ABSTRACT
The central region of a plant cell commonly contains a large vacuole that maintains cellular rigidity through the pressure of water within, as well as serving to traffic and store various molecules, although stem cells in plants differ by having small vacuoles. The range of distinct differentiated cell types and their organization into functional structures varies between the three categories of plants and has a bearing on their requirements for specialized cells, analogous to stem cells in animals, which have the potential to maintain growth throughout a plant's lifetime. The stem cells in a meristem are small and lack many of the features that characterize differentiated plant cells, including having only a very thin cell wall and extremely small vacuoles and lacking fully formed plastids in their cytoplasm. Comparison of stem cells between the two apical meristems shows that unlike shoot apical meristem stem cells that are able to give rise to all aerial tissues.
