Embryonic development Flashcards
What is ectoderm?
the outer layer (skin and nervous system)
What is mesoderm?
the middle layer (axial skeleton, muscles and connective tissue)
What is endoderm?
the inner layer (gastrointestinal, respiratory and urinary system)
What is the gastrulation?
the process when the cell goes from one layer to multiple layers
What layers do you find in the endoderm?
Digestive system, liver, pancreas, inner layer of the lungs
what are the layers of mesoderm?
circulatory system, lungs (epithelial layers), skeletal system, muscular system
what are the layers of ectoderm?
hair, nails, skin, nervous system
What’s a notochord?
a distinct cylinder of mesodermal cells that extends along the midline of the embryo from mid-anterior to posterior (define the symmetry for the entire embryo)
What is the ectoderm called that lies immediately abow the notochord and what’s it’s function?
It’s called neuroectoderm and it gives rise to the entire nervous system
What is neurulation?
it’s the process that follows gastrulation in which the neural tube is formed
How does the neurulation begin?
It begins with the thickening of the neuroectoderm under the influence of the notochord to form the neural plate
How is the neural groove formed?
The neural plate invaginate and form the neural groove. The lateral margins of the neural plate fold inwards forcing a further invagination of the neural groove
How is the neural tube formed?
Both sides of the neural plate fuse to form the neural tube
What forms the neural crease?
The margin cells from the neural plate are not recruited the the neural tube and form the neural crease. The cells forms two wings placed between the neural tube and the surface ectoderm.
Whats the precursor of the central nervous system? (brain and spinal cord)
The neural tube
