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71.
Progeny produced from Bombina bombina, B. variegata, and field-collected interspecific hybrids have been analyzed for the inheritance of five enzyme loci, which are fixed for alternate alleles in the parental species. Lactate dehydrogenase (Ldh-1), NAD-dependent malate dehydrogenase (Mdh-1), creatine kinase (Ck), adenylate kinase (Ak), and glucosephosphate isomerase (Gpi) are all inherited in a Mendelian manner as codominant alleles at nuclear loci. Both parental alleles are equally functional in artificial F1 hybrids (female B. bombina×male B. variegata) at each of the loci studied. No linkage between any pair of loci was observed. Discovery of this inherited biochemical variation combined with a technique for assaying individual genotypes without killing the animals makes feasible studies of hybrid population structure heretofore impossible.This work was partly supported by the Polish Academy of Sciences within the project MR-II/6. 相似文献
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Examination was made of the effect of alternating light and darkness (LD 12:12) and constant light (LL) conditions on length of development and fecundity of the moth, Ephestia kuehniella. It was found the conditions applied cause acceleration of larval development on an average by 3 days in comparison with development under constant darkness conditions (DD). The fecundity of the insects examined decreases considerably under the experimental conditions.When pharate adults are kept in light for 18 hr per 24-hr period on the 6th to 7th day of their development, males incapable of fertilizing females are produced. 相似文献
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The venom that Chelonus sp. near curvimaculatus injects into each parasitized Trichoplusia ni egg is entirely injected within the first 8 s of the 19-s oviposition period, before deposition of the parasitoid egg that is injected during the final 1-2 s of the oviposition. The parasitization factor, causing precocious metamorphosis of the host, is injected after the venom, but before the parasite egg. The venom by itself does not cause developmental redirection of the host. Chelonus venom proteins are very stable in the host egg during the first 2 days of egg development. Then, on the last day before hatching, they are rapidly degraded by the proteolytic enzymes appearing in 3-day-old T. ni eggs. Among those that degrade the venom proteins are serine-type proteinases, and at least one seems to be a trypsin-like enzyme. 相似文献
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Hanna Grajek Regina Drabent Grażyna Żurkowska Czesław Bojarski 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,801(3):456-460
The electronic absorption spectra of the flavomononucleotide (FMN) in aqueous solution and in glycerine-water solution with change of the dye concentration have been measured. The FMN dimer absorption spectrum, monomer absorption spectrum, dimerization constant K and molar fraction of the monomer were calculated. It was found that FMN dimerization constants in aqueous solution were Ka = 118.0 l/mol and in glycerine Kg = 20.5 l/mol. In the region of the monomer absorption band two dimer absorption bands appear, in accordance with the Kasha molecular exciton theory. 相似文献
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Plant Ecology - The impact of exotic annual Impatiens glandulifera on invaded European vegetation is ambiguous; there are studies reporting considerable negative as well as weak or even no impact... 相似文献
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