Diffusion

Question 1

what is diffusion?

Answer 1

the net movement of substances from a high to low concetration down a concetration gradient

Question 2

what kind of movement happens in diffusion?

Answer 2

a net movement

Question 3

what must simple diffusion substances be?

Answer 3

lipid-soluble (dissolves through lipids), small (e.g. o2 & Co2), non-polar(has no separation of charge), uncharge

Question 4

what is Fick’s law?

Answer 4

certain factors affecting rate of diffusion
rate of diffusion = surface area x concetnration gradient / thickness of membrane
the rate of diffusion is proportional to surface area X concentration gradient/ thickness of membrane

Question 5

what else is the rate of diffusion affected by?

Answer 5

temperature

Question 6

what does facilitated diffusion involve using?

Answer 6

carrier proteins & protein channels

Question 7

when is facilitated diffusion required?

Answer 7

if a molecule is water-soluble, large, polar or charged (an ion)

Question 8

how do carrier proteins help with diffusion?

Answer 8

molecule enters specific carrier proteins and bind to it, causes carrier protein to change shape, molecule then released from carrier proteins on the other side of membranes.

Question 9

what do protein channels do for diffusion?

Answer 9

protein channels create hydropilic pore in the membrane, soluble ions pass through

Question 10

what happens if theres more carrier proteins or protein channels in a membrane?

Answer 10

the greater the rate of facilitated diffusion