Systematic-ecological aspects of Radiolaria with special reference to Acantharia
نویسندگان
چکیده
منابع مشابه
Molecular phylogeny and morphological evolution of the Acantharia (Radiolaria).
Acantharia are ubiquitous and abundant rhizarian protists in the world ocean. The skeleton made of strontium sulphate and the fact that certain harbour microalgal endosymbionts make them key planktonic players for the ecology of marine ecosystems. Based on morphological criteria, the current taxonomy of Acantharia was established by W.T. Schewiakoff in 1926, since when no major revision has bee...
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هدف از این تحقیق بررسی برخی عوامل ادراکی واحساسی یعنی استفاده از شیوه های یادگیری زبان ، انگیزه ها ونگرش نسبت به زبان انگلیسی در رابطه با زمینه زبانی زبان آموزان می باشد. هدف بررسی این نکته بود که آیا اختلافی چشمگیر میان زبان آموزان دو زبانه و تک زبانه در میزان استفاده از شیوه های یادگیری زبان ، انگیزه ها نگرش و سطح مهارت زبانی وجود دارد. همچنین سعی شد تا بهترین و موثرترین عوامل پیش بینی کننده ...
15 صفحه اولDiversity, Ecology and Biogeochemistry of Cyst-Forming Acantharia (Radiolaria) in the Oceans
Marine planktonic organisms that undertake active vertical migrations over their life cycle are important contributors to downward particle flux in the oceans. Acantharia, globally distributed heterotrophic protists that are unique in building skeletons of celestite (strontium sulfate), can produce reproductive cysts covered by a heavy mineral shell that sink rapidly from surface to deep waters...
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ژورنال
عنوان ژورنال: Bolletino di zoologia
سال: 1978
ISSN: 0373-4137
DOI: 10.1080/11250007809440123