Shared Flashcard Set

Details

Ethell
Neuroembryology
54
Medical
Graduate
03/02/2011

Additional Medical Flashcards

 


 

Cards

Term
Spinal chord goes down to approx what level?
Definition
L1
Term
Corpus Collusom
Definition
Connects the two halves of the cerebral cortex; large bundle of fibers
Term
80 degree angle
Definition
diencephalon and misencephalon sit at an eighty degree angle to the brain stem
Term
Name the ventricles
Definition
2 lateral ventricles, 3rd and fourth ventricle
Term
primary neurulation
Definition
begins in the middle of the embryo, proceeds rostrally and caudally at the same time, folding of the neural plate into tube and separation of tube from the ectoderm by a layer of neural crest cells that migrate into that position
Term
what happens if the Rostral neuropore doesn't close?
Definition
Anencephaly
Term
Craniorachischisis
Definition
Failure of rostral neural tube to close
Term
ALpha-fetal protein
Definition
will get into maternal blood supply if there is a neural tube defect
Term
Caudal NT closure defects
Definition
Spina Bifida; occulta (A) 1:10 frequency, failure of caudal vertebrae (sclerotome) to close but there is no neurological deformity; SB Cystica (B-C) has neurological complications
Term
myelomeningocele
Definition
Spina Bifida cystica; spinal chord is contained in an enlargement of the subarachnoid space and sticks out of child's back
Term
meningocele
Definition
spinal bifida cystica; spinal chord is continuous with ectoderm and does not stick out of the child's back, only the meninges stick out of the child's back
Term
Flashichieles
Definition
Term
Dorsal Ventral Polarity
Definition
floor plate (ventral) region of the neural tube gives rise to sonic hedge hog SHH which allows neural tissue to differentiate into motor neurons and interneurons, bone morphogenic proteins are in the dorsal part of the neural tube and allows differentiation of sensory neurons; determined by differential concentration gradients
Term
sensory modality
Definition
Alar Plate
Term
Motor modality
Definition
Basal Plate --> SHH
Term
inner ventricular zone
Definition
lines the central canal and becomes ependymal cells that line the ventricles and central canal
Term
mantle zone
Definition
middle layer for gray matter
Term
marginal zone
Definition
external most layer of neural tube that carries fibers and will form white matter
Term
Sulcus limitans
Definition
separates the alar and basal palte of the neural tube
Term
ependymal layer; ependymal cells
Definition
The ependymal cells line the walls of the ventricles and form the specialized choroid plexus epithelium which secretes the cerebrospinal fluid (CSF); often cuboidal with cilia
Term
Neural Crest cells comprise what part of the nervous system
Definition
cells at the meeting point between the neural folds that migrate away from the tube to become other structures; sensory ganglia, schwann cells, adrenal medulla, some cranial nerves, post-ganglionic neurons of the autonomic nervous system, satellite cells of the PNS, epidermal pigment cells.
Term
# primary vesicles
Definition
3; Prosencephalon, Mesencephalon, Rhombencephalon; end of 4th week rostral neurotube has closed and these vesicles are apparent
Term
cervical flexure
Definition
between the rhombencephalon and spinal chord and is not present in adult brain
Term
cephalic flexure
Definition
occurs at mesencephalic level and persist in adult brain and results in eight degree orientation of forebrain to brainstem
Term
Name what the five secondary vescicles become in the adult brain and their cavities
Definition
myelenchepalon --> medulla and caudal fourth ventricle
metencephalon --> pons and cerebellum and rostral fourth ventricle
mesencephalon --> midbrain cerebral aqueduct
diencephalon --> thalamus, hypothalamus, optic cup, etc. and thirs ventricle
Telencephalon --> cerebrum, corpus striatum and lateral ventricle
Term
3 parts to 5 parts
Definition
R --> metencephalon and myelencephalon
Mes stays Mes
Pros--> Telencephalon and diencephalon
Term
what happens as the pontine flexure forms?
Definition
the roof of neural tube thins and the alar plate moves laterally to the basal plate; lateral orientation of sensory to motor nerves maintained in caudal pons and rostral medulla brain; cranial nerves
Term
5 part brain: name flexure junctions and locations in sixth week
Definition
cervical flexure still there
cephalic flexure more pronounced
pontine flexure forming on dorsal surface of metencephalon -- future pons
Term
Pontine flexure
Definition
folds into a diamond shape and becomes the fourth ventricle, sensory neurons are lateral to the motor neurons
