3.3 Factors affecting transpiration

Question 1

increased light =

Answer 1

increased transpiration rate

Question 2

light is needed for what process?

Answer 2

photosynthesis

Question 3

during photosynthesis O2 and CO2 need to do what?

Answer 3

diffuse in and out of the plant

Question 4

through what to O2 and CO2 diffuse out of the plant?

Answer 4

open stomata

Question 5

so increased light intensity means an increased number of open what?

Answer 5

stomata

Question 6

when stomata are open what else diffuses out the plant?

Answer 6

water vapour which evaporates into the air (transpiration)

Question 7

so increased light, results in more open stomata leading to what?

Answer 7

more transpiration

Question 8

increased temperature =

Answer 8

increased transpiration rate

Question 9

the higher the temperature, what do water molecules have more of?

Answer 9

kinetic energy

Question 10

(temp) the higher the kinetic energy of water molecules result in what?

Answer 10

them evaporating from cells in the leaf faster

Question 11

(temp) faster evaporation of water increases the kPa gradient between what?

Answer 11

the inside and outside of the leaf

Question 12

(temp) the more air and increasing the kPa gradient has what effect on transpiration?

Answer 12

increased transpiration

Question 13

wind =

Answer 13

increased transpiration

Question 14

(wind) what does air movement do to water molecules?

Answer 14

blows them away

Question 15

(wind) what are water molecules trapped in?

Answer 15

a layer of still air surrounding the leaf held by hairs on the leaf surface

Question 16

(wind) the water molecules being blown away increases what?

Answer 16

the gradient in turn increasing transpiration rate

Question 17

(humidity) what is humidity?

Answer 17

the amount of water vapour in the air

Question 18

the lower the humidity =

Answer 18

the faster the transpiration rate

Question 19

if there is low humidity and the area around the plant is dry what happens to the water potential gradient?

Answer 19

it is increased, increasing transpiration rate

Question 20

the drier the soil, the less water available for the plant - how does this affect transpiration rate?

Answer 20

transpiration rate reduced