Transpiration Flashcards
1
Q
What is transpiration?
A
the loss of water by evaporation from the leaves
the movement of water from the roots to the leaves (transpiration stream)
2
Q
Describe the journey of water through a plant.
A
- water enters the roots by osmosis/diffusion
- water drawn up the stem through the xylem from the roots
- water drawn into leaf cells from the xylem
- water vapour evaporates from leaves through the stomata
3
Q
How do guard cells work?
A
- guard cells are open when they take in water by osmosis and swell up
- when they lose water they become flaccid and the stoma closes
(the cell wall is thicker on the inside of the cell)
4
Q
How are water molecules pulled up the xylem vessels?
A
by weak forces of attraction between the molecules
