Oxygen supply limits the heat tolerance of avian embryos
نویسندگان
چکیده
منابع مشابه
Oxygen supply limits the heat tolerance of lizard embryos.
The mechanisms that set the thermal limits to life remain uncertain. Classically, researchers thought that heating kills by disrupting the structures of proteins or membranes, but an alternative hypothesis focuses on the demand for oxygen relative to its supply. We evaluated this alternative hypothesis by comparing the lethal temperature for lizard embryos developing at oxygen concentrations of...
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Oxygen concentrations in gelatinous egg masses of two species of opisthobranch gastropods were examined with microelectrodes. Embryos in central positions are near the limit of the oxygen supply required for development. This limit is approached despite a diffusion constant for oxygen in masses that is close to that in water. Closed-chamber respirometry shows that oxygen is consumed by masses i...
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The role of heat shock proteins (HSPs) in heat tolerance has been demonstrated in cultured cells and animal tissues, but rarely in whole organisms because of methodological difficulties associated with gene manipulation. By comparing HSP70 expression patterns among representative species of reptiles and birds, and by determining the effect of HSP70 overexpression on embryonic development and ha...
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ACCORDING to the hypothesis advanced by L0vtrup (1958) the supply of oxygen is one of the factors responsible for the determination of bilateral symmetry in amphibian embryos. The protein coat covering the outside of the egg is known to have a very low permeability (Holtfreter, 1943), and it was suggested in the hypothesis that the formation of the grey crescent consists in a stretching of this...
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In arid and semi-arid regions of the world bread wheat (Triticum aestivum L.) yield is highlylimited due to late season heat stress, mostly occurring during the reproductive phase. Hence thecurrent study was conducted to evaluate the effect of late season heat stress on grain yield andyield components of 20 spring bread wheat cultivars. For this purpose, a stripe block experimentincluding four ...
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ژورنال
عنوان ژورنال: Biology Letters
سال: 2019
ISSN: 1744-9561,1744-957X
DOI: 10.1098/rsbl.2019.0566