PlantTaxonomy

1. Natural Products and
Evidence based Herbal
medicines I
Department of Natural Products
and Alternative Medicine
Medicinal Botany
Part 3.
Plant TAXONOMY

2. Plant Taxonomy
and Subkingdom
and subclass

3. The following system of classification is used for the plant
kingdom:
The Plant Kingdom (PHYTA) is divided into three
subkingdoms:
PLANT TAXONOMY
A- Subkingdom PROTOPHYTA (primitive plants)
B- Subkingdom THALLOPHYTA (Non differentiated)
C- Subkingdom EMBRYOPHYTA (embryo present)

4. B- Subkingdom THALLOPHYTA
(body is a simple thallus, no embryo, not differentiated into stem, root& leaf
and dichotomous branching):
♣ Phylum Chlorophyta. e.g. green algae
♣ Phylum Bacillariophyta e.g. diatoms
♣ Phylum Phaeophyta (brown algae) e.g. Fucus
♣ Phylum Rhodophyta (red algae) e.g. Agar
♣ Phylum Eumycophyta (true fungi) e.g Ergot .
A- Subkingdom PROTOPHYTA
(primitive organisms)
♣Phylum Microtatobiotes (viruses, phages and rickettsiae)
♣ Phylum Schizomycophyta (bacteria)

5. C- Subkingdom EMBRYOPHYTA
(embryo present)
♣ Phylum BRYOPHYTA (Non-vascular).
♣ Phylum TRACHEOPHYTA (vascular plants).
Class Gymnosperm (conifers) e.g. Ginkgo
Class Angiosperm (flowering plants):
1. Subclass Dicotyledons (dicots).
2. Subclass Monocotyledons (monocots).
Phylum TRACHEOPHYTA (vascular plants):

6. Class Angiospermae (flowering plants):
The angiosperms (flowering plants) form the
highest class of Tracheophyta or vascular plants
and are divided into two subclasses:
A. Monocotyledoneae.
Their plants have following characters:
● The embryo has one cotyledon.
● The leaves are usually parallel –veined.
● The vascular bundles of the stem are closed.
A. Monocotyledoneae.
B. Dicotyledoneae.

7. Plants belonging to class angiospermae (flowering plants) of
medicinal importance families
Monocotyledoneae: Liliaceae and Zingiberaceae
Dicotyledoneae:Scruphulariaceae, Rubiaceae, Solanaceae
Papaveraceae, Compositae , Umbelliferae, Leguminosae and
Apocyanaceae.
B. Dicotyledoneae
Their plants have the following characters:
● The embryo has two cotyledons.
● The leaves are usually pinnately- veined.
● The vascular bundles are open.

8. Flowers are the organs of sexual reproduction of
higher plants and also generally offer the most exact
means of identification.
The structure of the flower :
A typical Flower is composed of the following floral parts :
1-Calyx (K): formed of green sepals (S), free or united .
2- Corolla (C): formed of colored petals (P), free or united
3-Androecium (A): formed of stamens, free or united
united with petals ( epipetalous ) .
4- Gynoecium (G) : formed of carpels ,each is made of
an ovary ,style ,and stigma .

10. Placentation:
It is the arrangement of ovules inside the ovary, of :
1-Axile in which the ovary is multilocular and the ovules
arise on the central placenta produced by the united edges
of the ovary walls .
2-Marginal ,Basal and Apical .

13. Symbols representing the floral parts:
Floral formula (FF):
FF represents its structure in a
symbolic way. The placentation is
usually referred to below the
symbol representing the
gynoecium.
Floral diagram (FD):
FD is another way of
representing the structure of the
flower.
It is an imaginary TS showing the
arrangement of parts. At the top
of FD, a point is usually drawn to
represent the axis of the flower.
At the base, the bract is present .
Calyx (sepals ) K (s)
Corolla (petals ) C (p)
Male flower ♂
Female flower ♀
Hermaphrodite ( bisexual ) ♀♂
Actinomorphic ( symmetric ) Ө
Zygomorphic (asymmetric ) %
Androecium A
Gynoecium G
Indefinite ∞
United parts ( )
Superior gynoecium G
Perigynous G
_
Inferior gynoecium G