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  • evolution
  • Springer  (20)
  • 1975-1979  (20)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 13 (1975), S. 743-757 
    ISSN: 1573-4927
    Keywords: primate hemoglobins ; antigenicity ; evolution ; radioimmunoassay
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The antigenic properties of a number of chromatographically purified primate hemoglobins were compared to those of normal human hemoglobin using a sensitive radioimmunochemical procedure. The degree of inhibition of the antigen-antibody reaction with heterologous hemoglobins appeared to be related to the structural similarity of these proteins to the normal human hemoglobin immunogen. With the exception of the baboon hemoglobin, the antigenicity of the hemoglobins paralleled the phylogeny of the primates. The gorilla and chimpanzee hemoglobins were antigenically identical to normal human hemoglobin, whereas the gibbon and orangutan hemoglobins were substantially more variable. Of the Old World monkey hemoglobins examined, the baboon produced lower inhibition values, suggesting a greater degree of structural dissimilarity than other Cercopithecoidea hemoglobins, which is compatible with a greater rate of evolutionary change occurring in this protein. Using the known amino acid sequences of human and other primate hemoglobins, we have attempted to identify antigenic determinant areas of the proteins.
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  • 2
    ISSN: 1573-4927
    Keywords: cell size ; evolution ; gene action ; isoenzymes ; polyplodiy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract By use of cell size, protein and hemoglobin content, and enzyme activities as markers, it becomes apparent that in the course of evolution the gene expression of anciently tetraploid fish of the order Ostariophysi was diploidized, but no such regulatory mechanism has evolved in the phylogenetically tetraploid species of the order Isospondyli. This finding is discussed in terms of possible selective neutrality of tetraploid expression and the phylogenetic age of Isospondyli.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 14 (1976), S. 19-26 
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; ribosomal RNA genes ; cyprinid fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Phylogenetically diploid and tetraploid cyprinid fish species have cells of very similar volumes and protein contents. This finding has prompted us to postulate a regulatory system established during the evolution of the tetraploids leading to a diploid state of genic expression. It was proposed that this might be accounted for by a selective loss of ribosomal genes. RNA-DNA hybridization experiments, however, reveal a clear-cut 1:2 relationship of ribosomal DNA amounts between the diploid and the tetraploid species.
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  • 4
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; RNA content ; protein content ; enzyme activities ; Cyprinidae ; Isospondyli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The ratio of cellular RNA and protein content is about 1:1 between phylogenetically diploid and tetraploid species of the teleost family Cyprinidae, but is roughly in proportion to ploidy in species of the teleost order Isospondyli. Enzyme activities do not unequivocally comply with this scheme. These findings are discussed in view of the hypothesis that a regulatory mechanism which reduces genic activity has evolved in the tetraploid cyprinids but not in the tetraploid species of the order Isospondyli.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 56 (1977), S. 35-37 
    ISSN: 1573-5117
    Keywords: allometry ; skeleton weight ; vertebrates ; whales ; fishes ; bones ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The relation of skeleton weight to body weight with increasing size is compared for aquatic and terrestrial vertebrates. Due to the buoyancy of water, the skeleton weights of aquatic vertebrates (fishes and whales) vary in nearly direct proportion (exponent 1.0) to body weight; while the skeletons of terrestrial vertebrates occupy an increasingly greater proportion of total body weight as size increases (exponent greater than i. i) due to the necessity of supporting their weight on land.
