Brief notes on two Types of Intercellular Spaces (Schizogenous & Lysigenous Spaces) !
Usually the meristematic or young cells do not possess any intercellular spaces among them but as they become older their walls split at certain places giving rise to small spaces called intercellular spaces, usually these are filled up with air or water. Generally there are two types of intercellular spaces—1. Schizogenous intercellular spaces and 2. Lysigenous intercellular spaces.
The most common intercellular spaces result from separation of cell walls from each other along more or less extended areas of their contact. In such cases, the intercellular substance dissolves partly and an intercellular space develops. Ultimately this becomes quite big in size and is known as schizogenous cavity.
The ordinary intercellular spaces and schizogenous cavities form an intercommunicating system of long intercellular canals which facilitate diffusion of gases and liquids from one part of the plant body to the other. The resin ducts in the Coniferales, and the secretory ducts in the Compositae and Umbelliferae are the typical examples. The cells lining the cavity are secretory in nature and release their product in the intercellular canal.
This type of intercellular space arises through dissolution of entire cells, which are therefore called lysigenous intercellular spaces (lysis, loosening, Greek). These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous plants. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples.