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Chromosome Segregation: The orderly segregation of Chromosomes during Meiosis or Mitosis.

Oogenesis

JoVE 10906

In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal distribution of cell contents ensures that there are enough cytoplasm and nutrients to nourish the early stages of development. Second, during oogenesis, meiosis “arrests” at two distinct points: once during embryonic growth and a second time during puberty. In mammals, oocytes are suspended in prophase I until sexual maturation, at which point meiosis I continues under hormonal influence until an egg precursor cell is released into a fallopian tube. At ovulation, the precursor exits the ovary and, only if fertilization occurs, is stimulated to complete meiosis II and form a complete egg. Defects during oogenesis can result in severe consequences. In particular, problems with chromosome segregation during either meiosis I or meiosis II may lead to an embryo being aneuploid, meaning that it contains an abnormal number of chromosomes. Increased age elevates a woman

 Core: Reproduction and Development

Adenofection: A Method for Studying the Role of Molecular Chaperones in Cellular Morphodynamics by Depletion-Rescue Experiments

1Département de biologie moléculaire, biochimie médicale et pathologie, Faculté de médecine, Centre de recherche sur le cancer de l'Université Laval, 2Oncology, Centre de recherche du CHU de Québec, Université Laval, 3Laboratoire d'études moléculaires des valvulopathies (LEMV), Groupe de recherche en valvulopathies (GRV), Quebec Heart and Lung Institute/Research Center, 4Department of Surgery, Université Laval

JoVE 54557

 Biology

Digital Analysis of Immunostaining of ZW10 Interacting Protein in Human Lung Tissues

1Department of Hematology, Zhongnan Hospital of Wuhan University, 2Department of Thoracic Surgery, Renmin Hospital of Wuhan University, 3Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 4Department of Immunology, School of Basic Medical Sciences, Wuhan University, 5Department of Gastroenterology, Central Hospital of Wuhan, 6Department of Transfusion, Zhongnan Hospital of Wuhan University

JoVE 58551

 Cancer Research

Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes

1Department of Health, Animal Science and Food Safety, University of Milan, 2IRCCS. Istituto Ortopedico Galeazzi, 3PRC, CNRS, IFCE, Université de Tours, INRA, 4PAO, INRA, 5Clinique des Animaux de Compagnie et des Équidés, Université de Liège, 6University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania

JoVE 55242

 Developmental Biology
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