Embryology I Flashcards
What does the metencephalon become?
- the brain stem
- pons
- cerebellum
- 4th ventricle
Where does neural cell proliferation occur?
in the ventricular zones (near the lumen of the neural tube)
In the telecephalon, the gray matter is located ____.
on the outside
The notocord will eventually develop into the _____.
nucleus pulposus
The neural progenitors of the spinal cord closest to the ventral aspect of the neural tube will develop into _____.
motor neurons
The _____ will eventually develop into the nucleus pulposus.
notocord
What is the cephalic flexure?
the bend btw the brain and brainstem/diecephalon and mesencephalon
How many segments does the prosencephalic vescicle form into?
3
The ____ plate becomes the afferent side of the spinal tract.
alar
A signal from the implanting trophoblast induces a “head organizer” that generates factor _____.
Cerebrus
Above the cephalic flexure, the dorsal direction is towards the top of the head, while below it, the dorsal direction is ______.
towards the back
How does sonic hedgehog (Shh) influence neurulation?
it induces the overlying ectoderm to divide, creating the neural plate
The caudal cell mass at day 28-32 ultimately gives rise to the ____ and ____.
- conus medullaris
- filum terminale
____ genes play a fundamental role in the AP patterning of nervous tissue.
Homeobox
Above the cephalic flexure, the dorsal direction is ______, while below it, the dorsal direction is towards the back.
towards the top of the head
What does the sulcus limitans do?
separates the ventral population from the dorsal population in the neural tube
How many rhombomeres are there?
8
From which embryological structure do the cerebral hemispheres and lateral ventricles all arise?
the telecephalon
In the forebrain, the neural tube will develop into what 3 discrete proliferative zones?
- cortex (dorsal)
- ganglionic eminences (medial and lateral)
- basal forebrain (ventral)
In the spinal cord, the gray matter is located ____.
on the inside
The _____ plate becomes the efferent side of the spinal tract.
basal
How many cell layers make up the cerebral cortex?
6
The basal plate becomes the ______ side of the spinal tract.
efferent
For patterning along the AP(RC) axis, the principal morphogens appear to be ____, ____, and _____.
- Wnts
- FGFs
- Retinoic Acid (RA)
Hox genes cause the development of _____.
the 8 rhombomeres
What axis does an entering sperm into an egg create?
the embryonic/abembryonic axis
___ genes cause the development of the 8 rhombomeres.
Hox
Hox gene expression varies according to position along the _____.
AP axis
Above the ______, the dorsal direction is towards the top of the head, while below it, the dorsal direction is towards the back.
cephalic flexure
The alar plate becomes the ______ side of the spinal tract.
afferent
The edge that leads implantation will become the ____ end of the embryo.
caudal
From which embryological structure do the the brain stem, pons, cerebellum, and 4th ventricle all arise?
the metencephalon
On what side of the blastocyst does implantation occur?
the ICM side
What does the myelencephalon become?
- the brain stem
- medulla oblongata
- 4th ventricle
What signaling molecule does the notocord release?
sonic hedgehog (Shh)
What does the mesecephalon become?
- the brain stem
- midbrain
- cerebral aqueduct
What does the dorsal population of neural tube cells become?
the alar plate
What is the first event that establishes symmetry in the mammalian egg?
sperm entry
The gray matter regions will become either the ____ plate or the _____ plate.
basal; alar
From which embryological structure do the brain stem, medulla oblongata, and 4th ventricle all arise?
the myelencephalon
The fiber pathway that splits the ganglionic eminence is the _____.
internal capsule
What causes dorsoventral patterning in the forebrain?
- morphogen gradients
- regional gene transcription changes
What does the ventral population of neural tube cells become?
the basal plate
From which embryological structure do the thalamus, hypothalamus, epithalamus, and third ventricle all arise?
the diencephalon
From which embryological structure do the brain stem, midbrain, and cerebral aqueduct all arise?
the mesecephalon
What are the components of the basal ganglia?
- putamen
- globus pallidus
- caudate nucleus
During cell migration in the telencephalon, each successive migration forms a more ______ layer of cells.
superficial
The neural progenitors of the spinal cord develop into distinct populations based on _____.
their position along the dorsal-ventral (DV) axis
Excess _____ causes an excess of posterior structures and is a powerful teratogen.
Retinoic Acid (RA)
What does the diencephalon become?
- the thalamus
- hypothalamus
- epithalamus
- third ventricle
What does the endoderm form?
the lining of the gut
How many segments does the mesencephalic vescicle form into?
none
What is the crease in the neural tube called?
the sulcus limitans
What is the sulcus limitans?
the crease in the neural tube
The cells making up the walls of the neural tube become ____ and ____ cells.
neurons; glial
How are the lateral ventricles connected?
they’re not- they connect to the 3rd ventricle
What does the telencephalon become?
- the cerebral hemispheres
- lateral ventricles
How many segments does the rhombencephalic vescicle form into?
2
