Parenchyma is the most versatile of all types of tissues. They are capable of division and growth. However, development of a tissue is characterized by 3 types of cell growth: cell division, cell elongation and cell differentiation. For this purpose, the explant from healthy and young part of the plant is used. Presence of parenchyma is first consideration in a particular species. Parenchyma from stems, rhizomes, tubers, roots is easily accessible and will generally respond quickly to culture conditions
There are a variety of forms of seed plants viz., trees, herbs, grasses, which exhibit the basic morphological units i.e.
root, stem and leaves. These again vary with differences in cells and tissues, and their topography.