National Repository of Grey Literature 57 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Study of differential potential of germ stem cells in vitro in higher vertebrates
Smolík, Ondřej ; Krylov, Vladimír (advisor) ; Krulová, Magdaléna (referee)
Spermatogonial stem cells are unipotent male germ cells which provide spermatogenesis during the whole life. In 2004, an important experiment was conducted. During in vitro cultivation mouse spermatogonial stem cells gained the characteristics of embryonic stem cells, pluripotency by all means. Those cells had the feature to spontaneously differentiate into all three germ layers, endoderm, ectoderm and mesoderm. They also could pass its genetic information to the next generation and they could give rise to teratomas. By this event, experiments started on other vertebrates including rodents, domestic animals and also human. Differentiation of these cells can be directed in vitro to generate specific cell types. On base of these facts, spermatogonial stem cells are alternative source of pluripotent cells which possess many applications in life sciences. The purpose of this thesis is to summarize actual knowledge about differentiation potential in vitro of spermatogonial stem cells in higher vertebrates and try to identify tendencies which they prefer during differentiation, if they exist. Powered by TCPDF (
Returning Vertebrate Species as a Topic of Environmental Education
Hartlová, Adéla ; Andreska, Jan (advisor) ; Chocholoušková, Zdenka (referee) ; Urban, Peter (referee)
The presented thesis deals with the relationship between humans and animals that return to the Czech Republic due to various circumstances, especially national protection, and protection within the European Union. This is a group of animals that have been exterminated from the Czech wilderness for various reasons and upon their return cause damage, arouse fear and cause controversy. The spontaneous return and reintroduction of some vertebrate species is, therefore, considered a controversial topic at present because we are facing reintroduced and returning species more and more frequently. This is why people should ideally be introduced to this topic at primary schools, where the information is presented in a clear and didactic way, rather than later on, for example, in the context of various attitudes-raising campaigns. For this reason, this research was performed at primary schools, grammar schools and secondary vocational schools training future foresters and fishermen, in order to determine what pupils' attitudes towards these returning or reintroduced vertebrate species are and what can influence these attitudes. This research was carried out in the form of a questionnaire survey with analyses in Jamovi and Statistica 14. Subsequent analyses of the data revealed that students have generally...
Mechanisms of the cell migration in the early embryonic development of vertebrates
Kováčiková, Petra ; Krylov, Vladimír (advisor) ; Černý, Robert (referee)
Cell migration, usually seen as a relatively well understood phenomenon, is involved in many aspects of multicellular organisms. While given a major attention due to its part in physiological processes, such as immune response, wound-healing and regeneration, or pathologies like progression of metastatic cancers, its key role in the body plan formation is far less understood and often overlooked. During a process called gastrulation, precursors of three germ layers - superficial ectoderm, inner endoderm and medial mesoderm - are arranged according to their fate, generating a three-layered embryo, a hallmark of triblastic vertebrates. The onset of this highly coordinated step of early embryonic development is accompanied by fine-tuned cell migration, which needs to be downregulated in adults in order to maintain a homeostasis. The cells forming gastrulating embryos collectively undergo a set of behaviors termed morphogenetic movements whose features - partially comparable to ones observed on cells migrating in culture - are shared among vertebrate species, providing valuable insights into "hidden homology" and phylogenetic relationships. Research focusing on regulation and mechanisms of morphogenesis is mostly conducted using Xenopus laevis as a model organism, extrapolating results to higher...
Breeding small vertebrates in primary schools - Comparison from selected EU countries
Bártlová, Zuzana ; Andreska, Jan (advisor) ; Hanel, Lubomír (referee)
This works main topic is raising vertebrates at school. It includes their problems and benefits. Its aim is to create a clear text offering information to people interested in this activity. The questionnaire method was used to find experiences of teachers from both the Czech Republic and abroad (Norway, Poland, Spain). The result of the research is a survey, which offers a survey of the experiences and views of respondents. Key words: breeding, school, vertebrates, Norway, Poland, Spain, Czech Republic
Ontogeny, evolution & homology of cement glands and attachment organs in lower vertebrates
Minařík, Martin ; Černý, Robert (advisor) ; Ráb, Petr (referee) ; Buchtová, Marcela (referee)
Aquatic larvae of many vertebrate lineages develop specialized, cranially located cement or attachment glands which allow them to remain attached to a substrate by means of polysaccharide secretion. The larvae can thus remain still and safe in well-oxygenated water out of reach of any predators until the digestive and locomotory apparatus fully develops. Xenopus cement gland is the most thoroughly studied example of this type of glands, since it was used as a model for the anteriormost patterning of the developing head. Based on shared expression patterns of key transcription factors and a similar ectodermal origin it has been repeatedly suggested that Xenopus cement gland is homologous to adhesive organs of teleosts and adhesive papillae of ascidians. The lack of comprehensive knowledge on this type of glands in other lineages however rendered any considerations of homology among such a distant lineages rather inconclusive. In the present work I have focused on a detailed study of the cement glands and other corresponding structures in three representatives of basal actinopterygian lineages: Senegal bichir (Polypterus senegalus), sterlet (Acipenser ruthenus), and tropical gar (Atractosteus tropicus). Using a combination of in vivo fate-mapping approaches with a Micro-CT imaging of cranial endoderm...
