This document discusses the taxonomic hierarchy used for classifying organisms, specifically angiosperms. It explains that taxonomic hierarchy arranges organisms into successive levels from kingdom down to species. The main levels are kingdom, division, class, order, family, genus, and species. Major categories include division, class, and order, while minor categories are genus and species. The hierarchy allows grouping of organisms based on their diversity and helps classify plants into appropriate groups.

1. M.Sc.II Sem - III
Paper X- Taxonomy of Angiosperms
Unit III
Dr. Swati Pundkar
Assistant Professor
Department of Botany
Shri Shivaji Science College, Amravati.

9. Taxonomic hierarchy
Taxonomic hierarchy is the
process of arranging various
organisms into successive
levels of the
biological classification either
in a decreasing or an
increasing order from kingdom
to species and vice versa.”
Each of this level of
the hierarchy is called
the taxonomic category or
rank .

12. Kingdom is the highest level or rank of the classification.
Example: Plantae
Division is the next level of classification that consists of
number of classes.
Example: Magnoliophyta.
Class consists of group of orders which share few
similarities.
Order includes group of families which show less
similarities among them.

13. Family comprises a number of genera which share
some similarities among them. Example: Asteraceae.
Genus consist of multiple species which have similar
characters but differ from the species of another genus.
Example: Helianthus, Tridax.
Species is the lowest of classification and shows the high
level of similarities among the organisms. For
example, Helianthus annuus and Helianthus tuberosus.
These two species differ in their morphology. Both of
them are herbs but Helianthus tuberosus is a perennial
herb.

14. Advantages of Taxonomic hierarchy
1)Grouping of living organisms into different categories
on the basis of degrees of diversity exhibited by them
is possible.
2)Such classification helps one to refer a particular group
of plants into appropriate classes.
There are two main categories
1)Major Categories-
Subdivision, Class, Order are together called Major
categories
2) Minor Categories-
Genus, Species, Variety are called Minor categories

15. Major categories
Division
Sub-division (ending with –eae)
Class (-opsida)
Sub-class (ideae)
Order (-ales/-ae)
Sub-order (-nieae)
Family (-aceae)(except 9 families)
Subfamily
Minor categories
Genus
Sub-genus (Section,Sub-section,Series,Sub-series)
Species

16. Infraspecific Categories-
Any category below the rank of spices is Infraspecific
category.
Most commonly used categories of this group are sub-
species, Variety and Forma.