TRANSLOCATION Flashcards
1
Q
PITS
A
- Allow water to move laterally, in, out and between vessels
- Helpful used there’s a blockage in xylem
- Provides an alternative pathway for water to travel
2
Q
APOPLAST PATHWAY
A
- Via cell walls
- Blocked at endodermis by the casparian strip
3
Q
SYMPLAST PATHWAY
A
Cytoplasm
4
Q
POTOMETER SET- UP
A
- Cut shoot underwater - no bubbles
- Apply Vaseline to tips of shoots - no bubbles
- Air tight
5
Q
Why would you replicate an experiments three times and calculate a mean?
A
- To identify anomalies
- More reliable
6
Q
Why do potometers only give estimates?
A
- Actually measures water uptake
- Not all water is lost - used for photosynthesis
7
Q
TRANSPIRATION
A
The loss of water vapour by diffusion through the stomata of plant leaves.
8
Q
LIGNIN
A
- Makes xylem walls lignified and waterproof
- Improves cohesion and adhesion
- Strengthens the plant/xylem wall
- So prevents stem from breaking
9
Q
STAGE 1
A
• Hydrogen ions move out of companion cells by active transport.
10
Q
STAGE 2
A
- This creates a concentration gradient
- Hydrogen ions are able to diffuse back into companion cell
- Cotransport protein acts as a carrier for both hydrogen ions and sucrose
11
Q
STAGE 3
A
• Sucrose molecules move from companion cell into the sieve tubes through plasmodesmata
