Vascular Tissue in Plants

Vascular tissue is a complex type of tissue found in plants, which allows nutrients and water to be transported throughout the plant via two main transporting tissues – the phloem and the xylem. This conduction of water and nutrients enables plants to grow healthily with all parts receiving the necessary resources whenever they need them. The phloem and xylem transport different substances, with some degree of overlap between the two tissues. The phloem is a type of living tissue that is mainly responsible for transporting organic substances that are produced during photosynthesis, such as sugar, to the parts of the plant where the substance is required.

The xylem on the other hand, mostly transports water to the parts of the plant requiring this substance, but may also transport some nutrients from time to time. The xylem draws the water and nutrients from the roots to the upper parts of the plant body. These conductive tissues are shaped like pipes for ease of transport, and new cells sometimes adjoin to old cells in a lengthwise fashion to allow substances to be properly transported to the correct destination. The vascular tissue is arranged in long, discrete strands called vascular bundles. Between the xylem and phloem is a meristem, tissue consisting of undifferentiated cells, called the vascular cambium. This undifferentiated tissue divides off cells that will be become additional xylem and phloem. This growth increases the girth of the plant, rather than its length. As long as the vascular cambium continues to produce new cells, the plant will continue to grow wider.

The efficiency of the conductivity of the water and nutrients depends on several necessary processes involving water in the plant. These processes include absorption, transpiration and conduction of water. If there is too little water in the plant, then the nutrients and other substances wouldn’t be properly transported to the required destination.  Water is absorbed via the roots and leaves the plant via the stomata on its leaves. All the water molecules are attached to other water molecules via hydrogen bonds. As each molecule of water evaporates, another one moves into place to replace it, moving the line of bonding water molecules up in line thanks to the structure of the phloem and xylem of the vascular tissues. This in turn allows other nutrients and substances to be transported efficiently.

These conductive abilities of vascular tissues allow plants with these tissues to grow to large sizes, as opposed to plants without this capability. This is essential so that plant tissue is able to survive and maintain strong and steady growth, and continue to seed.