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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...

Body appendages of vertebrates are structures developing during embryonal stages through lateral outgrowth from main body axis. Despite their different composition and high diversity, all these structures are organised along three main axes. Antero-posterior polarization is the most significant in body appendage differentiation. These polarized differentiation changes are best understood in the limbs, where they are controlled by the organizing centre named zone of polarizing activity (ZPA). This centre interacts with another centre named apical ectodermal ridge (AER), which mainly governs limb outgrowth laterally from the body axis. ZPA produces Sonic hedgehog (Shh), along with other signalling molecules participating in the polarization. Shh is a key part of highly conserved signalling pathway common to polarized structures and is influenced by retinoic acid (RA), which plays role in the ZPA creation. ZPA activity stimulates secretion of fibroblast growth factors (Fgf) and bone morphogenic proteins (Bmp). All these signalling pathways ensure correct differentiation of appendages through interaction and concentration-dependent mechanisms. The goal of this thesis is to introduce the mechanisms of polarization in other appendages, such as external genitalia and branchial arch derivates to the reader,...

The model organisms like for example the fish Danio rerio has the ability to regenerate heart muscle during its whole lifespan. Compared to Danio rerio, the ability of heart regeneration differs in amphibians. While the newt has the ability to regenerate its heart tissue throughout its whole life, the Xenopus leavis loses its power when it goes through metamorphosis. The regenerative ability does not only differ between salamanders and claws. We can observe some differences between regeneration of Xenopus tropicalis and Xenopus leavis too. Compared to Xenopus leavis, Xenopus tropicalis has the ability to regenerate its heart tissue even in adulthood. Mammals have a very limited ability to regenerate their heart muscle. We can observe the ability to reverse heart damage in mice and humans for a very limited time of a few days after they are born. In adulhood they repair the heart muscle and the rich collagen scar is formed. It is vital that signaling pathways in regeneration of model organisms is researched further, so that the knowledge gained may help us in the treatment of heart injuries in humans. Key words: regeneration, heart muscle, repair, zebrafish, mammals, amphibians, heart development, vertebrates

Adenohypophysis is very important gland in vertebrate head. In general adenohypophysal development is described together with formation of the primary mouth. Adenohypophyseal placode migrates together with stomodeal placode in ventral direction. Stomodeal placode starts to invaginate and from oral ectoderm adenohyphyseal placode invaginates to form Rathke's pouch. Pouch is then separated from mouth and migrates towards the brain to make adult hypohyseal gland. Origin of adenohypophysis is therefore in oral ectoderm, but in some vertebrates species is this development little different and adenohypophysis can even be endodermal. In some vertebrate groups, like amphibians or fishes there's no sign of Rathke's pouch, thus early migrations of adenohypophyseal placode can be different. These differences are there maybe because these groups don't have shallow invagination of stomodeum like other vertebrates. There are some homological structures in other chordate groups, for example Hatshek's pit in amphioxus or neural gland in tunicates, these structures has, in contrast with vertebrates, endodermal origin. Key words: adenohypohysis, placodes, primary mouth, craniofacial development, Rathke's pouch, vertebrates

Vertebrate body appendages include a number of structures such as limbs, paired and median fins, the tail bud, the cloacal region, barbels or pharyngeal arch derivatives. Despite differences in form and function, these appendages share a number of developmental genetic mechanisms. Development of these structures is chiefly regulated by Fgf, Shh, Wnt, Tgf-β and retinoic acid signalling pathways, activity of transcription factors such as Hox or Tbx along with cis-regulatory elements controlling the genes in which these factors are encoded. A recurring feature shared by some of the herein discussed anatomical structures is a transient epithelial ridge whose activity influences production and proliferation of the adjacent mesenchyme. Some are also instructed by a signalling centre, which confers asymmetry to the structure. In this text, the various appendages are compared on the basis of their development in relation to tetrapod limbs and theories evaluating the emergence of vertebrate paired appendages. The fin fold theory and archipterygial theory are discussed in the light of recent data provided by evolutionary developmental biology. All together, this thesis evaluates shared and derived characteristics of vertebrate body appendages with the aim to provide a basis for the upcoming work on the role...

