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Sexual dimorphism in the mouse olfactory system
Kuntová, Barbora ; Stopka, Pavel (advisor) ; Havlíček, Jan (referee) ; Žídek, Lukáš (referee)
Sexually dimorphic behaviour of the house mouse (Mus musculus musculus) relies on various physical and chemical cues, however, chemical signals are the most essential cues for individual recognition and in causing various priming effects on reproductive behaviour of the receiver. House mice belong to macrosmatic mammals, and thus, their sense of smell is highly developed and is able to recognize a wide spectrum of ligands from other individuals and from their surrounding environment. Volatile signals belong to organic compounds that are produced by most tissues, and may have harmfull effects on cells, and thus they are transported out of the body with lipocalin transporters where some of them may function as signals. These volatile signals are able to stimulate chemosensory neuronal receptors, and thus, yield particular responses in neural circuits. The ligand sensing has a differential effect upon males and females, however, it has not been shown yet in wild mice whether these differences are also caused by the variation in receptors and neural processing, or rather by differential expression of signals typical for each sex. The aim of this thesis was to perform comparative analysis of orofacial mucosal tissues to determine the specificity of expression of particular lipocalins. For the first time...
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Can birds manipulate sex ratio of their offspring?
Tomiška, Lubomír ; Kratochvíl, Lukáš (advisor) ; Fuchs, Roman (referee)
The aim of this study is a summary of existing knowledge about skewed sex ratio in birds. This controversial topic represents one of the most important questions of evolutionary ecology. We still miss consistence in finding ultimate causes just as proximate mechanisms although there was an expansion of experimental studies already in the last decade of the 20th century which was caused by an invention of the new technology in sex determination. On the other hand, there are many convincing proofs of skewed primary, secondary, tertiary and even quartenary sex ratio so the facultative manipulation or obligatory sex ratio bias is presumable. My Bachelor's thesis compares studies focused on the similar ultimate causes and tries to point out their deficiencies together with contributions to research of this topic. Observation of sex ratio includes many specifics which are mentioned in theoretical introduction. The second part offers potencial proximate mechanisms which could be responsible for sex ratio manipulation. Within the analysis of studies I found sex ratio manipulation of the first egg in clutch as common trend which could fit to selective ovum resorption as a proximate mechanism.
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Sexual dimorphism in the mouse olfactory system
Kuntová, Barbora ; Stopka, Pavel (advisor) ; Havlíček, Jan (referee) ; Žídek, Lukáš (referee)
Sexually dimorphic behaviour of the house mouse (Mus musculus musculus) relies on various physical and chemical cues, however, chemical signals are the most essential cues for individual recognition and in causing various priming effects on reproductive behaviour of the receiver. House mice belong to macrosmatic mammals, and thus, their sense of smell is highly developed and is able to recognize a wide spectrum of ligands from other individuals and from their surrounding environment. Volatile signals belong to organic compounds that are produced by most tissues, and may have harmfull effects on cells, and thus they are transported out of the body with lipocalin transporters where some of them may function as signals. These volatile signals are able to stimulate chemosensory neuronal receptors, and thus, yield particular responses in neural circuits. The ligand sensing has a differential effect upon males and females, however, it has not been shown yet in wild mice whether these differences are also caused by the variation in receptors and neural processing, or rather by differential expression of signals typical for each sex. The aim of this thesis was to perform comparative analysis of orofacial mucosal tissues to determine the specificity of expression of particular lipocalins. For the first time...
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Morphological changes of adult human face during aging
Čiháková, Lucie ; Velemínská, Jana (advisor) ; Blažek, Vladimír (referee)
Processes of biological changes of organism over time distinctly manifest themselves in a face morphology. The present study age changes are observed as shape and size changes of transversal dates of surface 3D virtual models of faces of 443 women and men (22-88 years old) devided into six age groups in decade. Differences in faces among each age group with respect to the sex were investigated and a sexual dimorphism and its gradual progress with the age using methods of geometric morphometrics (coherent point drift - dense correspondence algorithm, principal component analysis, per vertex t-test, shell-to-shell deviation). A significant difference among age categories was observedd both in shape as well as in form of the face. The faces of women and men were becoming wider with age and convexity was decreasing at the same time. A decline of the whole forehead and of the profile of the men's nose was observed, whereas the women's foreheadwas getting bevel due to the decline of the top part and a profile of the nose wasn't changed with the age. On contrary, the men's chin was unvarying with the age, while the women's chin was sliding out foward. There was observed a distinct decline in the front part of a upper jaw with the both sex. It was found out that after the seventh life decade the face gets...
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Can birds manipulate sex ratio of their offspring?
Tomiška, Lubomír ; Kratochvíl, Lukáš (advisor) ; Fuchs, Roman (referee)
The aim of this study is a summary of existing knowledge about skewed sex ratio in birds. This controversial topic represents one of the most important questions of evolutionary ecology. We still miss consistence in finding ultimate causes just as proximate mechanisms although there was an expansion of experimental studies already in the last decade of the 20th century which was caused by an invention of the new technology in sex determination. On the other hand, there are many convincing proofs of skewed primary, secondary, tertiary and even quartenary sex ratio so the facultative manipulation or obligatory sex ratio bias is presumable. My Bachelor's thesis compares studies focused on the similar ultimate causes and tries to point out their deficiencies together with contributions to research of this topic. Observation of sex ratio includes many specifics which are mentioned in theoretical introduction. The second part offers potencial proximate mechanisms which could be responsible for sex ratio manipulation. Within the analysis of studies I found sex ratio manipulation of the first egg in clutch as common trend which could fit to selective ovum resorption as a proximate mechanism.
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