What's the difference between homology and parallelism?

Homology


Definition:

  • (n.) The quality of being homologous; correspondence; relation; as, the homologyof similar polygons.
  • (n.) Correspondence or relation in type of structure in contradistinction to similarity of function; as, the relation in structure between the leg and arm of a man; or that between the arm of a man, the fore leg of a horse, the wing of a bird, and the fin of a fish, all these organs being modifications of one type of structure.
  • (n.) The correspondence or resemblance of substances belonging to the same type or series; a similarity of composition varying by a small, regular difference, and usually attended by a regular variation in physical properties; as, there is an homology between methane, CH4, ethane, C2H6, propane, C3H8, etc., all members of the paraffin series. In an extended sense, the term is applied to the relation between chemical elements of the same group; as, chlorine, bromine, and iodine are said to be in homology with each other. Cf. Heterology.

Example Sentences:

  • (1) Trifluoroacetylated rabbit serum albumin was 5 times more reactive with these antibodies and thus more antigenic than the homologous acetylated moiety confirming the importance of the trifluoromethyl moiety as an epitope in the immunogen in vivo.
  • (2) The ORF2 showed homology with the Escherichia coli regulatory gene ompR, and ORF4 showed homology with E. coli and Rhizobium meliloti regulatory genes fnr and fixK, respectively.
  • (3) Nucleotide sequence analysis of cDNAs for asparagine synthetase (AS) of Pisum sativum has uncovered two distinct AS mRNAs (AS1 and AS2) encoding polypeptides that are highly homologous to the human AS enzyme.
  • (4) In four main regions the conservation varied from 83-91% while in the remaining regions the homology dropped to between 56-62%.
  • (5) It has 61% homology with tRNA(Leu)(anticodon m5CAA) and 63% homology with tRNA(Leu)(anticodon UAG), the two other known yeast tRNAs(Leu).
  • (6) The specified region of the inner E2 core domain was highly homologous to the region of the E2 subunit of pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase.
  • (7) This novel mechanism of receptor regulation, named transmodulation, should be distinguished from the reduction in total receptor number caused by the homologous ligand (downregulation) and from the change in affinity produced by the binding of agonists or antagonists to the same receptor site.
  • (8) This unusual insertion could affect the interaction of cat CD4 with class II molecules, or with FIV, a feline homolog of HIV.
  • (9) On the basis of primary sequence homology with other known Pseudomonas lipases, a number of putative active site residues located in conserved areas were found.
  • (10) Extensive sequence homologies and other genetic features are shared with the related oncogenic virus, human papillomavirus type 16, especially in the major reading frames.
  • (11) Since the plasmid-cured strains did not contain DNA sequences homologous to plasmid DNA, the gene for the free-inclusion protein must be encoded in the chromosome.
  • (12) Examination of the deduced amino acid sequence revealed an apparent homology to cAMP binding sites in several other proteins.
  • (13) Thus, introduction of arginine in position 5 with a hydrophobic amino acid in position 6 is compatible with high potency in several biological systems and results in compounds with lowered potency to release histamine compared to homologous peptides with tyrosine in position 5 and D-arginine in position 6.
  • (14) This receptor and a growing family of related cytokine receptors share homologous extracellular features, including a well-conserved WSXWS motif.
  • (15) Amino acid analysis indicated a significant number of serine amino acids: N-terminal sequence data demonstrated a high level of homology; and trypsin digestion followed by reversed-phase HPLC indicated the possibility of multiple phosphorylation sites.
  • (16) Homologous insemination in 52 couples during a period of one year yields a conception rate of 38.5%.
  • (17) The region is distinctive in that the sequence is absent from the homologous domain of the erythroid alpha chain and diverges from the normal internal repeat structure observed throughout other spectrins.
  • (18) Surrounding intact ipsilateral structures are more important for the recovery of some of the language functions, such as motor output and phonemic assembly, than homologous contralateral structures.
  • (19) The results show that in both viral DNAs cleavage occurs at the origin and at one additional site which shows striking sequence homology with the origin region.
  • (20) The most striking homology was to yeast SEC7 in the central domain of the gene (57% identical over 466 bp) and also the protein level (42% identical amino acids; 39% conserved amino acids).