The fully-formed pharynx is for adult vertebrates indeed a vital structure. The pharynx provides two main functions - dealing with food and breathing. During embryonic development, pharynx is visible like a series of bulges on the lateral surface of the head. Embryonic development of the pharyngeal region starts with evagination of the endoderm to form the pouches, opposit to that the ectoderm invaginates to form the ectodermal clefts. Pharyngeal arches are formed after fusion of these epithelial layers, and pharynx is thus bordered by ectoderm from the inner, and endoderm from the outer side. Each pharyngeal arch consists of mesenchymal core of mesodermal and neural crest derived cells. All vertebrates develop through the so called phylotypic stage, being represented by the - pharyngula with the present pharyngeal arches. Accordingly, it was generally believed that development of the pharyngeal region is rather conservative in all vertebrates. My comparative analysis of pharyngeal development in different vertebrates species reveals that - only early embryonic formation of pharyngeal arches seems conserved, however, that later in development pharyngeal arches form various and diverse derivatives. Key words: Vertebrates, ectodermal fleft, endodermal pouch, pharyngeal arches, neural crest

Vertebrate dentition is a dynamic structure, which continuously renews its elements, the teeth. Continuous tooth renewal is enabled thanks to the presence of epithelial and mesenchymal dental stem cells. Epithelial stem cells are located in the dental lamina, which, together with the adjacent mesenchyme, takes part in regulation of the stem cells through a complicated signalling network. This network is responsible for the positioning, correct amount, inactivity, proliferation and differention of the stem cells. Vertebrate dentitions are morphologically diverse. However, their development is, to a certain extent, controlled by shared evolutionarily conserved mollecular mechanisms. For example, epithelial stem cells of all vertebrate groups examined so far express the transcription factor Sox2 and are shown to be regulated by signalling pathways, such as Wnt/β-catenin, Shh, Fgf and Bmp. Due to the rich diversity in dental lamina morphologies, the locations of presumptive stem cells correspondingly differ among vertebrates. This thesis summarizes current knowledge on dental stem cells in each lineage to identify shared and derived aspects of vertebrate dentitions.

Teeth represent a key evolutionary novelty of vertebrates. The dentition of the majority of extant vertebrates is present in the oral cavity associated with jaws and palate and/or in the pharyngeal cavity asscociated with the last pharyngeal arch. The ancestral state of the vertebrate dentition is considered to be presence of teeth through the whole oropharyngeal cavity. This state is however preserved only in few members of extant osteichthyans (for example bichir and latimeria). The other vertebrates gradually lost the pharyngeal dentition. The basal groups of actinopterygians meet the conditions of preservation of the ancestral states and are thus relevant for understanding the initial state in the evolution of vertebrate dentitions. On the other hand, some derived actinopterygian lineages contain members with the most specialized pharyngeal dentitions. This bachelor thesis concentrates on the description of pharyngeal dentitions accross vertebrates and focuses on members of basal actinopterygian lineages (bichir, sturgeon and gar), which from the point of view of dental evolution represent crutial, although neglected animals. Detailed description of pharyngeal dentitions of these animals will form a basis for the upcoming Diploma project. Key words: teeth, dentition, evolution, vertebrates, pharynx

This final thesis represents a complete guide to making didactic aids which can be used in teaching Biology in primary and secondary schools. It completes my bachelor thesis on the topic of the Taxidermy of selected species of birds with detailed photographs of individual steps made throughout the creation process of a dermoplastic mount. It also compares the creation of bird mounts to those of mammal mounts, and it deals with making skeletons of vertebrates. This final thesis acquaints the reader with the taxidermic species, and includes research of foreign literature focussing on interesting facts about mounts. The final output of this thesis is a series of mounts and assembled skeletons of different species of vertebrates, which can all be used as didactic aids at the Department of Biology and Environmental Studies, Faculty of Education, Charles University. KEY WORDS taxidermy, skeletons, vertebrates, didactic aids, dermoplastic mount

The prechordal plate is generally described as a population of axial mesendodermal cells that is formed during early embryonic development, in the rostral- most area of the vertebrate head. The population of the prechordal plate cells is specific for vertebrate, and evolution of the vertebrate head was one of the key steps during vertebrate evolution. During vertebrate embryogenesis, the prechordal plate cells are pushed by the growth of the forebrain, until only some small population remains in front of the notochord, which later differentiate into mesodermal cells. The precise morphogenesis of this prechordal mesoderm, differs across vertebrates, but in most vertebrates produces a pair of head cavities, which are called premandibular. Within the organogenesis of vertebrates, extrinsic eye muscles are formed from these mesodermal cells and cavities. The prechordal plate, however is also referred to as one of the important centers that control the formation of the vertebrate head during early embryogenesis, since its removal or inhibition of important signals caused various disorders and embryonic dead. This thesis aims to summarize the information on the formation and function of the prechordal plate cells during vertebrate embryogenesis. Key words: prechordal plate; prechordal mesoderm; head...

