Binomial Nomenclature and Kingdom Systems

1.0Kingdom Systems

What is Kingdom System Classification?

Two Kingdom Classification

First suggested by Carolus Linnaeus in 1758. Living organisms were divided into two kingdoms by him.

Kingdom Plantae: All the plants constitute kingdom plantae. The kingdom includes bacteria, lichens, fungi, algae, bryophytes, ferns, gymnosperms and angiosperms.

Kingdom Animalia: All the animals constitute kingdom animalia. The animal kingdom animalia includes protozoans, sponges, Hydra, jellyfish, worms, insects, spiders, octopus, star fish, fishes, frogs, salamanders, lizards, snakes, birds and mammals.

Drawbacks of Two Kingdom Classification

Certain organisms did not strictly fit either under plant or animal kingdom like: Euglena and viruses.

Three Kingdom Classification

Three kingdom classification was proposed by Ernst Haeckel in 1886.

He suggested a third Kingdom Protista for unicellular organisms.

Four Kingdom Classification

Four kingdom classification was given by Copeland. He included Kingdom Monera (Mychota) for prokaryotes.

Five Kingdom Classification

This concept was propounded by Robert H. Whittaker in 1969.

On the basis of cell structure, complexity in organisms and type of nutrition, he divided living organisms into 5 kingdoms.

(i) Monera (ii) Protista (iii) Fungi (iv) Plantae (v) Animalia

Carl Woese (1977-1994) has divided the kingdom Monera into Archaebacteria (archaea) and Eubacteria (bacteria). All other kingdoms are included in eukaryotes.

Carolus Linnaeus (Karl Von Linne) published 14 papers and also brought out the famous book ‘Systema Naturae’ from which all fundamental taxonomical researches have taken off.

Characteristic of Five Kingdoms

Kingdom - Monera: All the prokaryotic unicellular organisms are included in Monera.

Prokaryotic Nature: The genetic material is not organised into a nucleus. It lies directly inside the cytoplasm and is called a nucleoid. Membrane bound cell organelles like mitochondria, Golgi apparatus, plastids, lysosomes are absent.

Unicellular Nature: Monerans are basically unicellular. In filaments and colonies, the cells are similar and independent.

Mode of nutrition is either autotrophic (Blue-green algae) or heterotrophic (Mycoplasma and most bacteria).

Some organisms have cell walls (in bacteria and blue-green algae) while others are lacking (in Mycoplasma).

• Blue green algae perform nitrogen fixation due to the presence of heterocyst. The cell wall of bacteria is made up of peptidoglycan (Murine).
• All nitrogen fixing organisms belong to Monera (e.g., Rhizobium in root nodules of legumes). Some monerans take part in ammonification, nitrification and denitrification.

e.g. Blue Green Algae (Cyanobacteria) - Anabaena, Nostoc.

Bacteria - Vibrio cholerae, Clostridium botulinum, Escherichia coli

Mycoplasma - Produces diseases in humans, animals and plants.

Kingdom - Protista

Organisms are unicellular which have eukaryotic organization.

There is a true nucleus and membrane bound to other cell organelles.

Some protists are covered with cell walls (most photosynthetic protists) while others do not possess it (e.g., protozoan protists).

Mode of nutrition is either autotrophic (algae and diatoms) or heterotrophic (protozoans). Some organisms have hair like cilia (e.g. Paramecium); whip-like flagellum (e.g. Euglena) and pseudopodia (e.g. Amoeba) for locomotion.

e.g. Unicellular algae – Chlamydomonas, Chlorella

Diatoms,  Dinoflagellates

Protozoa – Amoeba, Plasmodium, Euglena, Paramecium.

• Euglena and its relatives perform photosynthesis in light. In the dark and in the presence of organic matter, they switch over to saprophytic nutrition. Such a dual nutrition is called mixotrophic nutrition. Organisms with mixotrophic nutrition are called plant-animals.

Kingdom - Fungi

These are non-green (lacking chlorophyll) eukaryotic organisms. They may be unicellular (e.g. Yeast) or Multicellular (most fungi). Heterotrophic mode of nutrition is found. Food is gained either saprophytically (from dead organic matter) or parasitically (from other living tissues). The cell wall is made up of Chitin. Reserve food material is Glycogen.

• The body of a multicellular and filamentous fungus is called mycelium. It is composed of several thread-like structures termed hyphae.

e.g. Yeast, Rhizopus (Bread mould), Penicillium, Mucor, Mushroom (Agaricus), Smut (Ustilago).

Lichen: Symbiotic association between algae (mostly blue green algae or cyanobacteria) and fungi is known as lichen. The alga manufactures food not only for itself but also for the fungus. Fungus provides protection to alga, helps in fixation and absorption of water as well as minerals. Lichens can be seen as the slow growing large coloured patches on the bark of trees. They are a source of essences, dhup, havan samagri and some medicines.

Lichens are used as bio- indicators for air pollution as they are sensitive towards SO₂ pollution.

e.g. Rhizocarpon, Parmelia and Usnea

Kingdom - Plantae

Plants are multicellular, eukaryotes with cellulosic cell wall.

They are autotrophs i.e. prepare own food by photosynthesis by using chlorophyll.

Kingdom - Animalia

Animals are multicellular, eukaryotes without cell walls.

They are heterotrophic.

2.0Binomial Nomenclature

Binomial nomenclature was proposed by Carolus Linnaeus. According to him the name of any organism consists of two words.

The first word denotes the name of ‘genus’ and the second word denotes ‘species’.

Certain conventions are followed while writing the scientific names:

(1) The first letter of a generic name must be written in capital letters whereas a species name is started with a small letter.

(2) Scientific names are generally derived from Greek or Latin words.

(3) The binomial names are printed in italics and underlined separately when written. e.g. Potato - Solanum tuberosum, Tiger - Panthera Tigris.

3.0Also Read