Xylem and Phloem are the transport tissues in vascular plants and are responsible for transport of water, nutrients, etc. throughout different parts of the plants. Xylem is also responsible for providing mechanical strength to the plant and tissue. The chief role of xylem is to transport water and water soluble nutrients from roots to all the parts of the plant. This transport takes place through capillary action. Due to transpiration (loss of water or moisture from leaves), a suction is created. This provides enough pull for the water in the root zone to be transported to the leaves (and other organs) through capillary action. Apart from the suction of transpiration, water can also be pulled into the roots by osmosis, from the neighboring soils. The water transport takes place through narrow vessels and xylem is perfectly capable of transporting water through these narrow channels, even for very tall trees, that is the height of the capillary column can be very large. The most common example of xylem is wood.
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The Xylem is one of the two kinds of transport tissues utilized in vascular plants. The other way of transport is the phloem. The most famous and well known xylem tissue in the world is wood. The fundamental function of xylem is to transport water however, it will also transport various types of nutrients. Specifically the Xylem's main job is to transport water upward throughout the plant starting from the roots.