What is Xylem?
The Xylem is a blood vessel which transports water as well as dissolved minerals that are absorbed by root to remainder part of the plant.
The word xylem comes of the Greek word ‘xylon’ , which is a reference to wood. The most well-known tissues of xylem are located in the woody portion in the stem. If examined under a microscope, xylem tissues have an appearance reminiscent of a star. The cells that make up the tissue consist of dead cells and they are made lignified. Its cell walls are dense and composed of lignin that serves its purpose of providing support. The xylem is located at the core of vascular bundles, where the transportation of minerals and water is unidirectional. The amount of xylem present is greater than that of Phloem that is present in these bundles.
The Xylem tissues are composed of various types of cells. Tracheids, also known as trachery elements, are special, water-conducting cells that aid in transport and give physical support. The following cells are vessels that are smaller than tracheids, but aid in transport. Vessel membranes are perforated through which water as well as minerals that are dissolved are carried. Vessel elements can be found in flowering plants, where they are joined to form a continuous vessel. These elements are not in gymnosperms. Additionally, xylem has parenchyma which gives the plant with support by way of long fibers within the soft areas that make up the plants.
The earliest development of xylem begins with active root cells as well as the apical Meristem, giving rise to the primary xylem. In woody and hard plant species, the secondary xylem forms in a series of bands around the primary one when the plant grows in size. The primary xylem eventually is destroyed and ceases to perform its conductor function, but it acts as a skeleton that provides physical support. The secondary xylem will continue to perform the function of a conducting tissue that conducts water.
In mature woody plants the wood, also known as xylem is separated into sapwood and heartwood. The heart is the principal xylem that gives mechanical strength, while sapwood is the second xylem which conducts water as well as minerals. The movement of minerals and water in the xylem is an inactive process, where the energy required is not needed for the movement of the substances. The functions of xylem are replenishing the loss of water during transpiration and photosynthesis, by taking it away from the roots and giving physical support.
What is Phloem?
Phloem, a vascular organ which transports organic compounds produced during photosynthesis from green areas that the plant grows to remainder in the plants.
The word phloem originates by the Greek word ‘phloios’, which refers to bark, since the Phloem is the major component of the the plant’s bark. Phloem tissue can be found at the edges of vessels and is much less in number than the xylem tissues. Phloem, just like xylem is composed of specific cells such as sieve tube as well as the companion cell, the phloem fibres, and the phloem parenchyma. They are also living cells, and they are not being lignified. Sieve tube are columns of sieve cells with holes on the walls that the substances that feed them are transported. Phloem fibers can be described as long, flexible cells that comprise the soft fibers found in plants such as flax and hemp.
Phloem parenchyma comprises albuminous cells and companion cells that serve to help support the sieve elements and assist in the closing of the sieve tubes inside leaf veinlets. Additionally, sclerenchyma forms a type of cell that provides stiffness and support to the tissues of the phloem. It is comprised of two types of cells, cells that are sclereids or fibers. Fibers are flexible and long with a narrow lumen while sclereids are smaller irregular cells that give toughness to the tissue.
The primary phloem develops from the apical part of the shoot and root during the development stages that the plants go through. The primary phloem could be metaphloem, or protophleom. The protophloem sieve tubes cannot stretch as the tissues that extend and are destroyed as the plant grows. But, the tube cells of metaphloem develop after elongation and can therefore stay in the maturation stage to be transformed into fibers. The metaphloem’s cells serve until the secondary phloem forms in plants that have cambium. Transporting food items such as amino acids and sugar from the leaves to other organs of the plant is the main purpose that the phloem performs. The transport process in the phloem is bidirectional, meaning that food particles can travel between the tissues. It involves active processes in which energy is required to support the movement of food particles.
Difference Between Xylem and Phloem – Xylem vs Phloem
| Base for Comparative | Xylem | Phloem |
| Definition | The Xylem is a blood vessel which transports water as well as dissolved minerals that are absorbed by root to remainder part of the plant. | Phloem, a vascular organ that transports organic compounds soluble that are produced by photosynthesis from the green areas that the plant grows to remainder part of the plant. |
| Terms | The word xylem comes by the Greek word “xylon” which means wood . The most well-known xylem tissues can be located in the woody portion of the stem. | The word phloem originates of the Greek word ‘phloios’ that is a reference to bark. The phloem is the main component of the the plant’s bark. |
| Location | Xylem is found in the middle of the blood vessels. Xylem makes up the majority of the majority in the timber. | Phloem’s distribution is predominantly to the peripheral region of blood vessels. Phloem is the main majority of bark. |
| found in | The Xylem tissue is found in leaves, root and stems. | Phloem tissues can be found in leaves and stems that later develop into roots, fruits and seeds. |
| is composed of | The Xylem tissue consists of fibers, vessels, and the tracheids. | Phloem tissue consists of similar sieve tubes the phloem fibers, companion cells and phloemparenchyma. |
| Fibers | Xylem fibers are durable and long. | Phloem fibers can be flexible when shorter lengths. |
| Cells | The cells in the xylem tissue die cells, with the exception of parenchyma cells. The wall cells of cells of the xylem is thick-walled. The cell walls of the xylem are lit in the xylem. | The cells in the phloem tissues are living cells, excluding blast fibers. Cell wall in Phloem cells has a thin-walled. The cell wall isn’t lit up. |
| Quantity | The amount of xylem tissue within the bundles of vascular blood is higher than that of the phloem tissues. | The amount of phloem tissues is significantly less in vascular tissue. |
| Tyloses | Tyloses are created within the xylem. | Tylose isn’t formed within the phloem. |
| Conducive cell | Two kinds of cells that are conducive are found in xylem: vessels and tracheids. The tissues that are conducive consist of dead cells. | One type of cell that can be used to make a favorable one is found in the phloem: sieve tubes. The tissues that are conducive consist made up of cells that are living. |
| Differentiation | As plants age, xylem gets divided into sapwood and heartwood. | The same distinction is not observed in the Phloem. |
| Function | The main purpose of xylems is to transport water and minerals from the root to other areas in the plant. | The main purpose of the phloem to transfer sugars prepared through the plant’s leaves the different areas in the plant. |
| Direction | The xylem’s transport is unidirectional. Water and mineral are transported upwards from the root. | The process of transporting phloem is bidirectional, meaning that the food can be transported both in and out of the plant. |
| Support for mechanical devices | Xylem can also help in providing physical support for the plant. | Phloem does not provide the mechanical support. |
