What are the archenteron and the blastopore? What is the stage of the embryonic development in which these structures are formed? What are the destinations of the archenteron and of the blastopore?
5After the neurula stage and from its ventral portion to the dorsal how can the morphology of the embryo be described?
5What is gastrulation? How during gastrulation are the first two germ layers formed? Which are these germ layers?
5Which is the extra embryonic membrane whose function is to store nitrogen wastes of the embryo? Is this function present in placental mammalian embryos?
5What is the chorioallantois membrane present in the embryonic development of reptiles and birds? How does this membrane participate in the energetic metabolism of the embryo?
5How does the embryo turn from gastrula into neurula? How is the neural tube formed? What is the embryonic origin of the nervous system in vertebrates?
5
What are other organs and tissues made from that germ layer?
How is the yolk sac formed?
Explain archenteron?
What stage follows gastrulation?
Explain the difference between amnion and chorion?
Explain notochord?
In which type of animals does the placenta exist? What is its main function?
What is gastrulation? How during gastrulation are the &rst two germ layers formed? Which are these germ layers?
Explain foetal pole?
What is the cell division during the first stage of the embryonic development called? How is this stage characterized?
What are histogenesis?
What is the main function of placenta?
Define polyembryony?
What are the blastopore?
What is the function of the umbilical cord?