Neural crest biology with respect to diversity of vertebrates
Štundl, Jan ; Černý, Robert (advisor) ; Němec, Pavel (referee)
Neural crest is an extensively migrating population of cells that arise during early development of vertebrate embryos. It provides a huge variety of different cell types that generate new tissues which occur only in vertebrates. Neural crest cells together with the mesoderm participate on the formation of the head of vertebrates, which is viewed as one of the most important innovations in the evolution of vertebrates. Thanks to their skeletogenic potencial neural crest cells are percieved as a key factor causing massive craniofacial diversity. The aim of this thesis was to get acquainted with the population of neural crest cells and try to understand its importance for the evolution of vertebrates and especially for generating craniofacial diversity.
Influence of body size and temperature on cardiac function in vertebrates
Špičák, Luboš ; Starostová, Zuzana (advisor) ; Marková, Ivana (referee)
Heart, as main driving unit of circulatory system of vertebrates, ensure a great number of body functions by constant circulation of blood in every individual. This body functions are provided by transposport of energy in various forms and by transport of chemical substances. Number of these body functions are absolutely necessary in each momemnt of the lifetime. If we describe metabolism as speed of all reactions in body, then circulatory system is one of the key means to reach it. Metabolic rate increases with two basic factors, body mass and body temperature. It's not proportional relationship, but allometric increase is conditioned by power law. In addition, this exponential relationship is limited, in case of body temperature, by temperature range specific for each living organism. It would be expected that changes in size of body and body temperature might have strong influence to quality and function of circulatory systém and heart itself. However, metabolism is significantly influenced by some another factors like quality of adjacent surrounding. Organisms belonging to vertebrates habitated great number of various enviroments and they developed lots of adaptations to survive there. This adaptations include significant changes in cardiac architecture and heart functions. The aim of this work...
Developmental morphogenesis of attachment organs in lower vertebrates
Minařík, Martin ; Černý, Robert (advisor) ; Buchtová, Marcela (referee)
Adhesive organs are widespread structures among vertebrate larvae. They allow the larvae to attach to a substrate, so that the time for the development of mouth or motoric apparatus could be prolonged. Similar structures in ascidians, larvaceans and lancelets are known too. Thus, it might be hypothesized that the presence of some type of adhesive gland could indeed represent the ancestral state for chordate larvae. Interestingly, however, whilst in most species these glands take their developmental origin in ectodermal layer, in bichir, a member of a primitive actinopterygian lineage, their origin was suggested to be endodermal already at the beginning of 20th century. Since then, however, the former study has become almost forgotten and even recent analyses do not come with new findings on this topic. Because of the essential importance of study of bichir cement glands for understanding the relationship between these structures among chordates, I have decided to focus on this subject. To obtain appropriate comparative data Xenopus, Weather loach and Ribbed newt embryos were included in this study as well. By using combination of immunohistochemical and histological techniques the endodermal origin of cement glands in bichir was proven and their morphogenesis was described into considerable details. The...
Study of differential potential of spermatogonial stem cells via transplantation in vertebrates
Kodedová, Barbora ; Krylov, Vladimír (advisor) ; Pšenička, Martin (referee)
Spermatogonia, or spermatogonial stem cells are necessary to maintain male fertility. In the complex process of ongoing spermatogenesis in the testes these pluripotent stem cells proliferate and differentiate into sperm cells. In 1994 the first spermatogonial transplantation technique was described in rodents to allow the study of male germ cells. The following series of studies of intra- and inter-species transmission of testicular tissue revealed the regenerative capacity of transplanted spermatogonial stem cells and their possible usage. Recently, spermatogonia transplantation systems are developed in many vertebrates making it possible to study the development of sperm as well as artificial production of male and female gametes derived from germ cell donors. The differentiation potential of spermatogonial stem cells enabled the creation of transgenic organisms by genetic manipulation of isolated spermatogonia and subsequent transplantation into a suitable recipient. Spermatogonial transplantation in the future may find their application in regenerative medicine, the treatment of disorders of spermatogenesis, or serve to preservation of genetic stock of endangered species.
Made of three dimensional teaching aids
Strnadová, Kristýna ; Řezníček, Jan (advisor) ; Novotný, Petr (referee)
This work deals with vertebrates bone preparation of birds and mammals to enrich the science classes at secondary school. It also expands the collection of vertebrate skeletons at the department of biology and enviromental studies. The display would be enriched by Talpa europea, apodemus sylvaticus, rattus rattus, alectoris rufa and skulls of octodon degus. In this work there are described ways how to prepare taxidermy and bone preparation is described from the beginning of collecting vertebrates, then methods of preparation (maceration, hot water maceration, dermestidae bettles and more) including degreasing and bleaching and final treatment not the get it damaged by insect. This work is completed by survey. There are involved teachers of biology at elementary schools. The idea of questionnaire was to find out what's equipment like and how often do teachers use nature products to enrich the lessons. Key words - taxidermy, osteological preparation, birds, mammals

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