Chapter 11 - DEVELOPMENT OF CENTRAL NERVOUS SYSTEM Flashcards
Immature neurons which become the structural and functional cells of the central nervous system
Neuroblast
Develop into the connective tissue of the CNS called neuroglia.
Spongioblast
prosencephalon, mesencephalon, rhombencephalon
Primary brain vesicles
telencephalon, diencephalon, mesencephalon, metencephalon,
myelencephalon
Secondary Brain Vesicles
Ventral cranial flexure which occurs in the midbrain
Cephalic flexure
A gradual ventral bend between the hindbrain and the spinal cord
Cervical flexure
A slight dorsal bending in the rhombencephalon.
Inverted arrangement of white and gray matter is brought about by unequal growth of the basal
and alar regions of the brain vesicles.
Pontine flexure
from the posterior portion of the neural tube (where there is underlying notochord)
Spinal cord
covering of the CNS; composed of pia mater, arachnoid and dura mater; derived from neural crest cells
Meninges
gives rise to the nucleus pulposus, a gel-like substance surrounded by annulus fibrosus found between vertebrae
Notochord
spaces wherein CSF-secreting choroid plexuses are found
Ventricles
consists of cranial and spinal nerves
PERIPHERAL NERVOUS SYSTEM
sensory
afferent
motor
efferent
innervating skin and skeletal muscle
somatic
innervating vessels and viscera
visceral
Becomes the CNS
Neural tube
Some of it become pigment cells in skin, neurons, glial cells of PNS, forms mesenchyme.
Neural crest
Mesoderm blocks located just lateral to the notochord which induced ______ development
Somites
mesenchyme forms less-developed somites, called
somitomeres
(ventromedial region) gives rise to vertebrae, ribs, and endochondral bones at the
base of the skull.
Sclerotome
(lateral region) gives rise to the dermis of skin
Dermatome
(intermediate region) gives rise to skeletal muscles of the body
Myotome
True or false the most anterior part of the embryo is the oldest.
True
Folded endoderm encloses as a _________
blind hindgut
In the head region, dorso-ventral arches demarcated by grooves (clefts) appear these arches are called
Pharyngeal Arches
Pharybgeal Arches are bounded internally by
pharyngeal pouches
gives rise to bone and fascia
ectomesenchyme
true or false only the first three pharyngeal arches are externally evident in mammals
true
Telencephalon
cerebral cortex; rhinencephalon
lateral telocoeles
ventricles 1 and 2
openings of lateral
telocoeles
Foramina of Monroe
Diencephalon
Thalamus
Diocele
ventricles 1, 2 & 3
Epiphysis
pineal gland
Infundibulum
neurohypophysis of pituitary
gland
optic vesicle
retina of eye
Mesencephalon
corpora quadrigemina (superior and inferior colliculi)
Mesocoele
cerebral aqueduc
Metencephalon
cerebellum; pons
Myelencephalon
medulla oblongata
Myelocoele
ventricle 4
Neural canal
Spinal canal
Germinal layer of wall
Ependymal lining of spinal
cord
Mantle layer of wall
Gray matter/cortex
Marginal layer of wall
White matter/medulla
failure of cerebellum to develop due to destruction of cerebellar cortex. Generally caused by viral infections like feline panleukopenia in cat and
bovine virus diarrhea infection in calf.
Cerebellar hypoplasia and atrophy
premature degeneration of Purkinje cell layer of cerebellar cortex.
Cerebellar abiotrophy
accumulation of excessive amount of cerebrospinal fluid in the cranial
cavity
Hydrocephalus
thin walled and greatly enlarged lateral ventricle filled with CSF.
Hydranencephaly
general term for a malformation of the spinal cord
Myelodysplasia
reduced or absence of development of one or more segments of
spinal cord.
Hypoplasia (aplasia)
dilation of central canal due to excess accumulation of CSF
Hydromyelia
abnormal cavitation of the spinal cord
Syringomyelia
2 spinal cords develop beside each other usually in one set or meninges
and in one vertebral canal.
Diplomyelia
2 spinal cords develop with a partition between them. Usually in separate vertebral canals and have separate meninges
Diastematomyelia
cleft in the neural tube cause by failure of this part to close during neurulation.
Myeloschisis
protrusion of the meninges through an opening in the vertebral arches to form
a cyst beneath the skin.
Meningocoele
like menigocoele but both the meninges and the spinal cord protrude
Meningomyelocoele