7.7 Transport of water in the xylem Flashcards
1
Q
what is the movement of water in the plant called?
A
transpiration
2
Q
what part of the plant transports the water?
A
xylem
3
Q
how does water leave the leaf?
A
- the water evaporates from the spongy mesophyll cell
- leaves the leaf through the stomata by diffusion
4
Q
what happens in the spongy mesophyll cell once the water leaves?
A
- water is pulled from the neighbouring cells due to higher water potential in them
- thus also pulling water up from the xylem (transpiration pull)
5
Q
how is water pulled up from the xylem?
A
- water has cohesion between the molecules
- water moves up in a column
6
Q
what happens to the xylem as water moves up?
A
- diameter decreases due to the cohesion - tension theory
7
Q
what is cohesion of water?
A
the attraction of H2O to other water molecules
- due to H bonds
8
Q
what cohesion-tension theory?
A
the cohesion between the water molecules and the xylem walls
- causes tension
