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.
Leaves, stems, roots, and flowers are all made up of various tissues. Plant Tissues Plant Tissues fall into two large categories: Meristematic, or Permanent (Non-Meristematic) Meristematic Tissues Meristems are places in plants where cell division is occurring. During cell division, one cell becomes two cells.Each new cell can also divide.ateral meristems come in two basic types: Vascular cambium; meristematic tissue located between the xylem and phloem. The vascular cambium makes new xylem and phloem cells. Cork cambium; meristematic tissue located just below the bark in woody dicot stems. The cork cambium makes new bark cells.