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关键词： 动物生物学   竞赛试题   奥林匹克   实验   鳕鱼   考试   解剖   结构  

摘要： 总分:99分考试时间:90min共8题在本考试中,你将解剖鳕鱼(Gadus morhua),对你解剖和识别鱼的结构和器官的能力进行考察。另外,鱼不同结构的功能也会被考查。

关键词： 龙子祠泉域   底栖动物   水质生物学评价  

摘要： 2016年5月20—26日和7月25—30日设4个采样点,采用常规方法(用30cm×30cm的苏泊网采集底栖动物)调查山西省临汾市西南的岩溶大泉-龙子祠泉域底栖动物群落组成和生物学评价指标。调查期间共采集到4门7纲30属(种)底栖动物,其中昆虫纲(主要是蜉蝣目和毛翅目)和寡毛纲(主要是颤蚓类)个体数最多;官磑村底栖动物总个体数和总生物量最高,鲟养殖场次之。敏感种生物指数评价分析表明,临汾水厂和官磑村采样点水质为中度污染,鲟养殖场和入汾河口采样点水质为重度污染。龙子祠泉域水资源环境受到一定程度的污染。本研究结果表明,敏感种生物指数评价方法最适合该泉域水质环境评价。

关键词： 大型底栖动物   群落结构   水质评价   清江  

摘要： 研究清江利川段的大型底栖动物群落结构和评价水质,为合理实施该重点流域水环境分区管控和生态保护提供科学依据。2016年5月-2017年3月,在清江（源头至利川城下游）共设置5个采样点,开展了6次底栖动物群落结构调查,采用大型底栖动物科级水平生物指数（FBI）、底栖动物敏感性计分器指数（SIGNAL）进行水质生物学评价。底栖动物共检出5门8纲16目61科,其中源头采样点共采集9目,蜉蝣目数量占74.1%;临村庄采样点共采集7目,蜉蝣目数量占41.6%;近城区上、中、下采样点分别采集10、9和13目,优势目均为十足目,其数量分别占总量的73.5%、79.9%和54.5%。敏感类群蜉蝣目比例沿水流方向逐渐降低。基于底栖动物耐污性及其数量占比分析,该江段污染程度沿水流方向呈加重趋势。综合FBI和SIGNAL底栖生物指数与环境因子的拟合回归结果以及底栖动物污染敏感值,表明SIGNAL指数应作为该江段首选水质污染生物学评价指数。

关键词： genome editing   germline stem cell   in vitro spermatogenesis   spermatogonial stem cell   spermatogonial transplantation  

摘要： Background Spermatogonial stem cells (SSCs) are the origin of sperm and defined by their functions of colonization in the testis and spermatogenesis. In vitro manipulation techniques of SSCs contribute to a wide variety of fields including reproductive medicine and molecular breeding. This review presents the recent progress of the biology and manipulation technologies of SSCs. MethodsMain findingsResearch articles regarding SSC biology and technologies were collected and summarized. Dr. Ralph Brinster developed the spermatogonial transplantation technique that enables SSC detection by functional markers. Using this technique, cultured SSCs, termed germline stem (GS) cells, were established from the mouse. GS cells provide the opportunity to produce genome-edited animals without using zygotes. In vitro spermatogenesis allows production of haploid germ cells from GS cells without spermatogonial transplantation. The recent advancement of pluripotent stem cell culture techniques has also achieved production of functional GS-like cells in addition to male/female germ cells. ConclusionAlthough in vitro manipulation techniques of GS cells have been developed for the mouse, it appears to be difficult to apply these techniques to other species. Understanding and control of interspecies barriers are required to extend this technology to nonrodent mammals.

摘要： Mammals have evolved specialized brain systems to support efficient navigation within diverse habitats and over varied distances, but while navigational strategies and sensory mechanisms vary across species, core spatial components appear to be widely shared. This review presents common elements found in mammalian spatial mapping systems, focusing on the cells in the hippocampal formation representing orientational and locational spatial information, and 'core' mammalian hippocampal circuitry. Mammalian spatial mapping systems make use of both allothetic cues (space-defining cues in the external environment) and idiothetic cues (cues derived from self-motion). As examples of each cue type, we discuss: environmental boundaries, which control both orientational and locational neuronal activity and behaviour;and 'path integration', a process that allows the estimation of linear translation from velocity signals, thought to depend upon grid cells in the entorhinal cortex. Building cognitive maps entails sampling environments: we consider how the mapping system controls exploration to acquire spatial information, and how exploratory strategies may integrate idiothetic with allothetic information. We discuss how 'replay' may act to consolidate spatial maps, and simulate trajectories to aid navigational planning. Finally, we discuss grid cell models of vector navigation.

