Sökning: "sperm biology"

Visar resultat 1 - 5 av 36 avhandlingar innehållade orden sperm biology.

1. 1. Selection in sperm and its consequences : Exploring haploid selection, ageing and epigenetic effects in sperm

   Författare :Cosima Hermans Née Hotzy; Simone Immler; Göran Arnqvist; Mariana Wolfner; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sperm; evolution; selection; haploid selection; epigenetics; sperm-mediated effects; trans-generational effects; sperm ageing; sperm senescence;

   Sammanfattning : Sexually reproducing eukaryotes are typically going through a biphasic life cycle with a diploid and a haploid phase. Unlike in plants where selection on haploid pollen genotypes is well established, the possibility of selection occurring in animal sperm is currently not known. LÄS MER

3. 2. Sex, Sperm and Speciation : On sexual selection and fertility in hybridizing flycatchers

   Författare :Murielle Ålund née Podevin; Anna Qvarnström; Simone Immler; Leonie Moyle; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sperm biology; sexual selection; speciation; hybridization; cryptic female choice; fertility; Ficedula flycatchers; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : Sexual reproduction entails complex co-evolution between the sexes, necessary for successful fertilization, ensuring individual and population-level fitness. Interfertility is the main criterion for species definition and understanding speciation requires detailed studies of reproductive barriers. LÄS MER

4. 3. Sperm Membrane Channels, Receptors and Kinematics : Using boar spermatozoa for drug toxicity screening

   Författare :Alejandro Vicente Carrillo; Heriberto Rodríguez-Martínez; Karl-Eric Magnusson; Rudolf Rigler; Vesa Loitto; Stefan Arver; Linköpings universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Plasma membrane; membrane channels; membrane receptors; kinematics; 3Rprinciples; spermatozoa; boar.;

   Sammanfattning : Internal fertilization usually implies that a spermatozoon, with intact attributes for zygote formation, passes all hurdles during its transport through the female genitalia and reaches the oocyte. During this journey, millions to billions of other spermatozoa perish. LÄS MER

5. 4. Stochastic modelling and analysis of early mouse development

   Författare :Sofia Tapani; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; correlation; CUSUM; mouse; non-stationarity; pronucleus; stochastic differential equation; time series; wavelet decomposition; yeast; CUSUM;

   Sammanfattning : The aim of this thesis is to model and describe dynamical events for biological cells using statistical and mathematical tools. The thesis includes five papers that all relate to stochastic modelling of cells. LÄS MER

7. 5. Choice, competition, and interactions between episodes of sexual selection

   Författare :Charel Reuland; John Fitzpatrick; Ingo Schlupp; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; contest competition; sperm competition; mate choice; cryptic choice; sperm quality; reproductive status; social dominance; etologi; Ethology;

   Sammanfattning : Choice and competition are essential parts of evolutionary biology. In an effort to pass their genes from one generation to the next, animals may carefully choose their mating partners, and/or compete for access to mates. LÄS MER