Lecture 4: Diffusion vs. Bulk Flow

Question 1

diffusion

Answer 1

water movement during transpiration

Question 2

transpiration

Answer 2

evaporation of water mainly through the stomata of the leaves

Question 3

stoma

Answer 3

1 pore of a stomata

Question 4

what are the different ways of water movement in the plant

Answer 4

1. osmosis
2. bulk flow
3. diffusion

Question 5

what does Fick’s law describe

Answer 5

the movement of water by diffusion

Question 6

diffusion rate is affected by:

Answer 6

area distance, and gradient

Question 7

how does area affect diffusion rates

Answer 7

larger area = move efficient diffusion rates

Question 8

adaxial

Answer 8

above/top part of leaf

Question 9

abaxial

Answer 9

Back/underneath part of leaf

Question 10

what are some important compounds of the cell wall

Answer 10

pectin, cellulose, microfibrils

Question 11

the cell wall is covered by a _____ film

Answer 11

water

Question 12

why is surface tension stronger than cohesion

Answer 12

the water on the surface have no H2O above, making attraction forces stronger on their nearest neighbors on the surface

Question 13

what does the air water interface look like when the stomata is closed and the water pressure is 0

Answer 13

it is flat with tension

Question 14

what does the evaporation and condensation rates look like when the stomata is closed and the water pressure = 0

Answer 14

they are the same (at equilibrium)

Question 15

what does the air-water interface look like when the stomata is open and the water potential is less than 0

Answer 15

it becomes curved with tension trying to pull it back up (like when jumping on trampoline)

Question 16

what does the evaporation and condensation rates look like when the stomata is open and the water pressure is less than 0

Answer 16

evaporation is higher than condensation