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  2. Characteristic class - Wikipedia

    en.wikipedia.org/wiki/Characteristic_class

    Characteristic classes are elements of cohomology groups; [1] one can obtain integers from characteristic classes, called characteristic numbers. Some important examples of characteristic numbers are Stiefel–Whitney numbers , Chern numbers , Pontryagin numbers , and the Euler characteristic .

  3. Linnaean taxonomy - Wikipedia

    en.wikipedia.org/wiki/Linnaean_taxonomy

    Linnaean taxonomy can mean either of two related concepts: The particular form of biological classification (taxonomy) set up by Carl Linnaeus, as set forth in his Systema Naturae (1735) and subsequent works. In the taxonomy of Linnaeus there are three kingdoms, divided into classes, and the classes divided into lower ranks in a hierarchical order.

  4. Taxonomic rank - Wikipedia

    en.wikipedia.org/wiki/Taxonomic_rank

    Cladistics is a method of classification of life forms according to the proportion of characteristics that they have in common (called synapomorphies). It is assumed that the higher the proportion of characteristics that two organisms share, the more recently they both came from a common ancestor.

  5. Cladogram - Wikipedia

    en.wikipedia.org/wiki/Cladogram

    The characteristics used to create a cladogram can be roughly categorized as either morphological (synapsid skull, warm blooded, notochord, unicellular, etc.) or molecular (DNA, RNA, or other genetic information). [7] Prior to the advent of DNA sequencing, cladistic analysis primarily used morphological data.

  6. Taxonomy (biology) - Wikipedia

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

    Turrill (1935) has suggested that while accepting the older invaluable taxonomy, based on structure, and conveniently designated "alpha", it is possible to glimpse a far-distant taxonomy built upon as wide a basis of morphological and physiological facts as possible, and one in which "place is found for all observational and experimental data ...

  7. Rossmann fold - Wikipedia

    en.wikipedia.org/wiki/Rossmann_fold

    The Rossmann fold is a tertiary fold found in proteins that bind nucleotides, such as enzyme cofactors FAD, NAD +, and NADP +.This fold is composed of alternating beta strands and alpha helical segments where the beta strands are hydrogen bonded to each other forming an extended beta sheet and the alpha helices surround both faces of the sheet to produce a three-layered sandwich.

  8. Phylogenetics - Wikipedia

    en.wikipedia.org/wiki/Phylogenetics

    Phylogenetics is a component of systematics that uses similarities and differences of the characteristics of species to interpret their evolutionary relationships and origins. Phylogenetics focuses on whether the characteristics of a species reinforce a phylogenetic inference that it diverged from the most recent common ancestor of a taxonomic ...

  9. Forensic footwear evidence - Wikipedia

    en.wikipedia.org/wiki/Forensic_footwear_evidence

    If class characteristics, size match and randomly acquired characteristics found in the footwear outsole can also be found in the crime scene impressions: Investigators can determine that the specific piece created the crime scene impression. This relationship can be used as evidence to prove that the footwear's owner was at the crime scene.