Term
Cerebellum originates from what?
Definition
the rostral edges of the pontine flexure gives rise to the cerebellum; lateral portions of alar plate in metencephalon form rhombic lips at 2nd month; enlarge during 3rd and 4th month, fusing at midline; cerebellum grows caudally over 4th ventricle, leaving just small portion of thin roof at caudal edge
Term
Telencephalon
Definition
dominates brain growth after 6 weeks; grows over almost all other structures in brain; neurons from subventricular zone migrate outwards thickening the outer edge and causing convultion; furture basal ganglia located in telencephalon adjacent to diencephalon becomes corpus striatum (most of basal ganglia)
Term
diencephalon
Definition
thalamus and hypothalamus, optic cup
Term
Insula
Definition
overlies diencephalon and telencephalon fusion
Term
Cerebral Cortex
Definition
Outer surface of telencephalon
Term
Rathkes pouch + diverticulum
Definition
diverticulum becomes the posterior (neurohypophysis) pituitary, floor of the third ventricle
Rathke's pouch (mouth) becomes adenohypophysis, anterior pituitary
Term
diencephalon becomes
Definition
thalamus (on top) hypothalamus (below, duh) and epithalamus (behind and I think he hints this is the pineal gland) third ventricle
Term
Telencephalon grows into which lobes
Definition
C shaped cerebral hemisphere, temporal and frontal lobes
Term
Lissencephaly
Definition
outer layer of cortex is smooth, there are no neurons there; defective neuron production or migration in 3-4 month
Term
new neurons are born next to the ependymal layer, what is the name of this zone?
Definition
subventricular zone
Term
Heteroptopias
Definition
randomly developed neurons from the subventricular zone displaced towards the ventricle creates bands of cell bodies and hyperexcitability; seizures
Term
Myelination
Definition
begins at the fourth month... proceeds postnatally and starts at the head and proceeds caudally and correlates with the ability of developing infant to control movements;myelination of corticospinal tract occurs from birth to two years (motor control)
Term
Fetal Alcohol syndrome
Definition
the corpus collsum that connects the two hemispheres is missing
Term
Fetal Alcohol syndrome
Definition
the corpus collsum that connects the two hemispheres is missing
Term
Hydrocephalus
Definition
congenital abnormality in cerebral aqueduct, too skinny, fluid continues to be produced in lateral ventricles and head swells
Term
secondary neurulation
Definition
rostral end of the neural tube closes at day 23 and the caudal end of the neuro tube closes at day 25
Term
Arnold-chiari malformations
Definition
a type of spina bifida, or rachischisis, in which the caudal end of the spinal chord is tethered to the skin around the sacrum; can cause traction injuries to brain stem and cerebellum; 1:1000 frequency; can lead to stenosis of ventricles
Term
sulcus limitans
Definition
a longitudinal groove in the neural tube wall of the embryo; stretches from the mesencephalon caudad; also separates the alar plate and dorsal plate of the neural tube
Term
subventricular zone
Definition
superficial to ventricular zone; where proliferating neurons are born; in spinal chord cell bodies are on inside and fibers, white matter, stays on outside; in the cerebral cortex proliferating neurons migrate to to the outside and fibers are found deep to them
Term
placodes
Definition
clusters of neural crest like cells that form the following structures; lens of the eye, inner ear hair cells, olfactory epithelium, ganglia of cranial nerves 5, 7, 8, 9, 10. these placodes are induced to differentiate by underlying neural structures ro neural tube
Term
somites
Definition
lateral to neural tube 1) sclerotomes--> vertebrae 2)myotome--> muscle 3) dermatome --> skin
Term
Lamina terminalis
Definition
connects the two lobes of the telencephalon and provides a framework for the crossing of cortical fibers to form the corpus callosum and anterior commissure (fiber tracts that connect two hemispheres)
Term
rathke's pouch
Definition
in growth in the roof of primitive mouth that fuses with a diverticulum of the third ventricle, which becomes neurohypophysis and is continuous with hypothalamus; original connection withprimitive mouth is lost; adenohypophysis develops from the mouth
Term
C shape growth of cortex
Definition
frontal lobe first grows forward and the temporal lobe grows posteriorly and then anteriorly. C shape growth
Term
which months in brain development have tremendous growth
Definition
2nd and 3rd months
Supporting users have an ad free experience!