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Early Development of Vertebrates. Fish, Birds, and Mammals. Zebrafish Development. Cleavage in Zebrafish. What kind of cleavage occurs in fish?. Cleavage in Zebrafish. At the time of the mid-blastula transition three cell populations form: yolk syncytial layer (YSL) enveloping layer (EVL)
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Early Development of Vertebrates Fish, Birds, and Mammals
Cleavage in Zebrafish • What kind of cleavage occurs in fish?
Cleavage in Zebrafish • At the time of the mid-blastula transition three cell populations form: • yolk syncytial layer (YSL) • enveloping layer (EVL) • deep cells • What is the importance of each?
Gatrulation in Fish • How does gastrulation begin?
Gastrulation in Fish • What is the germ ring in the developing embryo? • How does hypoblast form?
Gastrulation in Fish • What is the role of convergence and extension?
Axis Formation in Fish • How has it been demonstrated that the embryonic shield is critical to dorsal-ventral axis formation? • What structures form from it?
Axis Formation in Fish • How does notocord induce neural structures from overlying ectoderm?
Axis Formation in Fish • Where is the Nieuwkoop center and how does it function? What determines the anterior-posterior axis?
Cleavage in Birds • What kind of cleavage occurs in birds?
Cleavage in Birds • What is the area pellucida, area opaca and subgerminal cavity?
Gastrulation in Birds • How is the two-layered blastoderm formed?
Gastrulation in Birds • What is the primitive streak?
Gastrulation in Birds • What is important about the primitive groove? • the primitive knot or Henson’ node? • How does the primitive streak define the embryonic axes?
Gastrulation in Birds • What is the fate of cells migrating through the primitive streak?
Gastrulation in Birds • What happens to the primitive streak?
Gastrulation in Birds • What is needed to complete the process of gastrulation?
Axis Formation in Birds • How does the pH influence the formation of the dorsal-ventral axis? • How do we know this is true?
Axis Formation in Birds • How goes gravity influence formation of anterior –posterior axis?
Axis Formation in Birds • How does formation of Nieuwkoop center in birds compare with amphibians?
Axis Formation in Birds • From where does the “organizer” in the chick form?
Axis Formation in Birds • How is left-right axis formed? • How has this been demonstrated experimentally?
Early Mammalian Development • What makes mammalian cleavage unique?
Early Mammalian Development • What is compaction and when does it occur?
Early Mammalian Development • How is trophoblast different from inner cell mass? • How does blastocyst form from morula?
Early Mammalian Development • What enables the blastocyst to attach to the uterus?
Gastrulation in Mammals • Development is internal. What modifications to the anatomy does this involve?
Gastrulation in Mammals • gastrulation begins at the posterior end of the embryo What appears to control cell migration and specification?
Gastrulation in Mammals • precursors of ectoderm are anterior to primitive streak • human hypoblast cells are replaced by endoderm precursors
Extraembryonic Membranes • How does placenta provide nutrients and oxygen to fetus?
Anterior-Posterior Axis Formation • Where are the two signaling centers located in the mammalian embryo?
Anterior-Posterior Axis Formation • How is mouse node and AVE similar to chick and frog organizer tissues?
Anterior-Posterior Axis Formation • What kind of interactions occur between visceral endoderm and epiblast in mice?
Anterior-Posterior Axis Formation • What is believed to be the role of the Hox genes?
Anterior-Posterior Axis Formation • What kind of evidence has enabled us to break the Hox gene code? • knockout experiments • experiments with retinoic acid • comparative anatomy studies
Anterior-Posterior Axis Formation • What was shown to occur when the Hoxa-3 gene was “knocked out”? • the Hoxa-2 gene?
Anterior-Posterior Axis Formation • How has the application of retinoic acid provided us information about hox genes?
Anterior-Posterior Axis Formation • What is the connection between hox gene expression and the type of vertebrae formed?
Dorsal-Ventral Axis Formation • What is the connection between a-v pole and d-v axis?
Left-Right Axis • What appears to be responsible for specifying the left-right axis?