CNS Development And Brain Subdivisions Flashcards
When does the formation of the nervous system occur?
During the embryonic stage (end of second week to end of eigth week).
What must occur in order for simple cuboidal epithelium to become a neural plate?
The simple cuboidal epithelium must become simple columnar epithelium.
When the neural plate folds along the anterior-posterior axis to form the neural groove, what are also formed?
Neural folds
Neural folds cannot form unless what happens to the epithelium?
The epithelium must become columnarized.
The folding process of the neural tube occurs along what regions?
Cranial and caudal regions.
What do opposing edges of neural folds form, what what does it separate from?
They form the neural tube, which separates from the simple cuboidal ectoderm.
What neuropore closes first?
Superior neuropore (Day 27)
What are the regions of the tripartite brain?
Prosencephalon
Mesencephalon
Rhombencephalon
The prosencephalon gives rise to what two divisions of the pentapartite brain?
Telencephalon
Diencephalon
The mesencephalon gives rise to what region of the pentapartite brain?
Mesencephalon;
It is the relay center for information in the brain.
The rhombencephalon gives rise to what regions of the pentapartite brain?
Metencephalon
Myencephalon
You are conducting an experiment on olfactory reflexes and emotional responses to odors in the diecephalon. What structures should you study?
Hypothalamus (suparaoptic and paraventricular nuclei).
What region of the brain controls and integrates ANS?
Diencephalon
What is a function of the diencephalon:
A. Intermediary between nervous and endocrine systems
B. Controls normal body temperature
C. Maintains extracellular fluid volume
D. Biorhythm oscillator
All of the above
What is the disorder that occurs when the cranial end of the neural tube fails to close?
Anencephaly
You encounter a still-born fetus who has a single orbit, as well a a nose above the orbit. When conducting an autopsy, what will be of significance in the prosencephalon?
It will have failed to divide into two cerebral hemispheres.
This is known as holoprosencephaly.
Spina bifida is the result of what?
A failure of the inferior neuropore to close.
It occurs in CAUDAL regions.
You encounter a patient who has spina bifida, but you are not sure what type of spina bifida they have. You note that they do not have vertebral arches in caudal areas, but spinal cord function is normal. What type of spina bifida does the patient most likely have?
Spina bifida occulta
You are performing an ultrasound on a patient and note that the fetus has a sac-like cyst at the end of the spine. What type of spina bifida does the fetus most likely have?
Spina bifida cystica
You encounter a patient who has spina bifida cystica. Upon examination of the sac at the caudal region of the spinal cord, you note that meninges are only found in the sac. What type of spina bifida cystica does the patient most likely have?
Meningocele
You encounter a patient with spina bifida cystica. You note that meninges and spinal cord are found in a sac in the caudal region of the spinal cord. The patient also has lower extremity paralysis. What type of spina bifida cystica does the patient most likely have?
Meningomyelocele
What is the most severe of the spina bifida cystica disorders?
Myeloschisis
It is the failure of the caudal neural folds to close.
What are some characteristisc of Arnold-Chiari Deformity?
Inferior cerebellum and medulla are elongated and protrude into vertebral canal.
Meduall and pons are small and deformed.
Hydrocephalus
Malformation of lower cranial nerves.
You encounter a patient who has hydrocephalis, deafness, tongue, facial muscle and lateral eye movement weakness. An MRI scan shows that the patient has a small, deformed medulla and pons, and the medulla protrudes into the vertebral canal. What disorder does the patient most likely have?
Arnold-Chiari Deformity