关键词： life history   Developmental Biology   Eggs   population biology   Biologists   Viviparity   Lizard   Anolis   Life cycle   Reptiles   Demography   Oviparity  

摘要： This research perspective focuses on three of the disciplinary areas that have engaged my interest as a professional biologist. My research first focused on life history evolution, but it expanded to include the evolution of viviparity, and developmental biology. My subjects are squamate reptiles, although I do hands-on research largely with lizards. A common theme of the research that I discuss here is the role of eggs and embryos in ecological and evolutionary studies and why that role may be critical to the resolution of important biological problems. In this perspective, I summarize highlights of my major research projects since 1971: 1) life history evolution of West Indian island and mainland Anolis lizards;2) long-term studies on the demography and egg survival of a small, r-selected Panamanian anole;3) ecological and physiological studies on the transition between oviparity and viviparity in Sceloporus;4) costs and benefits of the novel rigid-shelled egg of gekkotan lizards;and 5) embryonic adaptations to low oxygen availability in rigid-shelled eggs of gekkotan lizards. I put these projects in the context of my own developmental trajectory as a biologist;my research has shifted from population biology to embryonic development without breaking the connection between these seemingly disparate disciplines.

关键词： Social isolation stress (SIS)   hypothalamic-pituitary-adrenal (HPA) axis   Oxytocin   Neurotransmitters   Vasopressin   N-methyl-D-aspartate (NMDA)   Neurotrophicfactors (NTFs)   Early growth response transcription factor genes (egr)  

摘要： The brain is a vital organ, susceptible to alterations under genetic influences and environmental experiences. Social isolation (SI) acts as a stressor which results in alterations in reactivity to stress, social behavior, function of neurochemical and neuroendocrine system, physiological, anatomical and behavioral changes in both animal and humans. During early stages of life, acute or chronic SIS has been proposed to show signs and symptoms of psychiatric and neurological disorders such as anxiety, depression, schizophrenia, epilepsy and memory loss. Exposure to social isolation stress induces a variety of endocrinological changes including the activation of hypothalamic-pituitary-adrenal (HPA) axis, culminating in the release of glucocorticoids (GCs), release of catecholamines, activation of the sympatho-adrenomedullary system, release of Oxytocin and vasopressin. In several regions of the central nervous system (CNS), SIS alters the level of neurotransmitter such as dopamine, serotonin, gamma aminobutyric acid (GABA), glutamate, nitrergic system and adrenaline as well as leads to alteration in receptor sensitivity of N-methyl-D-aspartate (NMDA) and opioid system. A change in the function of oxidative and nitrosative stress (O&NS) mediated mitochondrial dysfunction, inflammatory factors, neurotrophins and neurotrophicfactors (NTFs), early growth response transcription factor genes (Egr) and C-Fos expression are also involved as a pathophysiological consequences of SIS which induce neurological and psychiatric disorders.

关键词： mammalian cells   CRISPR/Cas9   targeted integration   recombinase-mediated cassette exchange   transcriptome   clonal variation  

摘要： Mammalian cells are widely used to express genes for basic biology studies and biopharmaceuticals. Current methods for generation of engineered cell lines introduce high genomic and phenotypic diversity, which hamper studies of gene functions and discovery of novel cellular mechanisms. Here, we minimized clonal variation by integrating a landing pad for recombinase-mediated cassette exchange site-specifically into the genome of CHO cells using CRISPR and generated subclones expressing four different recombinant proteins. The subclones showed low clonal variation with high consistency in growth, transgene transcript levels and global transcriptional response to recombinant protein expression, enabling improved studies of the impact of transgenes on the host transcriptome. Little variation over time in subclone phenotypes and transcriptomes was observed when controlling environmental culture conditions. The platform enables robust comparative studies of genome engineered CHO cell lines and can be applied to other mammalian cells for diverse biological, biomedical and biotechnological applications.

摘要： Keesing reviews Australian Echinoderms: Biology, Ecology and Evolution edited by Maria Byrne and Timothy D. O'Hara.