Transpiration Rate Factors Flashcards
Name 3 factors affecting transpiration rate
- Light Intensity
- Temperature
- Air Flow
As brightness increases, what happens to the transpiration rate?
It increases
Why?
Stomata begin to close as it gets darker.
Why do stomata begin to close as it gets darker?
Photosynthesis can’t happen in the dark, so they don’t need to be open to let CO2 in. When the stomata are closed, very little water can escape.
When the temperature gets warmer, what happens to the transpiration rate?
It increases
Why?
Because when it’s warm the water particles have more energy to evaporate and diffuse out of the stomata.
When the airflow increases around a leaf, what happens to the transpiration rate?
It increases.
Why does a poor airflow result in a lower transpiration rate?
The water vapour just surrounds the leaf and doesn’t move away. This means there’s a high concentration of water particles outside the leaf as well as inside it, so diffusion doesn’t happen as quickly.
Why does a better airflow result in a higher transpiration rate?
The water vapour is swept away, maintaining a low concentration of water in the air outside the leaf. Diffusion than happens quickly, from an area of higher concentration to an area of lower concentration.
