Transpiration And Translocation Flashcards
Transpiration
Loss of water from a plant
What is transpiration caused by?
Evaporation and diffusion of water from a plant’s surface
Where does transpiration happen most?
Leaves
Evaporation creates a slight shortage of water in the leaf, so what happens?
More water is drawn up from the rest of the plant through the xylem vessels to replace it
More water drawn up from the roots - so constant transpiration stream of water through the plant
What is the rate of transpiration affected by?
Light intensity
Temperature
Air flow
Humidity
Light intensity
Brighter the light, greater transpiration rate
As it gets darker, stomata begin to close - photosynthesis can’t happen in the dark
Temperature
Warmer it is, faster the rate of transpiration happens
When its warm, water particles gave more energy to evaporate and diffuse out of the stomata
Air flow
Better the air flow, greater the transpiration rate
Humidity
Drier the leaf, faster transpiration happens
How can you estimate the rate of transpiration?
By measuring the uptake of water
What do guard cells do?
Open and close the stomata
Translocation
Transport of substances in both directions
