Topic 8 Flashcards
What are the two transport systems
Xylem
Phloem
Xylem function
Transports water and mineral ions. The roots absorb the water and mineral ions from the soil. These enter the xylem in the root and travel upwards in the stem
What is the phloem
Transports sucrose,amino acids and hormones throughout the plant.
What is sucrose
A soluble complex sugar made especially for transporting energy it is made in leaves with the sugars from photosynthesis and from starch in storage organs such as swollen roots and stems
How are substances transported in the phloem
Downwards from the leaves to roots and upwards from leaves to flowers and from stems tocleaves
Root hair function
Absorb water and mineral ions
Cortex function
Stores some food as starch
Phloem function in root
Transports sucrose and amino acids from the leaves which make new cells at the root tip
Xylem function in root
Transports water and ions up the root
Xylem function in stem
Transports water and mineral ions up to the leaves
Phloem functions
Transports sucrose and amino acids down to the roots and up to the flowers and fruits
Water uptake by roots
The main functions of roots are to anchor the plant in the soil and to take up water and mineral ions. Water passes into the root by osmosis
What is transpiration
The loss of water vapor from plant leaves
Wilting meaning
The Stomata close up to reduce transpiration. If the plant still does not get enough water it will start to wilt. The cells have lost so much water they can no longer be (turgid) full of water
Factors affecting transpiration
The rate of transpiration increases as the the air temperature increases
The rate of transpiration increases as the wind speed increases
