Frasnian (Upper Devonian) evidence for multiple origins of seed-like structures
نویسندگان
چکیده
منابع مشابه
investigating the feasibility of a proposed model for geometric design of deployable arch structures
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A paleomagnetic reinvestigation of the Upper Devonian Perry Formation: evidence for Late Paleozoic remagnetization
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Among the oldest convincing fossils of early vascular land plants are those of the Division Rhyniophyta. The members of this division consist of: (1) simple axes with cuticle, stomates, epidermis, cortex and a terete (circular) centrarch xylem (xylem development occurs from the center of the stem to the periphery), without well-developed appendages or roots; (2) simple, isotomous branching syst...
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In contrast to conventional splicing, which joins exons from a single primary transcript, trans-splicing links stretches of RNA from separate transcripts, derived from distinct regions of the genome. Spliced leader (SL) trans-splicing is particularly well known in trypanosomes, nematodes, and flatworms, where it provides messenger RNAs with a leader sequence and cap that allow them to be transl...
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ژورنال
عنوان ژورنال: Botanical Journal of the Linnean Society
سال: 1997
ISSN: 0024-4074
DOI: 10.1111/j.1095-8339.1997.tb01408.x