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

The topic of this thesis is dissection of vertebrate skeletons while using available and appropriate methods. The theoretical part is prepared based on Czech and foreign sources. For this part, there were used print publications, articles from journals and some Internet sources. It summarizes theoretical knowledge of the occurrence and anatomical structure of vertebrates. The practical part includes methodology involving collection, preservation and actual processing of animals. In detail, there are described possible methods of work that are evaluated and compared in the closing part. These proposed procedures are used for the selected representatives of vertebrates, in the individual chapter called - Results. The outcome of this thesis is a detailed guide with the procedures of chosen methods and preserved skeletons with a description of their characteristics. Powered by TCPDF (www.tcpdf.org)

In my thesis I focused on the comparison of teeth in mammals and man. I compared from the viewpoint of the composition of the glass and then also from the various types of teeth transformations within demands for food and, from the viewpoint of appearance of the individual teeth, and from the perspective transformations of individual teeth. There is also focus on access issues in a single series of textbooks of natural history and biology. Where we created a simple analysis contained in the table. Next, I created a proposal of project teaching on the subject of comparison teeth of mammals and man, that serves as a guide for other teachers.

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...

This thesis explores and classifies the capacities of computed tomography (CT) and mainly microcomputed tomography (micro-CT) in vertebrate research. The thesis pursues the application of the method in imaging the particular structures, tries to gain a knowledge as wide as possible about the studied tissues of vertebrates and about the resolution achieved with micro-CT and evaluates the optimal employment of this method. The aim of this thesis is to propose particular structures ideal for employment of this progressive method with high resolution in morphological, ecomorphological and phylogenetical context of research in vertebrate zoology. At present computed tomography is commonly used diagnostic method, which is employed not only in the medical and veterinary practice but also in biological research. The advantage of computed tomography is it's speed and the fact that it isn't invasive. CT and micro-CT can display mineralized tissues but also soft tissues with used of contrast agents. By micro-CT we create accurate three-dimensional projections of little structures. This can be helpful for example in research of spatially complex skulls and skeletons of even very small vertebrates. At first the thesis tries to map the principles of CT and mikro-CT, the history and the potential of the technique...

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...

The thesis consists of two main parts: a theoretical one which includes a separate chapter about the Jizera Mountains as a whole, introducing their geological structure, climate, botanical and zoological species and three public figures connected with the Jizera Mountains. The second part is a practical one. The first chapter which is divided into ten sub-chapters, introduces typical vertebrates, especially those which can be included in education at primary schools and grammar schools. The next chapter mentions nature trails which are later suggested as enriching elements in zoological excursions. These must follow the official paths within the nature conservation area. Certain thought in this thesis is also given to the SPA (Special Protection Area) established to protect the black grouse and the boreal owl. The last but one chapter involves selected centres of ecological education and other organisations organising programmes focused on vertebrates. Then there is classification of primary and secondary education with emphasizing a short survey of which biology textbooks are used at primary schools around Jablonec nad Nisou. Education at secondary schools is supplemented with international researches called PISA and TIMSS serving as a base for the last chapter, which is about enquiry based...

This thesis deals with the research of practical knowledge and skills of students of primary and secondary schools. It targets exploring of cognition of local common species of vertebrates (fish, amphibians, reptiles, birds and mammals). This thesis is focused on education in the nature. The results are presented in graphs and chart tables. Key words: Knowledge of local vertebrates, questionnaire survey, primary school, secondary school, high school, hobby group, genus name, species name.

"The possibilities of the Inquiry-based education (IBE) in the Vertebrate Biology" is the Thesis, whose aim is to chart the possibilities of the teacher in the use of vertebrates in the common lesson. In view of the Laws No.246/1992Coll. and No.114/1992Coll. the possibilities how to use the vertebrates are very restricted. Even a common vertebrate-breeding in a class room is entirely excluded. The method of observation seems to be the most suitable one. The whole theoretical part of the Thesis deals with this method as well as the other methods and already existing tasks of IBE dealing with the vertebrates. There are three new complex tasks in the practical part of the Thesis: "Snapshot Serengeti get to know the fauna of the National Serengeti Park", "Birds in the Winter"and "Birds in the Winter - Excursion to zoo".

