Meaning of Xylem
What is Xylem:
Xylem is a woody tissue of metaphytic plants formed by vessels, parenchyma and fibers through which the ascending sap circulates. The term xylem is of Greek origin "xylon" What does it mean "wood”.
The main function of the xylem is to transport water, mineral salts and other nutrients from the roots to the leaves of the plants. Likewise, the secondary function of the xylem is the reserve of minerals and support or support.
The xylem uses 2 forms of energies in order to transport the raw sap from the root to the leaves, firstly, the phenomenon of osmosis is observed, it displaces the accumulated water upwards, product of the difference in the soluble power of the root tissue and the soil moisture and, finally, the phenomenon of suction attracts the water contained in the vascular tissue to the leaves.
The xylem is formed by a primary xylem that encompasses the growth points of stems and roots, secondary xylem located between the xylem and the phloem and, new xylem cells can originate towards the inside of the roots and outside in almost all the stems.
Likewise, the xylem contains conductive elements such as: xylem vessels and tracheids, as its name indicates, it is responsible for transporting, in turn, non-conductive elements such as: axial and radiomedullary parenchyma, and sclerenchymal fibers. Tracheids are elongated cells with thick walls determined in thin areas known as puteaduras, characterized by vessels and fibers, the latter perform the transport function and increase the mechanical resistance of the xylem.
In 1837 the term was proposed in German as "xylem" by the Swiss botanist Karl Wilhelm von Nageli, from German it became English and Spanish as xylem, as we know it today.
Xylem and Phloem
Phloem is a term of Greek origin "Phloos"Which means" bark ". Phloem is a conductive tissue that is responsible for transporting organic and inorganic nutrients, especially sugars.
The elements that make up the phloem are: sieve elements, their function is to facilitate transport by apoplast and the parenchymal cells are responsible for loading and unloading the sieving elements, transporting the sugar to accompanying cells.
Similarly, 2 types of phloem are observed: primary phloem and secondary phloem. The primary phloem is associated with the primary xylem composing the vascular bundles and the secondary phloem located on the periphery of the stem and root.