Intro To Developmental Biology Flashcards
During cleavage divisions, does the cell grow in size?
No
What 2 components make up the blastocyst?
The trophoblast and the inner cell mass
What 2 components does the inner cell mass divide into?
The epiblast and the hypoblast
What does the epiblast form?
The embryo proper (ectoderm, mesoderm and endoderm) and the amniotic membrane
What does the hypoblast form?
Heuser’s membrane (primary yolk sac)
What does the trophoblast form?
The chorion
Where are the embryonic stem cells derived from?
The inner cell mass
What are the 4 main derivatives of the mesoderm?
Notochord, somite, intermediate mesoderm, lateral plate mesoderm
What happens to the epiblast cells during gastrulation?
They migrate to, and pass through, the primitive streak and node (ingression)
What signals the ectoderm to form the neural plate?
The notochord
When does the neural tube close?
Begins end of week 3, complete by end of week 4
When does the embryonic disk start to fold?
Week 4
Define neural crest cells
Migratory cells from the dorsal neural tube
When are somites formed?
Day 20-30
What tissues are formed by somites?
Dermatome, myotome and sclerotome
What does the dermatome give rise to?
Dermal layer of skin
What does the myotome give rise to?
Skeletal muscle
What does the sclerotome give rise to?
Cartilage and bone of the occipital bone and axial skeleton
What are the 5 neural tube regions?
Telencephalon, diencephalon, mesencephalon, rhombencephalon, spinal cord
What does the intermediate mesoderm give rise to?
Reproductive system (excluding germ cells) and kidneys
What are the 2 components of the lateral plate mesoderm?
Somatic layer (outer) and splanchnic layer (inner)
What does the splanchnic layer of lateral mesoderm give rise to?
Blood, heart, blood vessels, muscles of gut
What does the somatic layer of lateral plate mesoderm give rise to?
Limb skeleton and connective tissue
What is the coelum and what does it give rise to?
Space between the somatic and splanchnic layers. It gives use to the pleural, pericardial and peritoneal cavities
What are the 4 main vertebrate model organisms?
Mouse, chick, frog, zebrafish
Which gene is responsible for eye formation?
Pax6
What 2 cell types can stem cells give rise to?
Progenitor cells, more stem cells
What is an example of epithelial to mesenchymal transition?
Neural crest
What is an example of mesenchymal to epithelial transition?
Formation of gut tube from migratory epithelium
Which 3 regions interact to generate cell behaviours and differentiation?
Cell surface receptors, cytoplasm and nucleus
Which signalling pathway is involved in FGF and VEGF signalling?
Receptor tyrosine kinase
Binding of BMP to a receptor triggers phosphorylation o which protein?
SMADs
What happens to the patched and smoothened receptors when sonic hedgehog is present?
Shh binds to patched which stabilises smoothened
What happens to the patched and smoothened receptors when shh is not present?
They are internalised and the Gli activators are degraded. Gli target genes are switched off.
Which receptor does wnt bind to?
Frizzeled
The binding of which ligands triggers notch signalling?
Delta and jagged
