CNS/Eye/Ear Embryonic development Flashcards
Semicircular canals
The mesencephalon
The cerebral aquaduct of Sylvius
The diencephalon
Growth of the ramus of the mandible
What molecular signal is responsible for the differentiation of neuronal cells of the basal plate?
SHH
What molecular signal is responsible for differentation of nerons of the alar plate?
BMPs
Regions of brain
What generates CSF?
Choroid vesicles
Where does the third ventricle arise?
The diencephalon
In what fundmental way are cranial and spinal nerves similar?
Their motor neurons reside inside the central NS and sensory ganglia are outside
What cranial nerves originate from the hindbrain region?
IV - X
What induces the lens to form?
Contact between the optic vesicle and overlying ectoderm
What is the master gene for eye development?
PAX6
What is the master gene for the development of the optic nerve?
PAX2
Coloboma
When the choroid fissue fails to fully close
Typically caused by mutations in Pax2
When does laterality and midline signaling start during embryonic development?
The 3rd week
When in gestation would the insult that cause the following defect occur?
Third week (midline development)
Midline Eye fields are established early in the 3rd week with appearance of the anterior neural ridge in the neural plateSHH expression establishes the midline and separates the eye fields
What induces the otic placode?
Adjacent hindbrain region of the neural tube
Involve FGFs
What structure is the primitive tympanic cavity and auditory tube derived from?
The 1st pharyngeal pouch
What cell population gives rise to the malleus/incus/stapes?
Nueral crest cells
What structure(s) are the malleus/incus/stapes derived from?
Malleus/incus - first pharyngeal pouch
Stapes - second pharyngeal pouch
Which pharyngeal arche(s) are involved in forming the external ear?
The first and second
What structure gives rise to the malleus/incus?
Proximal Meckel’s cartilage of the first pharyngeal arch
Why does alcohol disrupt SHH signaling?
SHH has to be bound to cholesterol to effectively signal, alcohol dissolves cholesterol.
