Plant Parts: The root

Plant Parts: The root
Plants are like animals and man. They have parts. Each part has it own specific function. Generally, a typical plant has three parts, these are roots, stems and leaves.

There are two kinds of root, called tap and fibrous, The tap root is a type which is made up of the main root, branching sidewise in all directions to form secondary and tertiary roots.

Most dicots have tap roots especially when these are grown from seed.
Examples of a tap root types plants are: raddish, carrots and turnips.

The fibrous type root is made up of hair-like structures of uniform sizes growing like a brush. Example of plants belonging to this type, are most monocot plants like rice, bamboo, corn and grasses.

The root is that leafless plants part which absorbs the dissolved nutrients from the soil and water. The roots also serve as anchorage, storage and reproduction organs. Sweet potato, carrots and breadfruits are examples.

The root is readily separable into epidermis, cortex and stele.

To these regions new cellars are added by an apical meristem. The outer surface of the meristem builds a root cap which protects the roots from mechanical injury as it pushes through the soil.

Cell division, elongation and maturation are progressive processes taking place at the back region of the rootcap which result in a vertical stratification of the root.

In this region successive stages in tissue differentiation are going on at the back area of elongation.

The epidermal cells produce long and cylindrical outgrowth called the root hairs, which increase the absorbing power of the root.

The cortex of the root is the same as those found in the stem. Stele is made up of strand of primary xylem and primary phloem. Roots of plants capable of marked increase on diameter develop as vascular cambium in the form of a cylinder just outside the primary xylem inside the primary phloem.

Secondary xylem is produced starting from the inner section of the cambium and secondary phloem from the outer section.

In the process of development extensive increase in diameter rupture the epidermis and cortex. At this ruptures region cork is developed either in the inner section of the cortex in the pericycle or in the area of secondary phloem.
Plant Parts: The root