7.7 Transport In The Xylem Flashcards
1
Q
Describe the xylem
A
No organelles
Thickened with lignin
Made of dead cells
Long hollow tubes with no end
Moves water and ions
2
Q
How does water move through the xylem?
A
Diffusion out the stomata
Tension
Cohesion- H bonds
3
Q
What conditions increase the rate of transpiration?
A
High temp
Low humidity
More stomata density
Wind speed
Light intensity
4
Q
Describe how water gets from the root hair cells to the xylem
A
Apocast pathway- (preferred pathway) through the cell walls until it gets blocked by the casparian strip
Sympathetic pathway- through cell cytoplasm( gets blocked by organelles)
5
Q
Why do xylem have dead cells,
A
To prevent water from moving into them
6
Q
What shape is lignin and why?
A
A coil shape
So it stays intact as it grows upwards