This thesis is a part of the project aimed at sequencing the genome and transcriptome of the bank vole (Clethrionomys glareolus). The role of natural selection in the evolution of mitochondrial DNA (mtDNA) has been subject to much discussion; while some studies did not provide evidence that selection affected the phylogeography of the studied species, other considered adaptive evolution important. The bank vole is the key model we use to study the adaptation to climate change. As with other species, the phylogeography of the bank vole has been based on the variation of a small part of mtDNA. The goal of the thesis was to sequence the entire mitochondrial genome for representatives of all main mtDNA lineages of the bank vole using the Sanger and Illumina technologies, and to assess the role of selection and adaptation in the evolution and phylogeography of this species. The adaptive evolution in mtDNA probably was not the main driving force during the postlacial colonization of Europe. However, signatures of adaptive evolution have been found - an amino acid change with possible functional consequences in one gene and an excess of radical changes in physical- chemical properties of amino acids in populations at the latitudinal (northern and southern) extremes of the bank vole distribution. Key...

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 (www.tcpdf.org)

Germ free (axenic) animals are individuals reared under specific conditions preventing their contact with surrounding microorganisms. Some of the features observed in these individuals vary from those observed in naturally colonized counterparts. These differences probably reflect the influence of presence of a complex intestinal microbial population in the intestine, which influences important physiological functions of the host body by various mechanisms. Thus, nature of these differences allows to study relationship of the host, vertebrate in this case and its microbiota, which evolved into a complicated system of interactions providing relatively stable coexistence. Germ free research of this relationship is focused on interactions between microbiota and host's immune system, metabolism, morphology of digestive tract and behavior. This thesis provides summary of research outcomes on previously mentioned topics. Powered by TCPDF (www.tcpdf.org)

The study was aimed to obtain basic information about the distribution of intestinal parasites of mammals and birds in Svalbard. Faeces of different species were used to detect intestinal parasites. All samples were collected during two seasons and examined by microscopic methods and molecular diagnostic was used for detection of microsporidia, cryptosporidia, coccidia and giardiae.

Sound expressing is common for a big amount of animal species, mostly when communicating with individuals of their own or other species. Acoustic communication can be used especially in situations or in the environment where an individual does not see a signal receiver well (confusing environment, at night or long distance). It's well-known that the individual species have their own characteristic acoustic expressions. However, these can differ also within the species itself, either in time or in space. This study is concerned just with variability of inter-species vocal communication of all vertebrates in space. Its purpose is to map at which animal species vocalization vary in space. Furthermore, it deals with searching for causes of origin of this variability, such as genetic differences among particular groups of populations, environmental and learning effects etc. within various animal species. In the last part, it tries to answer the question whether the spatial variability of acoustic signals could influence separation of new species and thus have evolutionary consequences.

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...

Animals that live in different altitudes are exposed to different environmental conditions. Among others, ambient temperature, precipitation and availability of resources change along an elevational gradient. An adaptation of vertebrates to these conditions causes that in populations or species that live in higher altitudes individual ecological traits evolves to a different degree than in those that live in lower altitudes. Studies suggest that vertebrates that live in higher altitudes usually have shorter active and breeding season, reach larger body size and weight, have slower growth, have smaller clutches or litters, mature at later age and live longer. However, almost in all traits we can find opposite trends. In all vertebrate groups similar changes in traits occur. However, some traits aren`t explored in all groups, for example grow of birds and mammals. Powered by TCPDF (www.tcpdf.org)

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

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.

The aim of the diploma thesis was to create didactic materials with motivation components that would use area of exhibition ?Třeboňsko ? landscape and people? in teaching vertebrate zoology. These materials are intended for pupils of basic and secondary schools, mainly in surrounding the town Třeboň. Diploma thesis includes the conceptual and structural analysis of vertebrate topic in biology schoolbooks. The materials are divided into two groups. First group are information worksheets and worksheets which are usable in the exhibition. Second group are proposals of excursions. Materials have own tasks and questions. Some of tasks were practically tested. Diploma thesis was solved in the project GA JU 065/2010/S.

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.

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...