B3 - Transpiration Rate

Question 1

List the three main things that transpiration rate is effected by.

Answer 1

increase in light intensity
Increase in temperature
Increase in air movement.

Question 2

How does an increase in light intensity affect transpiration rate?

Answer 2

The brighter the light the greater the transpiration rate

Increases the rate of photosynthesis which increases the demand for water in the leaves, also causes the stomata to open and let CO2 in to allow more water to defuse out.

Question 3

Why do stomata begin to close as it gets darker?

Answer 3

Because photosynthesis can’t happen in the dark

Question 4

How is the transpiration rate effected as it gets darker?

Answer 4

Stomata begin to close because photosynthesis can’t happen in the dark.
When the stomata are closed water can’t escape.

Question 5

How is the transpiration rate effected by an increase in temperature?

Answer 5

The warmer it is the faster transpiration happens.

Question 6

Why does an increase in temperature mean that transpiration happens faster?

Answer 6

When it’s warm water particles have maker energy to evaporate and diffuse out of the stomata.

Also increases the rate of photosynthesis and there for the demand for water.

Question 7

How is the transpiration rate affected by an increase in air movement?

Answer 7

If there is lots of air movement (wind) transpiration happens faster because the water vapour is swept away from the leaf maintaining a low concentration of water in the air outside the leaf

Diffusion happens quickly from an area of high concentration to an area of low concentration.