What is the root?It is a very important organ of the plant, ensuring its growth and livelihoods.The emergence of this body have been linked to the stage of development of the earth's surface flora.
root - is the underground part of the plant, which has apical growth and has a radial structure.
main functions of the root are:
- anchor - that is, hold the plant in the soil;
- and absorbent - getting out of the ground water and mineral substances transported through the xylem (water conducting tissue) to all above-ground parts of the plant for the production process of photosynthesis.
Also synthesized in the aerial parts organic substances and at the root of hormones, amino acids, alkaloids, et al., And accumulated therein are supply of nutrients.The root is also an organ of vegetative propagation of plants.
Along with the definition of what is the root, always appears the concept of the root system, which is formed by all the roots of the plants in the aggregate.There are main, subordinate, and lateral roots.
main (or primary) gets its roots still in the embryonic development of the spine.In flowering plants and gymnosperms is the main taproot, has unlimited growth and positive geotropism (ie giving the correct direction for the growth of plants).
Adventitious roots are secondary and grow from the stems, leaves or roots of old.
Lateral roots grow from the main and paranasal.
root systems of its type are core or fibrous.At the core of the root system of the primary root is strongly expressed.This system has a predominantly dicotyledonous plants (eg, carrots, dandelion, watermelon, sunflower).When fibrous root system growth of the main root of the little pronounced, it does not stand out among the adventitious roots (such as valerian root, plantain, rye).This root system is typical for mainly monocots.
internal structure of roots
What is the root, in terms of its internal structure?At its center is conducting a root system consisting of sieve tubes and vessels.The vessels provide transportation of water, along with dissolved nutrients to the aerial parts of the plant by the root hairs.Sieve tubes, on the contrary, is transported from organic solutions of ground root cells.Cells educational root tissue (cambium) continually divide and ensure that the growth of roots in thickness.
What is the root, and all of its main areas are clearly visible in the longitudinal section.
root cap is formed by a cover with a cloth and cover the top of the root, protecting it as a cap from various injuries.Another of his function is to promote the advancement of the root in the ground.
Zone division is located immediately below the root cap and consists of small cells educational fabric that its permanent division provides root growth.
area stretching formed very young, but growing cells, extends in the longitudinal direction and thereby engaged in root growth in length.
If the plant carefully dig, you can see how the roots entwine soil particles, this part is called the zone of absorption.It is covered with root hairs, which is a function of the absorption of water and nutrients.Hairs are slime surface.
above the suction zone is a zone of the formed conductive fabric and make up a large part of the length of the root.For vessels root upwards along the stem moving water and minerals which are dissolved in it immediately.
Some plant roots can be altered by the emergence of unfavorable conditions for plant growth and to ensure adaptation.
