Page 8 - pharmacognosy2- pharmD- e-book
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Medicinal Herbs
The term herb means (in Pharmacognosy) a drug composed of the tender parts of the plant axis
(stem) together with leaves, flowers, and fruits; or (in Botany) 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.
Classification of the Plant kingdom
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