Transport & Co-ordination in plants Flashcards
What is transpiration?
The evaporation of water from the plant through the stomatal pores.
What is the job of the Xylem?
Transports water & dissolved mineral ions to the leaves from the roots.
What is the job of the Phloem?
Transports dissolved sugars (sucrose) & some amino acids from the stems to the growing and storage tissues.
Where are the xylem and phloem found in the plant?
In the Vascular Bundle - Roots, Stem & Leaves
How is transpiration rates affected by temperature?
A higher temperature means more kinetic energy so diffusion is quicker.
How is transpiration rates affected by light intensity?
Light intensity being higher will dilate stomatal pores (open wider).
How is transpiration rates affected by wind speed?
High wind will blow away water vapour creating a higher concentration gradient.
How is transpiration rates affected by humidity?
High humidity will decrease the concentration gradient which will slow diffusion.
Describe how to set up a potometer:
- All will be set up under water to ensure the potometer is airtight and there is no air in it.
- Cut the stem and insert into a tube with a rubber seal.
- Measure how much water is lost in a unit time using a stopwatch and ruler.
Explain how auxin’s control growth of the shoot in response to light:
- Auxins are produced in the tip and move down the shoot
- Auxins accumulate on the side with less light
- This cause rapid cell elongation on one side
- Bending the plant towards the light
How is a root hair cell specialised for its function?
The cell has a thin cell wall –> Short distance
The root hair is long –>large Surface area
