The origins and birth of neurons 1 Flashcards
What is neural induction?
producing a region of the body where the neurons are formed
What is gastrulation?
The early embryo undergoes morphogenetic movements, generating the germ layers
What is the outer germ layer?
Ectoderm
What is underneath the ectoderm?
The mesoderm
What is under the mesoderm?
The endoderm
Where is the nervous system always formed from (ecto, meso, endo)?
Ectoderm
What is the central part of the ectoderm?
The neural plate
What is a fate map?
diagram of an egg or blastula, indicating the fate of each cell or region at a later stage of development
Which stage is just before gastrulation?
Blastula
What are the two poles of the blastula?
Animal and vegetal
Which pole is the darker side?
Animal pole
First sign of gastrulation?
Cells “tucking in”
How is the dorsal side defined?
It is where the cells “tuck in” at the start of gastrulation
What is the opposite of the dorsal side?
Ventral side
What are the two axis on an embryo in gastrulation?
Animal vegetal, and dorsal ventral
Which cells “tuck in” at the start of gastrulation?
The cells that will form the mesoderm
When can a fate map be done?
Any time during early development (after first cell stage)
Where are the cells (axis wise) that end up forming the nervous system?
The animo-dorsal region
What main structures does the ectoderm give rise to?
The epidermis (skin outer layer) and the nervous system
How is fate mapping done?
Label cells early on in the embryo and then look later on at where in the developed embryo these marks are
What is the dorsal blastopore lip?
First set of cells that tuck in
What happens when a dorsal blastopore lip from one embryo is transplanted to the ventral side of another embryo?
The recipient embryo develops a second body axis
What is the default state of ectodermal cells?
Neural
Why does the whole ectoderm not become neural?
It is exposed to a BMP4 signal
