Question

Phloem is active in all directions within a cell. How does its components helps to do its functions?

Answer 1

Dear student
The Phloem is composed of a variety cells . These are in angiosperms 1) sieve tube element 2) companion cells elements 3) phloem fibres 4) phloem parenchyma . Gymnosperms have albuminous cells and sieve cells.
Function in angiosperms :
1) sieve tube element : The main function is to translocate the organic solute.
2) companion cells : Its function is not specified ,although it appears to load and unload the sugar into sieve element.
3)phloem fibres:The main function is mechanical support.
4)phloem parenchyma:The main function are storage and translocation of food.
Function in gymnosperms :
1) Albuminous cells have similar function to companion cells, found only in seedless plants.
2)Sieve cells have pores which allow nutrients to pass from cell to cell, no sieve plates present like sieve tube elements.
Regard