Animal Developmental Biology Past Paper PDF 2024

Introduction A framework for understanding animal development BIO412/712 Animal Developmental Biology 13/ 08/ 2024 Class 2  Same embryo over time? Or Embyos of different species? Embyonic resemblances argue for genetic connectedness of anima...

Introduction A framework for understanding animal development BIO412/712 Animal Developmental Biology 13/ 08/ 2024 Class 2  Same embryo over time? Or Embyos of different species? Embyonic resemblances argue for genetic connectedness of animal groups - Darwin Phylotypic stage: Pharyngula - vertebrate -chordate Tunicates - sea squirts Vertebrates Evolutionary embryology Tunicates - sea squirts are related to vertebrates - Alexander Kowalevsky 19th century Tunicates - sea squirts: sister group to vertebrates Notochord Pharyngeal arches Darwin: Community of embryonic structures reveals community of descent  Karl Ernst von Baer, 19th century Principles of von Baer General features of a larger group appear earlier in development than the specialised features of a smaller group Less general characters develop from the more general, until finally the most specialised Descent with modification Common descent Modifications  Forelimb homology Descent with modification Developmental change leads to evolutionary change Weatherbee et al, 2006 Homology vs. Analogy Mutations in genes controlling developmental processes can generate a selectable variation  Descriptive embryology —> Experimental embryology Fate map Map larval/adult tissues onto specific parts of embryos How does a fate map help? All images from Gilbert, Baressi 11th Edition, Sinauer Fate mapping with vital dyes Vital dyes dilute when cells divide Short duration trace Quail-chick chimeras for fate mapping N Le Douarin Genetic labelling and tracing the descendants Neural crest cells Foregut Graft transgene reporter +ve donor into reporter –ve recipient Introduce fluorescent reporter using virus Microinjection of DNA / RNA of fluorescent or enzyme reporter  For further reading on cleavage pattern Vertebrate Embryonic Cleavage Pattern Determination Andrew Hasley, Shawn Chavez, Michael Danilchik, Martin Wühr, and Francisco Pelegri Adv Exp Med Biol. 2017; 953: 117–171. doi: 10.1007/978-3-319-46095-6_4