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  • 6
    ISSN: 1573-5117
    Keywords: zoogeography ; predation ; evolution ; coevolution ; allometry ; Eriphia ; Nerita ; Gulf of California ; competition ; ecology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We measured maximum shell diameters and thicknesses of Nerita funiculata Menke and N. scabricosta Lamarck (Gastropoda: Neritidae), and claw sizes and carapace widths of the predatory crab Eriphia squamata Stimpson (Brachyura: Xanthidae), from the Gulf of California (Eastern Pacific). We also tested the ability of E. squamata to crush Nerita shells of various sizes. We compared this data on predator-prey counteradaptations with previously published data for congeneric species from the Western Atlantic and Indo-West Pacific regions. In relative abilities of the crabs to crush gastropod shells, and of the gastropod shells to resist such crushing, the Eastern Pacific species were ‘stronger’ than their counterparts in the Western Atlantic, but ‘weaker’ than their Indo-West Pacific congeners, indicative of an intermediate level of ‘faunal dominance’ or predator-prey ‘arms race’ escalation.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 26 (1977), S. 585-600 
    ISSN: 1573-5060
    Keywords: Solanum ; potato ; polyploidy ; 2n gametes ; sexual polyploidization ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The extent and pattern of polyploidy in the tuber-bearing Solanums varies among the many taxanomic series that have been identified in this subsection of Solanum. While several series appear to be entirely diploid, others exhibit a range of ploidy levels from 2x to 6x, and some contain only polyploid species. In many diploid, triploid and tetraploid species 2n gametes (gametes or gametophytes with the sporophytic chromosome number) have been detected. Both 2n eggs and 2n pollen occur. 2n gametes provide the opportunity for unilateral and bilateral sexual polyploidization. The genetic determination and consequences of sexual polyploidization strongly suggest that 2n gametes have been the major instrument in the polyploid evolution of the tuber-bearing Solanums. Somatic doubling of species and interspecific hybrids appears to be of very limited importance. New evidence for the occurrence of 2n eggs and 2n pollen in many species is reported, and data from the literature are added to illustrate the widespread distribution of 2n gametes throughout the subsection. A very high correlation is found between polyploidy and 2n gametes, and its significance is discussed. Proof is presented for the occurrence of alleles governing 2n pollen production in the cultivated tetraploids, providing additional evidence for the hypothesis that 2n gametes have been involved in their origin. Multiple unilateral and bilateral sexual polyploidizations are proposed for the origin of the cultivated tetraploids: this accounts for the large variability encountered in this group, which closely resembles that of the related diploids. Similar evolutionary pathways are hypothesized for the other polyploid complexes in the subsection. A scheme is proposed in which participation of both 2n and n gametes link together all ploidy levels in the tuber-bearing Solanums, thus overcoming the ploidy barriers and providing for gene flow throughout the sympatric species of the subsection.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 27 (1978), S. 665-675 
    ISSN: 1573-5060
    Keywords: Arachis hypogaea ; groundnut ; peanut ; putative genome donors ; evolution ; origin ; karyotypes ; amphidiploidy ; chromosome pairing ; Arachis batizocoi ; Arachis cardenasii ; phytogeography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Cytological studies of wild diploid Arachis species in the same section of the genus (sect. Arachis) as the cultivated peanut A. hypogaea L. show, with one exception, a karyotype characterized by the presence of 9 pairs of larger chromosomes and one pair of small (‘A’) chromosomes. The exceptional species A. batozocoi Krap. et Greg. has a more uniform karyotype. Interspecific hybrids between diploid species of similar karyotype have moderate to high pollen stainability, those involving A. batizocoi have zero pollen stainability and a very irregular PMC meiosis. Such infertile hybrids are the most likely to produce fertile, stable amphidiploids on doubling the chromosome complement. It is suggested that the cultivated peanut could have originated from such a sterile interspecific hybrid and on morphological and phytogeographic grounds the most likely genome donors are A. cardenasii (nomen nudum) and A. batizocoi of the species within section Arachis, which have been collected up to the present time.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Biochemical genetics 13 (1975), S. 45-51 
    ISSN: 1573-4927
    Keywords: gene action ; polyploidy ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In phylogenetically diploid and tetraploid Cyprinid fish species, erythrocyte volumes, protein contents, and mean activities of the enzymes LDH, 6PGD, and PGI per cell per active gene locus decline with increasing DNA contents. These findings are assumed to reflect an evolutionary tendency of polyploids to regulate their genic activity down to the level of the diploids.
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  • 10
    ISSN: 1573-4927
    Keywords: evolution ; polyploidy ; ribosomal RNA genes ; Isospondyli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Phylogenetically tetraploid species of the fish order Isospondyli generally have twice the mean ribosomal gene content as closely related species on the phylogenetically diploid level. Considerable intraspecific variation of rDNA amount was observed. These findings are discussed in view of the hypothesis that selective loss of ribosomal genes may account for diminishing genic activity in phylogenetically tetraploid organisms.
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