Results 131 to 140 of about 6,984 (172)
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The coexistence of haploidy and diploidy in yeasts
Experientia, 1959In einigen Hefearten kommen haploide und diploide Zellen zusammen vor. Es wird angenommen, dass diese Koexistenz besondere Vorteile fur die Anpassung der Hefe an Milieux mit schnell wechselnden Bedingungen bietet. Die Vorteile der Haploidie und Diploidie erganzen sich, ohne dass sich die Nachteile der einen oder andern Form auswirken.
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Evidence for diploidy and mating in trypanosomes
Nature, 1980The question of whether any sexual process takes place at some stage of the life cycle of the trypanosome has often been raised and crosses between different drug-resistant strains have provided no convincing answer. Multinucleate forms of trypanosomes have been observed by electron microscopy but their significance and origin remain obscure.
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Sex and diploidy in Armillaria mellea
Experimental Mycology, 1978The life cycle and sexuality of Armillaria mellea are poorly understood. The mating behavior is atypical, and laboratory fruiting is rare. Genetic studies reported herein are based upon monosporous progeny from 27 distinct fruiting bodies and reveal A. mellea as a bifactorial heterothallic fungus.
Robert C. Ullrich, James B. Anderson
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Genetic Error, Sex, and Diploidy
Journal of Heredity, 1993Mathematical models and experiments on transformation are reported testing the hypothesis that sex and diploidy evolved as a DNA repair system. The models focus on the origin of diploidy and sex by studying selection between asexual haploids, sexual haploids, and diploids.
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Acta Biotheoretica, 1983
Under the influence of deleterious mutation and selection a population will reach equilibrium and contain individuals with [0, 1, 2 - - mutations.] This deterministic equilibrium distribution is exactly the same for asexual and sexual populations. The size of the optimal class (no), i.e. the class with the smallest number of mutations, is determined by
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Under the influence of deleterious mutation and selection a population will reach equilibrium and contain individuals with [0, 1, 2 - - mutations.] This deterministic equilibrium distribution is exactly the same for asexual and sexual populations. The size of the optimal class (no), i.e. the class with the smallest number of mutations, is determined by
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Haploidy or diploidy: which is better?
Nature, 1991Although the evolutionary advantages of sexual reproduction have been extensively discussed, much less attention has been paid to haploid and diploid phases of the sexual life cycle. The relative lengths of these phases differ greatly in various taxa, including as extremes those with one or the other phase reduced to a single cell. Here we consider the
A S, Kondrashov, J F, Crow
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On the potential for genetic variability in haplo-diploidy
Genetica, 1970Some theory pertaining to the genetic variability of haplo-diploid species is examined. Genetic variability due to wholly deleterious alleles is reduced in haplo-diploid species compared with species with both sexes diploid, but a random numbers experiment suggests that there is no a priori reason to believe haplo-diploidy reduces the likelihood of ...
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Haploidy, Diploidy, and Polyploidy
1980Haploidy is a general term for designating individuals or tissues (in mosaics) that have somatic cells with a gametic chromosome number (n).
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Diploidy, Population Structure, and the Evolution of Recombination
The American Naturalist, 2009In diploids, sex affects genetic variation through segregation and recombination. Several recent models on the advantage of recombination have focused on the effect of interaction between selection and drift in finite or structured populations; however, these models considered haploid organisms.
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Diploidy and repair of radiation damage in saccharomyces mutants
Mutation Research, 1973Abstract Diploid wild-type cells of Saccharomyces and cells homozygous for one of the single genes r s 1 , r s 2 of the two alleles of the r s 3 gene (rad 2 gene) were tested for their response to ionizing irradiation in the presence and absence of oxygen. Both immediate and delayed plating (agar-holding) techniques were used.
D, Averbeck, M, Ebert
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