CONCEPT FIVE KINGDOM CLASSIFICATION
The scientific procedure of arranging organisms into groups and subgroups on the basis of their similarities and dissimilarities and placing them in a
MAP
hierarchy of categories is called biological classification. The earliest classification systems recognised only two kingdoms of living things: Animalia and
Plantae followed by three and four kingdom classifications introducing Kingdom Monera and Protista. The most accepted and latest five-kingdom
classification was proposed by R.H. Whittaker in 1969 to develop phylogenetic relationships. In this classification, the organisms are classified on the basis
of following criteria : (i) complexity of cell, (ii) complexity of the body organisation, (iii) mode of nutrition, (iv) mode of reproduction, (v) ecological role and
(vi) phylogenetic relationships.
Classification Criteria
Major
Producer Decomposer Consumer
Ecological Role
Mode
Autotrophy (Photosynthesis) Heterotrophy (Absorption) Heterotrophy (Ingestion)
of Nutrition
KINGDOM FUNGI
KINGDOM ANIMALIA
l It contains achlorophyllous,
l It has maximum number and most
KINGDOM PLANTAE spore producing, multicellular or
diverse types of organisms.
multinucleate eukaryotic organisms.
l It contains all photosyn- l Organisms are multicellular eukaryotes. Body
l They have heterotrophic with absorptive
thetic eukaryotic multicellular form is regular. Cellular, tissue and organ system
type of nutrition i.e., either saprobic or parasitic.
plants and their non-photosynthetic levels of organisation occurs in different groups. A
l Cell wall contains chitin and noncellulosic
relatives. cell wall is absent. The organisms have holozoic or
polysaccharides. The cellular organisation is two
l Mode of nutrition is mainly autotrophic, ingestive type of nutrition. A few animals are,
envelope type.
hence called producers. Some of the plants are however, parasitic. They live on or inside the bodies
l Reproduction is both asexual and sexual.
heterotrophic, of which most are parasitic and a of other eukaryotes.
few are saprobes. Basidiomycota l Reproduction is mostly sexual.
l Cell wall is cellulosic. Food reserve is usually starch (Club fungi)
and fat. Chordata
l Reproduction is both asexual and sexual. (Chordates)
Angiospermae Echinodermata
Phaeophyta Ascomycota (Echinoderms)
Tracheophyta
(Brown algae) (Sac fungi) Mollusca
Deuteromycota (Molluscs)
(Fungi imperfecti)
Gymnospermae
Arthropoda
(Arthropods)
Zygomycota Annelida
Pteridophyta (Conjugation fungi) Nemathelminthes (Segmented worms)
(Roundworms)
Bryophyta Platyhelminthes
Oomycota Cnidaria
(Mosses and (Flatworms)
(Water molds) (Coelenterates)
liverworts) Porifera
(Sponges)
Rhodophyta
Chlorophyta (Red algae) Myxomycota
(Slime molds)
Multicellular (Green algae)
Euglenophyta KINGDOM PROTISTA
Unicellular
(Euglenoids) l It includes all unicellular and
colonial eukaryotes. Most of them are
Complexity aquatic organisms forming plankton. Sporozoa
l They have diverse modes of nutrition – (Sporozoans)
of Organism
DIRECTION OF EVOLUTION
photosynthetic, saprobic, parasitic, ingestive or holozoic,
etc. Genetic material is organised in the form of nucleus.
DNA is associated with histone. The aerobic forms possess
mitochondria and other membrane bound organelles.
Flagella, if present are 11-stranded with 9 + 2 organisation
of microtubules.
l These organisms with flexible lifestyles justifies the Ciliophora
erection of the intermediate eukaryotic Kingdom (Ciliates)
Chrysophyta
Protista. It is a connecting link between
Complexity (Diatoms and related algae)
prokaryotic Monera and the other Zoomastigina
of Cell Pyrrophyta
eukaryotic kingdoms. (Animal flagellates)
(Dinoflagellates)
Eukaryotes Primitive eukaryotic
flagellate
Prokaryotes
Cyanobacteria
(Blue green algae)
Eubacteria
(True bacteria) Archaebacteria
Viruses (Ancient bacteria)
Ÿ Viruses are intermediate between living and non-
living entities. These act as obligate parasites, i.e., KINGDOM MONERA
inert outside the host cell. l It includes basically unicelluar, microscopic
Ÿ They do not grow, divide or reproduce like typical living prokaryotes and the most primitive of living forms
organisms, rather reproduce using host machinery. with different modes of nutrition i.e., – saprobic, parasitic,
Ÿ Viruses are thus described as a nucleoprotein entity chemoautotrophic, photoautotrophic and symbiotic.
which is able to utilise the synthetic machinery of a l Cell wall comprises of peptidoglycan and polysaccharides other
living cell of another organism for its multiplication than cellulose. Cells have one envelope type of organisation but
and division. internal compartmentalisation is absent.
Ÿ They resemble living organisms in possessing genetic l If present, flagella are single stranded, genetic material
material and organic macromolecules and showing is not organised into a nucleus, DNA is naked i.e.,
mutations. without histone, all membrane bound cell
Ÿ They are responsible for a number of infectious organelles are absent. Sexual
diseases in plants, animals and humans. reproduction is absent as meiosis
does not occur.
