Xylem vs Phloem
Similarities and Differences between Xylem and Phloem
Xylem and Phloem are the components of the vascular tissue system in plants. In the young parts of the stem, the xylem and phloem are together organized as vascular bundles. Both xylem and phloem are complex tissues which composed of more than one types of cells. The present post describes the similarities and differences between Xylem and Phloem.
Similarities between Xylem and Phloem
Ø Both xylem and phloem are complex tissue composed of more than one type of cells.
Ø Both are the components of vascular tissue system of plants.
Ø Both contain living and dead cells.
Ø Both contain parenchymatous cells.
Ø Both contain fibres.
Ø In primary vascular bundles both xylem and phloem are differentiated into proto- and meta- elements.
Ø Both shows primary and secondary growth.
Ø Both xylem and phloem are developed from the cambium.
Ø Both the term ‘xylem’ and ‘phlolem’ are proposed for the first time by Carl Wilhelm von Nägeli
Difference between Xylem and Phloem
|1||The term derived from a Greek word “xylon’ meaning wood||The term derived from a Greek word ‘phloios’ meaning bark|
|2||Composed of vessels, tracheids, parenchyma and fibres.||Composed of sieve elements (sieve cells or sieve tubes), companion cells, parenchyma and fibres.|
|3||Consists of mainly dead cells (only parenchyma is the living cells in the xylem).||Consists mainly of living cells (only fibres are the dead cells in the phloem).|
|4||Conduct water and minerals.||Conduct food materials.|
|5||Can provide mechanical support.||Cannot provide mechanical support.|
|6||Amount of xylem is more than that of phloem.||Amount of phloem is less than that of xylem.|
|7||Tyloses formation occurs in the xylem||Tyloses formation do not occur in the phloem.|
|8||Transport through xylem is unidirectional.||Transport through phloem is bidirectional.|
|9||Xylem occupies inner to the vascular cambium.||Phloem occupies outer to the vascular cambium.|
|10||The conductive tissue in the xylem is dead (Tracheids and Vessels).||The conductive tissue in the phloem is living (Sieve elements).|
|11||Contain two types of conductive cells (Tracheids and Vessels).||Contain only one type of conductive cells (Sieve elements).|
|12||Majority of the cells in the xylem are thick walled cells.||Majority of the cells in the phloem are thin walled cells|
|13||Xylem fibres are usually smaller.||Phloem fibres are usually larger called bast fibres.|
|14||In mature plants, the xylem forms the major bulk of the plant body.||In mature plants, the phloem forms the major bulk of the bark.|
|15||In mature plants, the wood (xylem) is differentiated into heart wood and sap wood.||No such differentiation of phloem occurs.|