<P> Meristematic cells are incompletely or not at all differentiated, and are capable of continued cellular division (youthful). Furthermore, the cells are small and protoplasm fills the cell completely . The vacuoles are extremely small . The cytoplasm does not contain differentiated plastids (chloroplasts or chromoplasts), although they are present in rudimentary form (proplastids). Meristematic cells are packed closely together without intercellular cavities . The cell wall is a very thin primary cell wall . </P> <P> Maintenance of the cells requires a balance between two antagonistic processes: organ initiation and stem cell population renewal . </P> <P> Apical meristems are the completely undifferentiated (indeterminate) meristems in a plant . These differentiate into three kinds of primary meristems . The primary meristems in turn produce the two secondary meristem types . These secondary meristems are also known as lateral meristems because they are involved in lateral growth . </P> <P> At the meristem summit, there is a small group of slowly dividing cells, which is commonly called the central zone . Cells of this zone have a stem cell function and are essential for meristem maintenance . The proliferation and growth rates at the meristem summit usually differ considerably from those at the periphery.It also helps In the growth of the plant . </P>

What is meristem and its role in plants