We know seeds give rise to seedlings, from seedlings there develops a large plant. The plant produces flowers and fruits. These are all the results of growth and development of the plant. The embryo is present in the seed. The growth of embryo is the germination. So without the growth of embryo germination of seed will not take place. Without germination, seedlings will not produce. Without the growth of seedlings, a large plant will not develop. Without the development of a large tree, we shall not get flowers, fruits, seeds, wood, crops, or the forest and nothing of this sorts.
So growth and development of the plant are essential for them so that they can again produce seed to maintain their growing by reproduction. Again the growth and development of the plant are essential for all animals including human beings because with growth and development of plant we will not get anything like – food, medicine, clothes, house building materials and a habitable environment. Growth is a fundamental characteristic of all living organisms. Growth means a permanent increase in shape, size weight and in bulk of a plant or its organ.
The region of Growth: The ideal growing region of plants is its root and shoot apex. In root or shoot apex there are apical meristems. This region is also known as the primary meristematic region or primary growth region.
Growth in length: The apical Meristematic tissue by successive cell division creates new cells. The new cells, later on, increase in size. In this way by the formation of new cells and their increase in size, the apical parts successively increase in length. Formation of young leaf and bud is also the function of these tissues.
At the top of the root there present a cover like structure, which is called root cap. The cell division region is behind the root cap region. The cell of this region divide rapidly and forms many new cells. Behind the cell division region of elongation. Cells of this region increase in size and volume especially in length, as a result, length of root increase. Behind the region of elongation lies the permanent region. Cells of this region are mature and are different in shape and size.
At the top of the stein, there is a bud called apical bud or shoot apex. Cells of apical bud are meristamatic cells. Therefore this is the cell division region because cells of this region divide rapidly and increase in number. Behind this region is the region of elongation, as cells of this region rapidly increase in length. Behind this region is the permanent region, cells of this region is mature and are different in shape and size.