instance_of splitstree
In ___MASK10___ , a square ___MASK12___ is a ___MASK12___ with the same number of rows and columns . An " n "- by -" n " ___MASK12___ is known as a square ___MASK12___ of ___MASK15___ " n ". Any two square matrices of the same ___MASK15___ can be added and multiplied . Evolution is ___MASK52___ in the heritable characteristics of biological populations over successive generations . Evolutionary processes give rise to biodiversity at every level of biological organisation , including the levels of ___MASK17___ , individual organisms , and molecules . In neuropsychology , linguistics and the ___MASK45___ of ___MASK96___ , a ___MASK37___ or ordinary ___MASK96___ is any ___MASK96___ that has evolved naturally in humans through use and repetition without conscious planning or premeditation . Natural languages can take different forms , such as speech , signing , or writing . They are distinguished from constructed and formal languages such as those used to program computers or to study logic . A phylogenetic network or reticulation is any ___MASK82___ used to visualize evolutionary relationships ( either abstractly or explicitly ) between nucleotide sequences , genes , chromosomes , genomes , or species . They are employed when reticulation events such as hybridization , horizontal gene transfer , recombination , or gene duplication and loss are believed to be involved . They differ from phylogenetic trees by the explicit modeling of richly - linked networks , by means of the addition of hybrid nodes ( nodes with two parents ) instead of only tree nodes ( a hierarchy of nodes , each with only one parent ). Phylogenetic trees are a subset of phylogenetic networks . Phylogenetic networks can be inferred and visualised with ___MASK1___ such as SplitsTree and , more recently , Dendroscope . A standard format for representing phylogenetic networks is a variant of Newick format which is extended to support networks as well as trees . In ___MASK10___ , computer science and especially ___MASK4___ , a ___MASK44___ ___MASK12___ is a square ___MASK12___ ( two - dimensional array ) containing the distances , taken pairwise , between the elements of a set . Depending upon the ___MASK49___ involved , the " ___MASK44___ " being used to define this ___MASK12___ may or may not be a metric . If there are elements , this ___MASK12___ will have size . In graph - theoretic applications the elements are more often referred to as points , nodes or vertices . Nucleotides are organic molecules that serve as the monomers , or subunits , of nucleic acids like ___MASK72___ ( deoxyribonucleic ___MASK58___ ) and RNA ( ribonucleic ___MASK58___ ). The ___MASK78___ blocks of nucleic acids , nucleotides are composed of a nitrogenous ___MASK55___ , a five - carbon sugar ( ribose or deoxyribose ), and at least one phosphate group . A nucleoside is a nitrogenuous ___MASK55___ and a 5 - carbon sugar . Thus a nucleoside plus a phosphate group yields a nucleotide . Nucleotides are also known as phosphate nucleotides . Deoxyribonucleic ___MASK58___ ( DNA ) is a ___MASK47___ that carries the genetic instructions used in the growth , development , functioning and reproduction of all known living organisms and many viruses . DNA and RNA are nucleic acids ; alongside proteins , lipids and complex carbohydrates ( polysaccharides ), they are one of the four major types of macromolecules that are essential for all known forms of life . Most DNA molecules consist of two biopolymer strands coiled around each other to form a double helix . In ___MASK10___ ___MASK4___ is the ___MASK2___ of " graphs ", which are mathematical structures used to model pairwise relations between objects . A graph in this context is made up of " vertices ", " nodes ", or " points " which are connected by " edges ", " arcs ", or " lines ". A graph ___MASK87___ be " undirected ", meaning that there is no distinction between the two vertices associated with each edge , or its edges ___MASK87___ be " directed " from one vertex to another ; see Graph ( discrete ___MASK10___ ) for more detailed definitions and for other variations in the types of graph that are commonly considered . Graphs are one of the prime objects of ___MASK2___ in discrete ___MASK10___ . In bioinformatics , a ___MASK6___ alignment is a way of arranging the sequences of ___MASK72___ , RNA , or protein to identify regions of similarity that may be a consequence of functional , structural , or evolutionary relationships between the sequences . Aligned sequences of nucleotide or amino ___MASK58___ residues are typically represented as