Development of the Brain Flashcards
During week 3 the development of the neural plate, comprised of the neural folds found laterally, and the neural groove found medially, is induced by what structure?
Notochord
The neural tube forms at which of the following somites?
A. 1st
B. 2nd
C. 3rd
D. 4th
E. 5th
5th Somite
Neuralation begins at the 4th week, and grows both cranially (rostrally) and caudally. These cranial and caudal neuropores eventually close off, but at different times. What day does the cranial and caudal neuropore close?
Cranial Neuropore: Day 25
Caudal Neuropore: Day 27
The 4th pair of somites and the superior somites, or the cranial 2/3rds of the neural tube forms what structure?
The caudal 1/3 of the neural tube forms what structure?
Cranial 2/3rds= Brain
Caudal 1/3: Spinal cord
The fusion of the neural folds causes the rostral/cranial neropore to close and form the primary brain vesicles.
What are the 3 primary vesicles?
Prosencephalon
Mesencephalon
Rhomboencephalon
During week 5 the 3 primary brain vesicles give become 5 secondary vesicles. What are these 5 secondary vesicles, and which primary vesicles do they come from?
Prosencephalon: Telencephalon and Diencephalon
Mesencephalon
Rhombencephalon: Metencephalon and Myelencephalon
What do the walls of the Telencephalon become?
What do the cavities of the Telencephalon become?
Cerebral Hemisphere
Lateral Ventricles and part of 3rd ventricles
What do the walls of the Diencephalon become (3)?
What do the cavities of the Diencephalon become?
Epithalamus, Thalamus, Hypothalamus
3rd Ventricle
What do the walls of the Mesencephalonbecome?
What do the cavities of the Mesencephalon become?
Midbrain
Cerebral aqueduct
What do the walls of the Metencephalon become?
What do the cavities of the Metencephalon become ?
Pons and Cerebellum
Upper part of 4th Ventricle
What do the walls of the Meyelencephalon become?
What do the cavities of the Meyelencephalon become?
Medulla Oblongata
Lower part of the 4th Ventricle
During week 5, the brain bends and grows rapidly producing the flexures of the brain. All of the following flexures create a fold on the anterior portion, except for which of the following that forms on the posterior portion and is ultimately responsible for putting the cerebellum over and posterior to the pons?
A. Midbrain Flexure
B. Cervical Flexure
C. Pontine Flexure
Pontine Flexure
Metencephalon and meyelencephalon junction
Brain flexures produce a considereable amount of variation thats seen in the postiioning of gray and white matter. Indicate where each of the following flexures are found?
Midbrain Flexure:
Cervical Flexure:
Pontine Flexure:
Midbrain Flexure: at the mesencephalon
Cervical Flexure: between the hindbrain and spinal cord
Pontine Flexure: at metencephalon and myelencephalon junction
The Cavity of the hindbrain is responsible for forming what two structures?
Fourth Ventricle
Central Canal in the medulla
The alar plates are located more laterally and give rise to __________, while the basal plates are located more medially and gives rise to __________
Alar plates: AFFERENT inputs
Basal Plates: EFFERENT outputs
Neuroblasts in the alar plates found in the caudal portion of the meylencephalon go into the marginzal zone and become what two sensory nuclei?
Gracile Nucleus
Cuneate Nucleus
The rostral portion of the myelencephalon is wide and flat due to the movement of what flexure?
What structure does the roof plate of the myelencephalon’s cavity give rise to?
Pontine Flexure
inferior portion of the 4th ventricle
The metencephalon forms the pons and the cerebellum, as well as the superior portion of the 4th ventricle. Which of these develops from the dorsal part of the alar plates?
Cerebellum
What flexure is responsible for forcing the walls of the pons laterally in the metencephalon?
Pontine Flexure