diffusion

Question 1

what are the 2 types of diffusion

Answer 1

simple
facilated

Question 2

why can carbon dioxide pass through the phospholipid bi layer

Answer 2

it is small and not charged therefore undergoes simple diffusion so just passes through the phospholipid bi layer

Question 3

define diffusion

Answer 3

net movement of molecules/ions from a region where they are more highly concentrated to one where their concentration is lower until they are evenly distributed

Question 4

define facilitated diffusion

Answer 4

need the help of a channel or carrier protein

Question 5

explain how a carrier protein facilitates diffusion

Answer 5

• carrier protein is specific to the molecule it binds to
• the molecule binds to a receptor on the carrier protein
• this causes a change in the shape of the carrier protein
• this causes the molecule to be released allowing it to pass through the phospholipid bilayer

Question 6

what happens to the shape of the carrier protein after the molecule is released

Answer 6

after the molecule is released the carrier protein returns to it’s original shape

Question 7

explain how a channel protein facilitates diffusion

Answer 7

• the amino acids lining the channel protein are hydrophilic
• the channel protein is filled with water
• this allows the passage of ions through the channel protein

Question 8

what happens in terms of diffusion when equilibrium is reached

Answer 8

molecules will still move back and forth