anatomy nervous system development

ectoderm

the CNS develops from which embryonic layer?

1. neural plate is formed by the ectoderm

2. neural plate fold, forming the notochord

3. neural plates elevate

4. final folding of the neural plates form a neural tube, which forms the CNS

5. cells excluded from the tube are called neural crests, which later form the PNS

describe the steps of CNS formation demonstrated in this image.

neural tube

what is the structure formed by the folding of the neural plate that becomes the CNS?

the neural tube

what is this structure?

neural tube

which part becomes the CNS?

neural crest

which part becomes the PNS?

a cavity in the neural tube filled with fluid. it always remains

what is the sulcus limitans?

3 vesicles that later become 5 vesicles (later forming the brain); the spinal cord

the cranial end of the neural tube forms __________, while the caudal end of the neural tube forms _________

forebrain, midbrain, hindbrain

1. Telencephalon

2. Diencephalon

3. Mesencephalon

4. Metencephalon

5. Myelencephalon

as the cranial end of the neural tube develops, it forms 3 main vesicles, called the ________, ___________, and _________. then, they further develop into 5 vesicles. what are they called?

the cerebrum

what does the telencephalon become?

telencephalon

which vesicle becomes the cerebrum?

the thalamus and hypothalamus

what does the diencephalon become?

the diencephalon

which vesicle becomes the thalamus and hypothalamus after birth?

mesencephalon

which vesicle becomes the midbrain?

midbrain

the mesencephalon becomes the.....

myelencephalon

which vesicle develops into the medulla oblongata?

medulla oblongata

what does the myelencephalon become?

metencephalon

the pons and cerebellum arise from which embryonic vesicle?

pons and cerebellum

the metencephalon becomes the _____ after birth

2 lateral ventricles in the cerebrum

third ventricle in the diencephalon (thalamus/hypothalamus)

cerebral aqueduct in the midbrain

fourth ventricle in the brain stem

where do the neural canals exist in the adult brain?

diencephalon (thalamus and hypothalamus)

where is the third ventricle located?

brain stem

where is the fourth ventricle located?

in the midbrain

where is the cerebral aqueduct located?

the most cranial part of the brain

where is the olfactory bulb?

cerebrum

what is 1?

thalamus

what is 2?

2

where is the thalamus?

hypothalamus

what is 3?

3

where is the hypothalamus?

cerebellum

what is 4?

midbrain

what is 5?

brain stem

what is 6?

PNS:

sensitive ganglia

sympathetic ganglia

parasympathelic ganglia

schwann cells

the neural crests become..

membranes that protect the brain and spinal cord

what are the meninges?

dura mater

the outer meninges is the ______

subarachnoid space

the cavity in between the arachnoid and pia mater is called the _______

dura mater

arachnoid

pia mater

what are the meninges layers, from external to internal?

a congenital disorder where the CSF content in the brain ventricles increase (due to either increased CSF production or a blockage in the draining system). leads to increased pressure on brain tissue

what is hydrocephalus?

brachiocephalic breeds

what breeds are more prone to hydrocephalus?

hydrocephalus

what congenital disorder does this puppy have?

hydrocephalus

what congenital disorder does this cow have?

hydrocephalus

which congenital disorder is characterized by an increased CSF content in the brain ventricles, leading to pressure on the nervous tissue?

cerebral hypoplasia

what is the medical term for the congenital disorder causing poor brain development?

the congenital disorder of no brain develpment

what is cerebral aplasia?

the congenital disorder where the skull does not close completely, so part of the brain is exposed

what is cranioschisis?

a congenital disorder where there is an abnormal sac of fluid, brain tissue, and meninges extending through a defect in the skull

a meningoencephalocele is....

cerebellar hypoplasia

what is the name for poor development of the cerebellum?

1 or more vertebrae do not form their arch normally during development, so the spinal cord is exposed and more susceptible to injury

what is spina bifida?

spina bifida

what congenital disorder does this baby have?

severe forms of spina bifida where the entire spinal vertebrae are not closed due to failure of the neural tube to close, leaving the entire spinal cord exposed

what is rachischisis/myeloschisis?

spina bifida (rachischisis and myeloschisis are severe forms)

what is the congenital disorder where vertebrae do not close correctly, leaving the spinal cord exposed?

the development of a cyst/cavity within the spinal cord

what is syringomyelia?

english bulldogs

spina bifida is common in what breed of dog?

king charles spaniels

syringomyelia is a common congenital disorder in what breed?

a dilation of the central canal of the spinal cord by CSF

what is hydromyelia?

syringomyelia

what is the congenital disorder where there is a formation of a cyst/cavity within the spinal cord?