Comparative analysis of smooth muscular tissue of bronchi and of rectal pelvic region was performed using electron microscopic and cytophotometric methods. Smooth myocyte population of organs studied were demonstrated to include three cell types: small, medium and large ones. The population structure of smooth muscular tissue has similar pattern in bronchi and intestine, despite the established statistically significant diversity in their smooth myocyte volumetric parameters. Small smooth myocyte subpopulation was found to contain the cells considered to be smooth muscular tissue cambial elements by their ultrastructural and cytophotometrical characteristics.
Smooth muscle tissue
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Fossil Record
Armour
Tetrapod (structure)
Vertebrate paleontology
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Evidence of detailed brain morphology is illustrated and described for 400-million-year-old fossil skulls and braincases of early vertebrates (placoderm fishes). Their significance is summarized in the context of the historical development of knowledge of vertebrate anatomy, both before and since the time of Charles Darwin. These ancient extinct fishes show a unique type of preservation of the cartilaginous braincase and demonstrate a combination of characters unknown in other vertebrate species, living or extinct. The structure of the oldest detailed fossil evidence for the vertebrate eye and brain indicates a legacy from an ancestral segmented animal, in which the braincase is still partly subdivided, and the arrangement of nerves and muscles controlling eye movement was intermediate between the living jawless and jawed vertebrate groups. With their unique structure, these placoderms fill a gap in vertebrate morphology and also in the vertebrate fossil record. Like many other vertebrate fossils elucidated since Darwin's time, they are key examples of the transitional forms that he predicted, showing combinations of characters that have never been observed together in living species.
Sociology of Education
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Vertebrate paleontology
Living fossil
Brain tissue
Fossil Record
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Collagens from the skins of Sepia officinalys, an invertebrate, mollusc and Cybium guttatum a marine fish (lower vertebrate) were extracted. The aggregation of platelets by these collagens was investigated and compared with the induction of platelet aggregation by vertebrate collagen. The collagens from invertebrate and lower vertebrate were found to induce platelete aggregation as actively as vertebrate collagen. The lower vertebrate collagen showed highest aggregation when compared to other collagens suggesting that it can be used as a better hemostatic agent.
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The vertebrate origin and evolvement has always played core role of evolution and life science. Recently, there have been vital Advances in vertebrate origin and evolvement. A pipiscid-like metazoan fossil: Xidazoon stephanus, hemichordate fossil: Yunnanozoon and Haikouella, unrochordate fossil: Cheungkongella ancestralis, craniate-like/ cephalachordate chordate fossil: Cathaymyrus haikouensis and zhongxiniscus intermedius and vertebrate fossil: Myl-lokunmingia fengfiaoa and Haikouichthys ercaicunensis had been found in Yunnan Chengjiang Cambrian fauna and have been being investigated by many scholars. This demonstrates that these fossil are intermedial transitional types that e-volved from invertebrate to vertebrate.Therefore, a comparatively integrated evolutive tree was described. D-G Shu in early life institute of Northwest University proposed the hypothesis that there were five steps in vertebrate origin based up-on series of investigations concerning metazoan soft-body fossils closed vertebrate headstream. Namely, there was key-stone original step before the four steps in vertebrate origin. That is to say, those vetulicolia fossils unearthed in Yunnan Chengjiang Cambrian fauna are likely intermedial transitional types that evolved from protostomes to deuterostomes.This paper reviewed Advances in vertebrate evolved from invertebrate.
Chordate
Vertebrate paleontology
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Abstract Rapid vertebrate diversity evaluation is invaluable for monitoring changing ecosystems worldwide. Wild blow flies naturally recover DNA and chemical signatures from animal carcasses and feces. We demonstrate the power of blow flies as biodiversity monitors through sampling of flies in three environments with varying human influences: Indianapolis, IN and two national parks (the Great Smoky Mountains and Yellowstone). Dissected fly guts underwent vertebrate DNA sequencing (12S and 16S rRNA genes) and fecal metabolite screening. Integrated Nested Laplace Approximation (INLA) was used to determine the most important abiotic factor influencing fly-derived vertebrate richness. In 720 min total sampling time, 28 vertebrate species were identified, with 42% of flies containing vertebrate resources: 23% DNA, 5% feces, and 14% contained both. The species of blow fly used was not important for vertebrate DNA recovery, however the use of female flies versus male flies directly influenced DNA detection. Temperature was statistically relevant across environments in maximizing vertebrate detection (mean = 0.098, sd = 0.048). This method will empower ecologists to test vertebrate community ecology theories previously out of reach due practical challenges associated with traditional sampling.
Environmental DNA
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