Ch4 Movement of substances

Question 1

Diffusion

Answer 1

net movement of molecules from an area of high concentration to an area of low concentration until an equilibrium is reached

Question 2

Simple diffusion

Answer 2

1. passive process
2. move through phospholipid bilayer
3. energy from kinetic movement

Question 3

Facilitated diffusion

Answer 3

1. passive process
2. move through carrier and channel proteins

Question 4

Osmosis

Answer 4

passage of water from region where it has a higher wpt to an area of lower wpt through a selectively permeable membrane

Question 5

Fick’s law

Answer 5

(SA x concentration gradient) / diffusion pathway

Question 6

Lower wpt

Answer 6

1. addition of solute to pure water reduces wpt
2. decreases form 0KPa

Question 7

Surround red blood cells with pure water

Answer 7

1. water enters by osmosis
2. cell surface breaks
3. swells and bursts- haemolysis

Question 8

Surround red blood cell with concentrated solute solution

Answer 8

1. water leaves by osmosis
2. cell shrinks and shrivels

Question 9

Surround plant cell with pure water

Answer 9

1. water enters by osmosis
2. swells
3. cell wall prevents from bursting
4. becomes turgid

Question 10

Surround plant cell with concentrated solute solution

Answer 10

1. water leaves by osmosis
2. cell wall prevents shrinking
3. protoplast shrinks
4. plasmolysis

Question 11

Active transport

Answer 11

movement of molecules from a region of lower concentration to a region of higher concentration using ATP and carrier proteins

Question 12

Active transport differences

Answer 12

1. ATP is needed
2. moves against concentration gradient
3. uses carrier proteins
4. selective

Question 13

Process of active transport

Answer 13

1. molecules bind to carrier protein
2. ATP hydrolysed to ADP+Pi
3. energy causes carrier protein to change shape
4. carrier protein releases molecule to other side
5. carrier protein releases Pi to return to original shape