Transpiration And Stomata Flashcards
What is the rate of transpiration affected by
Light intensity
Temperature
Air flow
Humidity
Why does light intensity affect transpiration rate
Stomata begins to close in dark bc photosynthesis can’t happen in dark. So little water escapes through stomata in the dark
Why does temperature affect transpiration rate
Warmer means water particles have more energy to evaporate and diffuse out of stomata
Why does air flow affect transpiration rate
If there’s good air flow water outside leaf is swept away. So lower concentration so diffusion happens quickly. Opposite for bad air flow
Why does humidity affect transpiration rate
Drier the surrounding the faster transpiration happens. If the air is humid there concentration outside the leaf isn’t low enough
How can you estimate the rate of transpiration
By measuring the uptake of water by the plant. We can assume the uptake is directly related to the loss of water by the leaves
What happens to guard cells when the plant has lots of water
They fill with water and go plump and turgid, opening stomata so gas exchange can happen for photosynthesis
What happens when the plant is short of water
Guard cells go flaccid making stomata close. Helping stop too much water from escaping
Why are there more stomata on the bottom than the top
The lower surface is shaded and cooler so less water is lost.
