Living World and Classification of Microbes

Vocabulary flashcards covering the hierarchy of biological classification, historical systems, Whittaker's five-kingdom system, and the characteristics of various microbes.

Biological classification

The process of dividing living organisms into groups and subgroups considering their similarities and differences.

Binomial Nomenclature Hierarchy

The levels of hierarchy considered while writing the name of organisms, specifically Genus and Species.

Carl Linnaeus (1735)

Scientist who divided the living world into two kingdoms: Vegetabilia and Animalia.

Haeckel (1866)

Scientist who considered three kingdoms: Protista, Plants, and Animals.

Chatton (1925)

Scientist who created two groups: Prokaryotes and Eukaryotes.

Kopland (1938)

Scientist who divided living organisms into four kingdoms: Monera, Protista, Plants, and Animals.

Robert Harding Whittaker

An American Ecologist (1920-1980) who in 1969 divided living organisms into five groups based on specific criteria.

Whittaker's Classification Criteria

Complexity of cell structure, complexity of organisms, mode of nutrition, life style, and phylogenetic relationship.

Kingdom Monera

Unicellular, prokaryotic organisms without a distinct nucleus or cell organelles; they may be autotrophic or heterotrophic.

Kingdom Protista

Single-celled organisms with a well-defined nucleus enclosed in a nuclear membrane, often using pseudopodia, cilia, or flagella for locomotion.

Kingdom Fungi

Non-green, eukaryotic, heterotrophic organisms that are mostly saprotrophs, with cell walls made of 'Chitin'.

Saprotrophs

Organisms that feed upon decaying organic matter.

Chitin

A tough and complex sugar that makes up the cell wall of fungi.

Bacteria

Unicellular, prokaryotic organisms ranging from $1\,\mu m$ to $10\,\mu m$ that reproduce by simple binary fission.

Protozoa

Unicellular eukaryotic organisms, approximately $200\,\mu m$ in size, found in soil, fresh water, and sea water.

Algae

Aquatic, eukaryotic, unicellular or multicellular autotrophic organisms sized $10\,\mu m$ to $100\,\mu m$.

Viruses

Independent particles of DNA or RNA covered by a protein coat, sized $10\,nm$ to $100\,nm$, considered at the edge of living and nonliving.

Binary fission

A simple method of reproduction where an organism gets divided equally into two identical daughter cells; bacteria can double their number this way in $20\,\text{minutes}$.

Micrometer ($\mu m$)

A unit of measurement where $1\,\text{meter} = 10^6\,\mu m$.

Nanometer ($nm$)

A unit of measurement where $1\,\text{meter} = 10^9\,nm$.

National Institute of Virology

An institute in Pune, founded in 1952 under the Indian Council of Medical Research, involved in research on viruses.