Parallelism


Definition:

  • (n.) The quality or state of being parallel.
  • (n.) Resemblance; correspondence; similarity.
  • (n.) Similarity of construction or meaning of clauses placed side by side, especially clauses expressing the same sentiment with slight modifications, as is common in Hebrew poetry; e. g.: --//At her feet he bowed, he fell:/Where he bowed, there he fell down dead. Judg. v. 27.

Example Sentences:

  • (1) When the data correlating DHT with protein synthesis using both labelling techniques were combined, the curves were parallel and a strong correlation was noted between DHT and protein synthesis over a wide range of values (P less than 0.001).
  • (2) The time-course and dose-response for this modification of pp60c-src paralleled PDGF-induced increases in phosphorylation of pp36, a major cellular substrate for several tyrosine-specific protein kinases.
  • (3) We present a mathematical model that is suitable to reconcile this apparent contradiction in the interpretation of the epidemiological data: the observed parallel time series for the spread of AIDS in groups with different risk of infection can be realized by computer simulation, if one assumes that the outbreak of full-blown AIDS only occurs if HIV and a certain infectious coagent (cofactor) CO are present.
  • (4) There was no correlation between serum LH and chronological or bone age in this age group, which suggests that the correlation found is not due to age-related parallel phenomena.
  • (5) The cyclical nature of pyromania has parallels in cycles of reform in standards of civil commitment (Livermore, Malmquist & Meehl, 1958; Dershowitz, 1974), in the use of physical therapies and medications (Tourney, 1967; Mora, 1974), in treatment of the chronically mentally ill (Deutsch, 1949; Morrissey & Goldman, 1984), and in institutional practices (Treffert, 1967; Morrissey, Goldman & Klerman (1980).
  • (6) Stimulation of parallel fibers or iontophoresis of acetylcholine excited P cells.
  • (7) Label was found widely distributed among all the organs except the nervous system and its rate of disappearance from the tissues paralleled its disappearance from the circulation.
  • (8) The bundles may lie parallel to the plasma membrane and to the long axis of the cell.
  • (9) Alterations in DNA synthesis induced by a single dose of cyclophosphamide in normal and tumorous tissues in vivo paralleled in many respects the changes seen when the more time-consuming techniques of the LI or granulocyte colony formation were employed.
  • (10) Dose distributions were evaluated under thin sheet lead used as surface bolus for 4- and 10-MV photons and 6- and 9-MeV electrons using a parallel-plate ion chamber and film.
  • (11) The influences of the inhibitor(s) for both tumours and in both culture systems were parallel.
  • (12) Parallel studies in vivo were carried out to determine the contribution of the phosphatidylserine decarboxylase pathway, relative to pathways utilizing ethanolamine directly, to the synthesis of brain ethanolamine glycerophospholipids.
  • (13) Plasma renin activities (PRA) and aldosterone concentrations increased in parallel over a wide range of plasma volume deficits produced in unanesthetized rats by extravascular administration of polyethylene glycol (PEG) solution.
  • (14) Combined study of lungs of 85 foetuses and newborns of various gestational age and 8 newborns dying during the first month of life showed the lung surfactant (LS) system to develop in parallel with formation of respiratory parts and lung capillary network.
  • (15) Ordering of these filaments into a parallel array is the basis of birefringence in the A region, and loss of birefringence is therefore a measure of decreased order.
  • (16) Comparing the regression lines of HR-QT and HR-QS2 separately for both groups, we found that both intervals decreased in parallel and the mean QT remained shorter than QS2 in both groups during exercise.
  • (17) Parallel changes in free T4 and the free T4 index indicate adequacy of the index in representing pineal-induced changes in free T4.
  • (18) In the course of its history, psychiatry has grown richer parallel to the development of its spatiotemporal system of the reference.
  • (19) Furthermore, the changes in both interstitial fluid and testicular venous blood levels of testosterone do not always parallel those in peripheral venous blood, suggesting that changes in testicular blood flow and peripheral clearance rates of testosterone may also be important in the control of circulating testosterone concentrations.
  • (20) On the basis of these data, the computer, upon the basis of a program specially developed for this purpose, automatically calculates the corresponding amount of negative-points, which parallels the severity of the joint changes, i.e.