Biology/Citable Version

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The word "Biology" is formed by combining the Greek βίος (bios), meaning 'life', and λόγος (logos), meaning 'study of'. "Biology" in its modern use was probably introduced independently by both Gottfried Reinhold Treviranus (Biologie oder Philosophie der lebenden Natur, 1802) and by Jean-Baptiste Lamarck (Hydrogéologie, 1802). Although the word "biology" is sometimes said to have been coined in 1800 by Karl Friedrich Burdach, it appears in the title of Volume 3 of Michael Christoph Hanov's Philosophiae naturalis sive physicae dogmaticae: Geologia, biologia, phytologia generalis et dendrologia, published in 1766.</ref>

(revision Note:" The word biology" narrative may have its own section later in the article, may be put in a standard place for word roots, but cannot be included in the introduction of the article without ringing down the curtain for the audience.)


Biology is the science of life. Biologists study every aspect of living things, including all of the many life forms on earth, and each of the processes within them that enable life. Those basic processes include the harnessing of energy, the creation of the many different materials that make up their bodies, and the assembly of these components to build organs and structures, to correct errors and repair injuries, to sense their environment and to make sense of it, to reproduce themselves, and to communicate with others. Cite error: Closing </ref> missing for <ref> tag Further developments led to the modern compound microscope by the end of the 19th century, with much higher resolution, and eventually the late 20th century electron microscopes (Image needed?).

Like all important technological advances in biology, the microsocope led to new ideas about living things. The concept that tissues were composed of cells was clarified, thefield of microbiology was born, and the ground was prepared for the germ theory of disease, an idea that helped bring the traditional practice of western medicine (sometimes called allopathy) into the field of health science and modern medicine.

Classification

Classification is the province of the disciplines of systematics and taxonomy. Taxonomy places organisms in groups called taxa, while systematics seeks to define their relationships with each other. This classification technique has evolved to reflect advances in cladistics and genetics, shifting the focus from physical similarities and shared characteristics to phylogenetics.

The dominant classification system is called Linnaean taxonomy, which includes ranks and binomial nomenclature. How organisms are named is governed by international agreements such as the International Code of Botanical Nomenclature (ICBN), the International Code of Zoological Nomenclature (ICZN), and the International Code of Nomenclature of Bacteria (ICNB). The PhyloCode is a formal set of rules governing phylogenetic nomenclature that is being established as an attempt to standardize naming in these three areas[1]. The Virus cInternational Code of Virus Classification and Nomenclature (ICVCN) remains outside the PhyloCode.

Traditionally, living things have been divided into five kingdoms:

Monera -- Protista -- Fungi -- Plantae -- Animalia

However, many scientists now consider this five-kingdom system to be outdated. Modern alternative classification systems generally begin with the three-domain system[2]:

Archaea (originally Archaebacteria) -- Bacteria (originally Eubacteria) -- Eukaryota

These domains reflect whether the cells have nuclei or not, as well as differences in the cell exteriors.

Further, each kingdom is broken down continuously until each species is separately classified. The order is 1) Kingdom, 2) Phylum, 3) Class, 4) Order, 5) Family, 6) Genus, 7) Species. The scientific name of an organism is obtained from its Genus and Species. For example, humans would be listed as Homo sapiens. Homo would be the Genus and Sapiens is the species. Whenever writing the scientific name of an organism it is proper to capitalize the first letter in the genus and put all of the species in lowercase; in addition the entire term would be put in italics. The term used for classification is called Taxonomy.

There is also a series of intracellular parasites that are progressively "less alive" in terms of metabolic activity:

Viruses -- Viroids -- Prions


Main topics and discoveries

For more information, see: List of biology topics.

Major discoveries in biology include:

Disciplines within biology

For more information, see: List of biology disciplines.


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References

Citations
  1. Phylocode outlines nomenclature that is designed to name the parts of the tree of life by explicit reference to phylogeny.
  2. Tree of Life Web Project (ToL) is a collaborative effort of biologists from around the world.
Further reading

Selected external links

The following links have been reviewed and are recommended because, at the time of their inclusion, they provided accurate information and portals to additional excellent web resources. Many other excellent links have been omitted through no fault of their own.

Plain and technical language