Page 46 - Pharmacognosy-II (06-PG 303)
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Herb
The term herb means (in Pharmacognosy) a drug composed of the tender parts of the plant axis (stem)
together with leaves, flowers, and fruits; according to the stem plants can be classified into: trees
(long, strong stem can grow for many years), shrubs (moderately tall and grow for few years) and
herbs (soft, non-woody stems that fall down at the end of the season “after fruiting’’.
Thus, the botanical description of herbs is a plant with non-woody stem which dies, at least down to
the ground, after fruiting. This term also includes lower plants ( Algae, Fungi, Lichens, etc…. ). Here,
we should establish the morphological and histological characteristics of the stem.
The Stem
The stem is that part of the plant axis which bears leaves at joints called nodes, these nodes are
connected by short or long segments called internodes.
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