transpiration. Flashcards
define transpiration.
movement of water from roots to leaves.
which vessels does transpiration occur in and what direction?
xylem.
moves up only.
cross section description of a xylem vessel.
no end walls between cells.
1 way only.
thick walls stiffened with lignin.
water and minerals get transported.
what are the factors that affect transpiration?
temperature.
wind speed.
light intensity.
humidity.
how does temperature affect transpiration?
increase in temp- increase rate of transpiration.
increase in temp- increase rate of evaporation from stomata.
more water loss.
how does wind speed affect transpiration?
increase in WS- increase rate of transpiration.
increase in wind removes more water vapour from surface stomata.
increase rate of evaporation from stomata.
increase lost water from plant.
how does light intensity affect transpiration?
increase in LI - increase rate of transpiration.
stomata opens wider to allow more carbon dioxide into leaf for photosynthesis.
increase rate of evaporation from stomata.
more water is lost from plant.
how does humidity affect transpiration?
increase in H- decrease rate of transpiration.
moist air surrounds stomata.
decrease rate of evaporation.
less water lost from plant.
what is each root covered in?
tiny hairs.
what do the root hair cells have that helps them absorb what?
surface area.
water and mineral ions.
what do they have that allows water to diffuse into the root more quickly?
thin cell walls.
there is a high concentration of water outside of the cell so how does water move into the cell via?
osmosis.
there is a low concentration of minerals outside of the cell so how does mineral ions move into the cell via?
active transport.
