Homology sentence example
Although the name of continent was not applied to large portions of land for any physical reasons, it so happens that there is a certain physical similarity or homology between them which is not shared by the smaller islands or peninsulas.
Furthermore, the theory of homology decompositions was developed in a much more general context which will allow further generalizations.
It is open to question, however, how far the evidence from such " heteromorphic regeneration " can be regarded as conclusive on the points of homology.
This kinase domain shows approximately 84% homology with the insulin receptor.
The genes for hK2 and PSA are expressed predominately in the prostate, are transcriptionally up-regulated by androgens, and share 78% homology.Advertisement
A human T cell-specific cDNA clone encodes a protein having extensive homology to immunoglobulin chains.
Projector thus uses sequence homology directly at DNA level and takes the conservation of gene structures between related genes explicitly into account.
Neither primer had significant sequence homology with any other DNA component of BBTV.
The full-length sequence exhibits little overall homology to any other known protein at either the nucleotide or the amino acid level.
This is especially the case after building by homology from a structure with a high homology, or after making a few point mutants.Advertisement
Its amino acid sequence shows much greater homology to consensus sequences derived from protein serine/threonine kinases than to the consensus for protein tyrosine kinases.
Many signal proteins bind via lipid anchors and/or pleckstrin homology domains to the cytosolic surface of the plasma membrane.
The database is searchable by sequence name, sequence homology or direct SQL query.
Block Searcher, Get Blocks and Block Maker are aids to detection and verification of protein sequence homology.
Clues to the normal function of MLL in mammalian haematopoiesis have come from the identification of domains that share homology with other known proteins.Advertisement
Unfortunately the homology of the functional series does not by any means end the uncertainty connected with the marsupial dentition; as there is also a difference of opinion with regard to the serial homology of some of the cheek-teeth.
Alternatively a gene can be selected by chromosomal location or by sequence homology using a customized BLAST search.
It must be pointed out that, however probable Haeckel's theory may be in other respects, there is not the slightest evidence for any such cleft in the umbrella having been present at any time, and that the embryological evidence, as already pointed out, is all against any homology between the stem and a manubrium, since the primary siphon does not become the stem, which arises from the ex-umbral side of the protocodon and is strictly comparable to a stolon.
The homology of members was based, in the first instance, upon similarity of development and upon similar relations to the other parts of the body, that is, upon ontogeny.
But since the general adoption of the theory of evolution, similarity of descent, that is of p/iylogeny, has come to form an essential part of this conception; in other words, in order that their homology may be established the parts compared must be proved to be homogenetic.Advertisement
The effect of the phylogenetic factor in homology may be illustrated in the following cases.
Another effect is that different degrees of homology have to be recognized, just as there are different degrees of relationship or affinity between individual plants.
The relief of the surface typically includes a central plain, Homology sometimes dipping below sea-level, bounded by lateral Homology of con- h i ghlands or mountain ranges, loftier on one side than.
The compound eyes of insects resemble so closely the similar organs in Crustaceans that there can hardly be reasonable doubt of their homology, and the primitively appendicular nature of the eyes in the latter class suggests that in the Hexapoda also they represent the appendages of an anterior (protocerebral) segment.
Owen not only occupied himself with the dissection of rare animals, such as the Pearly Nautilus, Lingula, Limulus, Protopterus, Apteryx, &c., and with the description and reconstruction of extinct reptiles, birds and mammals - following the Cuvierian tradition - but gave precision and currency to the morphological doctrines which had taken their rise in the beginning of the century by the introduction of two terms, " homology " and " analogy," which were defined so as to express two different kinds of agreement in animal structures, which, owing to the want of such " counters of thought," had been hitherto continually confused.Advertisement
It is the old distinction between homology and analogy on a grand scale.
Homogeny, in contrast, the " special homology " of Owen, is the supreme test of kinship or of hereditary relationship, and thus the basis of all sound reasoning in phylogeny.
This mode of sporeformation is totally different from that in the ascus; hence one of the difficulties of the acceptance of Brefeld's view of the homology of ascus and sporangium.
In the various groups of the Entomostraca, on the other hand, the terms thorax and abdomen, though conveniently employed for purposes of systematic description, do not imply any homology with the regions so named in the Malacostraca.
The structure of the zooid of Heliopora, however, is that of a typical Alcyonarian, and the septa have only a resemblance to, but no real homology with, the similarly named structures in madreporarian corals.
For, whereas to one brilliant suggestion of far-reaching homology another can always be opposed, by the detailed comparison of individual growth-stages in carefully selected series of fossils, and by the minute application to these of the principle that individual history repeats race history, it actually is possible to unfold lines of descent that do not admit of doubt.
Accepting the homology of these apical systems with the calycinal system, the theory would regard the aboral pole of a sea-urchin or starfish as corresponding in everything, except its relations to the sea-floor, with the aboral pole of a fixed echinoderm.
S, Blood-spaces, of which the homology is still uncertain.
Similar binding sites in terms of surface shape and properties, but which have low homology with the reference structure, may also exist.
But it is obvious to every one who nowadays indulges in the profitless pastime of studying their writings that, as a whole, they failed in grasping the essential difference between homology (or " affinity," as they generally termed it) and analogy - though this difference had been fully understood and set forth by Aristotle himself - and, moreover, that in seeking for analogies on which to base their foregone conclusions they were often put to hard shifts.
When two organs can be traced along the same line of descent to one primitive form, that is when they are found to be mono phyletic, their homology is complete; when, however, they are traceable to two primitive forms, though these forms belong to the same morphological series, they are polyphyletic and therefore only incompletely homologous.
Thus the histological differentiation of the sporogonium of the higher mosses is one of considerable complexity; but there is here even less reason to suppose that these tissues have any homology (phylogenetic community of origin) with the similar ones met with in the higher plants.