Meristems or meristematic tissues are the tissues which are made up of group of immature and similar cells, that are in continuous state of division, forming new cells. The cells of a meristematic tissue are characterised by the following features :
(a) The cells are immature and are capable of dividing indefinitely.
(b) They are small and thin walled cells, without intercellular spaces.
(c) The cells are generally isodiametric (almost of same length and breath) and are rounded, oval or polygonal in outline.
(d) They have thin and elastic cell wall, made up of cellulose.
(e) The vacuoles are absent or are very small. Cambium cells, however, possess large vacuoles.
(f) The plastids are present in proplastid stage.
(g) The cells do not store reserve food and are in active stage of metabolism.
(h) The cells lack inorganic crystals and other ergastic substances.
(i) The meristematic cells are mother cells from which all other types of cells are formed.