Types discussion: Autism (a developmental brain disorder characterized by impaired social interaction and communication skills, and limited range of activities and interests) is the most characteristic and best studied PDD.
A meristem is the tissue in most plants containing undifferentiated cells (meristematic cells), found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of the plant and keep the plant growing.hese secondary meristems are also known as lateral meristems because they are involved in lateral growth. At the meristem summit, there is a small group of slowly dividing cells, which is commonly called the central zone.
Meristems are the specific sites in the plant where mitotic divisions produce new cells. Most plants grow from the tips of branches and roots where apical meristems produce new cells. As a result, in all buds, at the ends of all branch tips and on root tips, apical meristems are found.Apical meristems produce new cells that differentiate into three distinct embryonic tissues.These are the protoderm, ground meristem, and procambium. In the diagram, you can see protoderm will form the epidermal tissues. second ring of meristematic tissue forms just below the epidermis in woody plants to produce bark. This is the cork cambium. The cork cambium and vascular cambium contribute to subsequent or secondary growth typically found only in woody plants. Now, roll over the apical meristem on the diagram..