3.3.4 The Phloem

Question 1

Phloem Structure

Answer 1

The function of the phloem tissue in plant is to:
- transports organic compounds (assimilates), particularly sucrose, from the source (e.g. leaf) to the sink (e.g. roots)
- the transport of these compounds can occur up and down the plant
The organic compounds are dissolved in water to form sap
Phloem is a complex tissue made up of various cell types
- its bulk is made up of sieve tube elements which are the main conducting cells and companion cells
Other cells types of phloem tissue also include parenchyma for storage and strengthening fibres
Mature phloem tissue contains living cells, unlike xylem tissue