rows within a ___MASK12___ . Gaps are inserted between the residues so that identical or similar characters are aligned in successive columns . Sequence alignments are also used for non - biological sequences , such as calculating the edit distance cost between strings in a ___MASK37___ or in financial data . ___MASK18___ ___MASK84___ is the study of the ___MASK93___ , experimentation , and engineering that form the basis for the ___MASK11___ and use of computers . It is the scientific and practical approach to computation and its applications and the systematic study of the feasibility , ___MASK92___ , expression , and mechanization of the methodical procedures ( or algorithms ) that underlie the acquisition , representation , processing , storage , communication of , and access to information . An alternate , more succinct definition of computer ___MASK84___ is the study of automating algorithmic processes that scale . A computer scientist specializes in the ___MASK93___ of computation and the ___MASK11___ of computational systems . Ribonucleic ___MASK58___ ( RNA ) is a polymeric ___MASK47___ essential in various biological roles in coding , decoding , regulation , and expression of genes . RNA and DNA are nucleic acids , and , along with proteins and carbohydrates , constitute the four major macromolecules essential for all known forms of life . Like DNA , RNA is assembled as a chain of nucleotides , but unlike DNA it is more often found in nature as a single - strand folded onto itself , rather than a paired double - strand . Cellular organisms use messenger RNA ( mRNA ) to convey genetic information ( using the letters G , U , A , and C to denote the nitrogenous bases guanine , uracil , adenine , and cytosine ) that directs synthesis of specific proteins . Many viruses encode their genetic information using an RNA genome . ___MASK10___ ( from Greek  " máthma ",  knowledge , study , learning ) is the study of topics such as quantity ( numbers ), ___MASK92___ , space , and change . There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics . Proteins ( or ) are large biomolecules , or macromolecules , consisting of one or more long chains of amino ___MASK58___ residues . Proteins perform a vast array of functions within organisms , including catalysing metabolic reactions , DNA replication , responding to stimuli , and transporting molecules from one ___MASK74___ to another . Proteins differ from one another primarily in their sequence of amino acids , which is dictated by the nucleotide sequence of their genes , and which usually results in protein folding into a specific three - dimensional ___MASK92___ that determines its activity . Amino acids are biologically important organic compounds containing ___MASK13___ (- NH ) and carboxyl (- COOH ) functional groups , along with a side - ___MASK20___ ( R group ) specific to each amino acid . The key elements of an amino acid are carbon , hydrogen , oxygen , and nitrogen , though other elements are found in the side - chains of certain amino acids . About 500 amino acids are known ( though only 20 appear in the genetic code ) and can be classified in many ways . They can be classified according to the core structural functional groups ' locations as alpha - (  -), beta - (  -), gamma - (  -) or delta - (  -) amino acids ; other categories relate to polarity , pH level , and side - ___MASK20___ group type ( aliphatic , acyclic , aromatic , containing hydroxyl or sulfur , etc .). In the form of proteins , amino acids comprise the second - largest component ( ___MASK38___ is the largest ) of human muscles , cells and other tissues . Outside proteins , amino acids perform critical roles in processes such as neurotransmitter transport and biosynthesis . Bioinformatics is an interdisciplinary ___MASK28___ that develops methods and ___MASK1___ tools for understanding biological data . As an interdisciplinary ___MASK28___ of science , bioinformatics combines computer science , statistics , mathematics , and engineering to analyze and interpret biological data . Bioinformatics has been used for " in silico " analyses of biological queries using mathematical and statistical techniques . SplitsTree is a popular program for inferring phylogenetic trees or , more generally , phylogenetic networks from various types of ___MASK70___ such as a sequence alignment , a distance ___MASK12___ or a set of trees . SplitsTree implements published methods such as split decomposition neighbor - net , consensus networks , super networks methods or methods for computing hybridization or simple recombination networks .