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Use of cytogenetical methods in taxonomy of Arachnida (Arachnida)
Alaverdyan, Argam ; Šťáhlavský, František (advisor) ; Johnson Pokorná, Martina (referee)
This bachelor thesis deals with the use of cytogenetic methods in taxonomy of Arachnida. To understand this matter, we need to analyse available information about inter and intraspecific karyotype variability of individual orders. At the beginning of the thesis there is a description of cytogenetic methods used with Arachnida.They are used to gather the karyotype's fundamental information, such as the diploid number of chromosomes, chromosome morfology and possible occurence of sex chromosomes. Main part of the thesis is focused on describing karyotypes of selected orders (Amblypygi, Palpigradi, Pseudoscorpiones, Scorpions, Opiliones and Araneae) and considering the convenience of use of cytogenetic methods for their taxonomy based on these information. The thesis includes current number of described genera (species) of the orders, as well as a number of cytogenetically analyzed genera (species) for comparison.
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Genome size evolution in tropical tribe Globba (Zingiberaceae)
Pospíšilová, Monika ; Fér, Tomáš (advisor) ; Zedek, František (referee)
The variability of the genome size reaches several grades even within relatively close groups of plants. The study of the genome size in the phylogenetic context provides interesting results which characterize the evolution of the individual groups of plants. In this respect, tropical plants have yet not been studied. Tropical genus Globba (ca. 100 species) belongs to an economically significant family Zingiberaceae. The diversity centre is found in Thailand but it spreads from east India and southern China up to Indonesia and the Philippines. It is a polyploid complex which exists in two cytotypes within one genus (2n = 32 a 2n = 48); it is characteristic minimally in three out of seven distinguished sections. The aim of this thesis has been a reconstruction of the group phylogeny, discovering the role of the polyploid and evaluation of the genome size evolution of the Globba genus in the phylogenetic context. To this end, modern biosystematic methods were used (flow cytometry, chromosome counting, sequencing of the nuclear and chloroplast DNA regions). Many types of software and statistical methods were used to process and interpret the data. In this group, the genome size was measured for the first time. Out of 87 individuals, the smallest size was measured with Globba nuda (2C = 1.11 pg). The...
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Developmental defects of reproductive system in selected species of mammals
Vedralová, Petra ; Chmelíková, Eva (advisor) ; Krejčířová, Romana (referee)
Genital organs of males and females provide the reproduction and survival of the species. If the gonads or efferent tract are formed abnormally or missing, reproductive anomalies arise. Then development of female or male gametes are not normal and fertilization and pregnancy or sexual act can not be performed. It is in all livestock but also in all mammals.
Developmental disorders of reproductive system are usually inherited and they are passed from parents to offspring. Defects may occur at the chromosomal, gonadal or phenotypic level.
Monosomy and trisomy are serious disorders of chromosomal sex and they cause infertility of affected individual. Sex reversal is included among the defects of gonadal sex. Anomalies of phenotypic sex are hermaphroditism and pseudohermaphroditism. Hypoplasia of the ovaries and testes and frequent cryptorchidism belong to defects of the gonads. The most common anomalies of the efferent genital tract are aplasia of Müllerian and Wolffian ducts, hypospadia and diphallia.
Developmental defects are grave. Because of them the reproduction is not successful or even impossible. Animals in testing or breeding with disorders are excluded from breeding programme to defects not get among descendants.
The occurrence of genital tract defects causes reproductive disorders and infertility. It is linked closely with the economy mainly in livestock. So the breeding is lossy. Breeding is healthier and more successful if methods for describing are improved and selection is realized.
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