Transport In Plants Flashcards
(17 cards)
Where is vascular bundle found?
Roots, stem, leaves
What is found in a vascular bundle?
Xylem and phloem
What is the function of root hair cell?
Water and mineral uptake from soil
Lifespan of root hair cell
2-3 weeks
Describe the pathway from root to leaf
Water in soil > root hair > root cortex > xylem > upward movement through xylem > leaves > diffusion through stomata
What is cohesion?
Bonds formed by water when they are travelling up the stem, therefore they stick together
How does water uptake in the xylem work?
Higher water pressure at the bottom and lower water pressure at the top allows water to move up
What is transpiration?
Loss of water from plant leaves by evaporation of water at surface of mesophyll cell followed by loss of water through stomata
Steps for transpiration
- Roots absorb the water from soil
- Stem draws up the water
- Unused water evaporates
- Stomata releases water vapour
How does each factor affect transpiration rate?
- higher temp = more transpiration
- higher light intensity = more transpiration
- higher wind speed = more transpiration
- higher water supply = more transpiration
- higher humidity = less transpiration
What is a polometer?
Device used to measure/estimate transpiration
How does a polometer measure transpiration?
The distance moved by air bubble can be recorded every minute and used to indicate rate of water uptake
What is translocation?
Transport of nutrients (sucrose and amino acid)
Where is the source of translocation?
Area of production; area where photosynthesis occurs (leaf and stem)
Where is the sink of translocation?
Delivery area; area of utilisation/storage (flower, shoot, roots, fruit)
Where does translocation occur?
Phloem
Name the differences in source and sink location throughout summer, winter, and spring
Summer - sink is in the roots; source is in the leaf
Winter - none; plant is dormant and stops all chemical reactions
Spring - sink is in the shoot; source is in the roots (sucrose is used to grow new shoots)
