When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Biological organisation - Wikipedia

    en.wikipedia.org/wiki/Biological_organisation

    For example, genomes can be further subdivided into a hierarchy of genes. [4] Each level in the hierarchy can be described by its lower levels. For example, the organism may be described at any of its component levels, including the atomic, molecular, cellular, histological (tissue), organ and organ system levels.

  3. Tree of life (biology) - Wikipedia

    en.wikipedia.org/wiki/Tree_of_life_(biology)

    Edward Hitchcock's fold-out paleontological chart in his 1840 Elementary Geology. Although tree-like diagrams have long been used to organise knowledge, and although branching diagrams known as claves ("keys") were omnipresent in eighteenth-century natural history, it appears that the earliest tree diagram of natural order was the 1801 "Arbre botanique" (Botanical Tree) of the French ...

  4. Kingdom (biology) - Wikipedia

    en.wikipedia.org/wiki/Kingdom_(biology)

    The hierarchy of biological classification's eight major taxonomic ranks.A domain contains one or more kingdoms. Intermediate minor rankings are not shown. In biology, a kingdom is the second highest taxonomic rank, just below domain.

  5. Biological system - Wikipedia

    en.wikipedia.org/wiki/Biological_system

    Biological organization spans several scales and are determined based different structures depending on what the system is. [1] Examples of biological systems at the macro scale are populations of organisms. On the organ and tissue scale in mammals and other animals, examples include the circulatory system, the respiratory system, and the ...

  6. Taxonomic rank - Wikipedia

    en.wikipedia.org/wiki/Taxonomic_rank

    In biology, taxonomic rank (which some authors prefer to call nomenclatural rank [1] because ranking is part of nomenclature rather than taxonomy proper, according to some definitions of these terms) is the relative or absolute level of a group of organisms (a taxon) in a hierarchy that reflects evolutionary relationships.

  7. Clade - Wikipedia

    en.wikipedia.org/wiki/Clade

    In the diagram, lemurs and lorises are sister clades, while humans and tarsiers are not. A clade A is basal to a clade B if A branches off the lineage leading to B before the first branch leading only to members of B. In the adjacent diagram, the strepsirrhine/prosimian clade, is basal to the hominoids/ape clade. In this example, both ...

  8. Phylogenetic tree - Wikipedia

    en.wikipedia.org/wiki/Phylogenetic_tree

    The idea of a tree of life arose from ancient notions of a ladder-like progression from lower into higher forms of life (such as in the Great Chain of Being).Early representations of "branching" phylogenetic trees include a "paleontological chart" showing the geological relationships among plants and animals in the book Elementary Geology, by Edward Hitchcock (first edition: 1840).

  9. Living systems - Wikipedia

    en.wikipedia.org/wiki/Living_systems

    A closely related approach, relational biology, is concerned mainly with understanding life processes in terms of the most important relations, and categories of such relations among the essential functional components of organisms; for multicellular organisms, this has been defined as "categorical biology", or a model representation of ...