selective permeability
or
semipermeable

Back 1

membrane is a barrier allowing some substances to pass through more readily than others

Front 2

lipid bilayer permeability

Back 2

permeable to nonn-polar uncharged molecules (0,C02, steroids)
slightly permeable to H2O & urea (leak through as lipids flip-flop)
channels & transporters provide selective permeability

Front 3

2 criterion used to classify transport processes

Back 3

1) mediation
2) Energy used (active/passive)

Front 4

mediated transport

Back 4

involves assistance of a transporter protein

Front 5

non-mediated transport

Back 5

does not require a transporter protein
(lipid layer/channel diffusion)

Front 6

Active transport

Back 6

needs additional energy (usually ATP) to move up a concentration gradient

Front 7

Passive transport

Back 7

uses chemical's kinetic energy to move down a concentration gradient

Front 8

concentration gradient

Back 8

the difference in the concentration of a chemical from one place or another

Front 9

electrical gradient

Back 9

the difference in electrical charges in two regions;
it occurs across the plasma membrane so it is termed
MEMBRANE POTENTIAL

Front 10

electrochemical gradient

Back 10

combined influence of concentation gradient and membrane potential

Front 11

diffusion
(in a solution)

Back 11

passive process
random mixing of particles in a solution
solute moves down it's concentration gradient in the solvent
until equilibrium is reached

Front 12

solute

Back 12

dissolved substance

Front 13

solvent

Back 13

liquid that does the dissolving

Front 14

equilibrium

Back 14

particles are evenly distributed in the solution

Front 15

Laws of Diffusion

(factors that influence diffusion across a membrane)

Back 15

1) steepness of concentration gradient
2) temperature
3) mass of the diffusing substance
4) surface area
5) diffusion distance